NOTE: The methods described here are those used at UCLA for performing FLA of the prostate. The research project, including the protocol, were approved by the UCLA institutional review board (IRB). All patients have had targeted biopsy of the prostate, in which the MRI has been interpreted by an experienced uro-radiologist. Lesions visible on MRI were biopsied within the region of interest (ROI) and outside the ROI using a systematic template. The positive biopsies and MRI region of interest are used to plan treatment with laser ablation in order to treat the index lesion and create a margin of treated tissue around the tumor, given that MRI underestimates the size of the tumor.21 Only patients with intermediate risk prostate cancer (GG2-3 PSA &#60; 20, Stage &#60; T2), a single index ROI and no contralateral clinically significant prostate cancer are considered eligible for treatment. Patients with bleeding diathesis or inability to tolerate treatment without sedation are considered ineligible.
1. Treatment Planning
<ol>
	<li>Prior to treatment, plan ablations targets using input from the MRI and biopsy coordinates.</li>
	<li>Perform treatment planning with the provided software.</li>
</ol>
2. Procedural Room Preparation
<ol>
	<li>Display a laser warning sign outside of the procedure room.</li>
	<li>Position the workstation for comfortable access.</li>
	<li>Power on the workstation, fusion device and transrectal ultrasound.</li>
	<li>Enter login credential and select the desired patient from the default work list containing unexecuted plans. 
	&#8203;NOTE: New treatment plans can be added via a USB or internet connection as detailed in the user manual.</li>
	<li>Hang a bag of saline from the designated hook on the workstation; a waste saline return bag is also attached.</li>
	<li>Prime the saline tubing by allowing gravity flow of fluid prior to locking the tubing. The saline is then connected to the peristaltic pump and hung for later use during the procedure.</li>
</ol>
3. TRUS probe preparation
<ol>
	<li>Apply ultrasound jelly directly to a clean TRUS probe. 
	NOTE: At UCLA, all TRUS probes are disinfected via an automated system with vaporized hydrogen peroxide solution.</li>
	<li>Fit a condom over the ultrasound jelly onto the TRUS probe and secure it at the base using a rubber band. 
	NOTE: Per standard practice attempt to remove air bubbles trapped under the condom.</li>
	<li>Place a multi-channel guide over the condom and lock it in place using the metal clamp. A second condom with internal ultrasound jelly can be placed over the multi-channel guide to augment patient comfort.</li>
</ol>
4. Patient preparation
<ol>
	<li>Direct the patient to cleanse their rectal vault with and enema on the morning of the biopsy.</li>
	<li>Ensure that the patient has obtained prophylactic antibiotics 60 minutes prior to the procedure22. 
	NOTE: At UCLA, 1 g of Ertapenem is administered intramuscularly 60 minutes prior to the procedure. This decision was made based on the UCLA antibiogram and had prevented post-biopsy septic episodes over the last 1500 transrectal biopsies.23 Given this success, we elected to also use it for transrectal laser ablation.</li>
	<li>Provide patients with Acetaminophen 1000 mg PO, Ketorolac 30 mg IM, and optionally but recommended Diazepam 10 mg PO, 60 minutes prior to the procedure. 
	NOTE: Patients may experience a moderate desire to void or pressure in the penis during the procedure. In our experience, no narcotics are beneficial.</li>
	<li>Patients may find it useful to bring personal music and headphones as an additional anxiolytic.</li>
	<li>Place the patient in the left lateral decubitus position as for transrectal biopsy.</li>
	<li>Record patient vital signs prior to beginning the procedure and at 30-minute intervals.</li>
</ol>
5. Administration of prostatic nerve block
<ol>
	<li>Insert the lubricated TRUS probe until the center of the prostate is clearly visible.</li>
	<li>Optimize the ultrasound gain, time gain compensation (TGC sliders on the right of most ultrasounds), depth and focus so that the prostate is centered within the ultrasound viewing monitor. 
	NOTE: The optimal gain results in a medium-gray image within the peripheral zone. The TGC sliders are best set at a gradually sloping angle to compensate for wave attenuation of distant tissues. The ultrasound depth and focus will depend on prostate size. The focus should be set to the peripheral zone to optimize visualization of acoustic markers on the laser catheter.</li>
	<li>Activate the on-screen biopsy guide and place a 22 gauge spinal needle through the center of the multichannel guide to anesthetize the prostate. 
	&#8203;NOTE: At UCLA we anesthetize the prostate in the sagittal plane by placing 10-20 mL of Lidocaine/Marcaine at the junction of the prostate and seminal vesicles. Correct infiltration will cause a separation of the seminal vesicles and prostate from the rectal wall.</li>
</ol>
6. MRI-US fusion
<ol>
	<li>Position the imaging fusion system and workstation close enough to the patient in order to visualize the workstation screens while also observing the patient.</li>
	<li>If using the Artemis, use a technique for docking and image registration previously described.24</li>
</ol>
7. Target acquisition
<ol>
	<li>Navigate the ultrasound to the center of the first ablation site using digital targets supplied by the fusion device. This process is similar to guiding the ultrasound to a MRI region of interest during fusion biopsy. 
	NOTE: Each ablation site is determined from the MRI region of interest and positive biopsy cores (Figure 1). The patient&#39;s treatment plan should be transferred to the workstation and fusion device during procedure room preparation described above.</li>
	<li>Select the current ablation zone.</li>
</ol>
8. Placement of laser catheter and temperature probe
<ol>
	<li>Place the 14-gauge laser catheter into the center chamber of the multichannel guide. 
	NOTE: The multichannel guide is curved to provide slight friction thus preventing treatment elements from slipping backwards during ablation. Overcome this friction by rotating back and forth while advancing the laser catheter into the prostate.</li>
	<li>Advance the laser catheter until four echogenic bands are visualized and aligned with the on-screen depth marker. For a peripheral zone ablation, the markers will be several mm outside the prostate capsule (Figure 2). 
	NOTE: In the case of a fibrous posterior capsule, the laser catheter may deflect rather than traversing the prostate capsule. Any deflection will be visible on the ultrasound during the insertion. Should deflection occur, remove the laser catheter and insert a leader, such as the sturdy thermal probe, to create a pilot opening in the capsule. The laser catheter can then be advanced as planned.</li>
	<li>Insert the thermal probe to the left or right of the laser catheter depending on the treatment plan. At the correct depth, the thermal probe interlocks with the laser catheter handle, allowing it align in the correct orientation. 
	NOTE: After placement, check that the slot on the thermal probe seated into the handle of the laser catheter. The thermal probe will magnetically lock in place and prevent rotation during treatment.</li>
	<li>Connect primed intravenous tubing from the saline bag to the proximal inflow port on the laser catheter.</li>
	<li>Connect the returning saline from the distal outflow port to a clear drainage bag so that returning fluid can be visualized. 
	&#8203;NOTE: Circulating saline around the laser catheter will cool the fiber during treatment</li>
</ol>
9. Perform the Safety Checklist
<ol>
	<li>While on the treatment monitoring screen, select the desired ablation site. Once the appropriate ablation is selected, press &#39;CONFIRM SELECTION.&#39; A safety checklist will now occupy the left side of the workstation monitor. 
	NOTE: This step will begin circulating saline through the laser catheter. Small bubbles introduced when connecting the intravenous tubes are initially visible on ultrasound around the laser. This can act as an additional check for the laser catheter position.</li>
	<li>Follow the safety checklist, ticking off the boxes once complete.</li>
	<li>Ensure that all individuals in the room don laser safety goggles including the patient.</li>
	<li>The workstation computer system will automatically check the thermal probe to ensure that all thermocouples are reading uniform body temperatures between 30 - 40 &#176;C.</li>
	<li>Confirm that the laser catheters&#39; four echogenic bands are located at the prostate capsule, as placement of the thermal probe may push the prostate away from the laser catheter. 
	&#8203;NOTE: The ablation zone begins 5 mm distal to the echogenic markers and extends another 27 mm in length and 18 mm in diameter (maximal).</li>
</ol>
10. Performing the Laser Tissue Ablation
<ol>
	<li>Once the safety checklist is complete press &#39;START LASER&#39; to begin the ablation.</li>
	<li>Monitor treatment progress in real-time using temperature readings, timer, and damage map. 
	NOTE: Evaluate tissue temperature utilizing the multi-line graph to the left of the prostate model. The rectal temperature is marked in white and should not exceed 42&#160;&#176;C. Temperature at the tip of the laser catheter is marked in blue (Figure 3). The laser will automatically shut off if the laser tip exceeds 75&#160;&#176;C or the rectal wall exceeds 42&#176;C. 
	NOTE: Once the laser is active, monitor treatment time at each ablation site using the red bar at the top of the screen. A damage map gives a 3D representation of treated tissue based on temperature and time. 
	NOTE: Note changes on B-mode ultrasound. Prostate tissue usually does not change in appearance during laser ablation. With serial treatments the tissue may take on a hypoechoic appearance, but US visualization primarily serves for positioning of the laser. 
	NOTE: Monitor for concerning ultrasound features as follows:
	<ol>
		<li>Swirling micro bubbles forming beyond the echogenic laser catheter bands may indicate a leak in circulating saline due to super-heating. While this has no safety impact, treatment progress may be slowed.</li>
		<li>An increase in hyperechoic nature or &#39;whitening&#39; of the rectal fat may occur if the laser catheter is inadvertently pulled back, causing heating of the perirectal fat.</li>
		<li>If either of these ultrasound findings are observed laser treatment should be stopped.</li>
	</ol>
	</li>
	<li>The laser automatically stops once the timer runs out, but a practitioner can elect to end the ablation manually by pressing &#39;STOP THE LASER.&#39; Saline will continue to flow, cooling the laser tip. 
	NOTE: Consider stopping the ablation early if temperatures plateau above 55 &#176;C for greater than 60 seconds.</li>
	<li>Keep the laser catheter and thermal probe in place until the temperature of the laser catheter has dropped below 42&#160;&#176;C, thus preventing rectal wall heating during withdrawal of the laser catheter.</li>
</ol>
11. Subsequent ablations
<ol>
	<li>Position the ultrasound at the next ablation site using the digital targets supplied by the fusion device.</li>
	<li>Assess whether the live ultrasound images remain registered to the prostate MRI, and perform a motion compensation if needed. 
	&#8203;NOTE: If using the Artemis, the technique for motion compensation is described in the previously referenced video.24</li>
	<li>On the treatment monitoring screen, the initial ablation site will now be greyed out; however it can be treated again if deemed necessary.</li>
	<li>Select the next ablation site from the left side of the screen and repeat the process described in steps 8 - 10.</li>
</ol>
12. Conclude Treatment Session
<ol>
	<li>Once all ablation sites have been treated, a &#39;FINISH TREATMENT&#39; button will appear. Pressing this button will display a treatment review screen that displays quantitative metrics for the treatment session.</li>
	<li>Remove the TRUS probe from the patient&#39;s rectum. Manual pressure may be applied to the rectal wall overlying the prostate to facilitate hemostasis.</li>
</ol>

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Use of Laser Interstitial Thermal Therapy in the Focal Treatment of Localized Prostate Cancer - NCT02224911 Available from: <a target="_blank" href="https://clinicaltrials.gov/ct2/show/NCT02224911">https://clinicaltrials.gov/ct2/show/NCT02224911</a> (2020)</li><li>. Focal Laser Ablation of Prostate Tissue - NCT02357121 Available from: <a target="_blank" href="https://clinicaltrials.gov/ct2/show/NCT02357121">https://clinicaltrials.gov/ct2/show/NCT02357121</a> (2020)</li><li>. Focal Laser Ablation of Prostate Cancer -NCT04305925 Available from: <a target="_blank" href="https://clinicaltrials.gov/ct2/show/NCT04305925">https://clinicaltrials.gov/ct2/show/NCT04305925</a> (2020)</li><li>McNICHOLAS, T. A., STEGER, A. C., BOWN, S. 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Transrectally delivered, outpatient MRI-guided laser focal therapy of prostate cancer: 9.5 year interim results of NCT #02243033, Presentation at the AdMeTech 4th Global Summit on Precision Diagnosis and Treatment of Prostate Cancer Available from: <a target="_blank" href="https://www.admetech.org/wp-content/uploads/2019/08/DMI-FOCAL-Tx-2019-NCT-02243033.FINAL_.pdf">https://www.admetech.org/wp-content/uploads/2019/08/DMI-FOCAL-Tx-2019-NCT-02243033.FINAL_.pdf</a> (2020)</li><li>Chao, B., Llukani, E., Lepor, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two-year+Outcomes+Following+Focal+Laser+Ablation+of+Localized+Prostate+Cancer.">Two-year Outcomes Following Focal Laser Ablation of Localized Prostate Cancer.</a> European Urology Oncology. 1 (2), 129-133 (2018).</li></ol>

Dr. Marks and Dr. Natarajan are co-founders of Avenda Health.

The purpose of the present work is to describe and illustrate a method for performing focal laser ablation (FLA) of prostate cancer (PCa). The method differs from other focal therapy methods, as it is intended to be performed under local anesthesia in a clinic setting. The FLA method shown here was introduced in 2017,20 and has been continuously refined since that time. Thus, the procedure described in this paper may be of value to future investigators.
Laser treatment of prostate tissue appears to date from the research of McNicholas and colleagues, working at University College London, who demonstrated in 1993 that focal coagulation necrosis could be produced in canine prostates with a Nd:YAG device.32 Foreshadowing the future, these authors postulated that the technique &#34;&#8230;may prove of value&#8230;for the destruction of small focal prostatic tumors.&#34; Subsequently, laser ablation of PCa in man was described in 2009 by Lindner et al from the University of Toronto.26 In that pioneering effort, Lindner combined the emerging modality of prostate MRI with early image-fusion software and conventional thermal probes to successfully target cancer and monitor laser ablation in 12 men.
Since most important PCa can be visualized with contemporary multi-parametric MRI, in-bore targeting and treatment of visible lesions might be a straightforward extension of the diagnostic procedure. In-bore targeting of the lesion is direct, and MR thermometry allows remote monitoring of ablation. Raz et al reported two such treatments in 2010.33 A series of in-bore FLA treatments (N=9) was reported by Oto and colleagues in 2013.5 Adoption of in-bore FLA has been facilitated by hardware developed for that purpose, as reported by Natarajan et al in 2016.19 A number of radiologists, using a water-cooled laser fiber to prevent charring have adopted the in-bore method; and hundreds of in-bore FLA treatments have now been reported (Walser, Feller, Sperling/Lepor).6, 16, 34, 35
While short term oncologic outcomes of in-bore FLA may be favorable (Table 1), the procedure is not likely to become widely adopted, because of limiting factors described in the introduction. Moreover, MR thermometry for treatment monitoring exhibits a number of important limitations.19 Building on a decade-long experience with MRI/US fusion biopsy procedures (N~4000), we theorized that a laser fiber could be targeted into a cancer lesion, similarly to inserting a biopsy needle, and that monitoring of treatment could be accomplished directly with thermal probes. Thus, following the in-bore experience, ten patients underwent out-of-bore FLA in the UCLA urology clinic, using only local anesthesia, MRI/US fusion guidance, and thermal-probe monitoring.20 Not only was safety and feasibility of the new method demonstrated, but among the latter patients treated, no evidence of PCa could be found at subsequent biopsy.
The tissue effect of FLA has been clarified in two studies, where planned radical prostatectomy was performed 1-3 weeks after the laser procedure (N=9), i.e., a &#39;treat-and-resect&#39; model (Figure 4).15, 27 In all 9 patients, the volume of necrotic tissue found in the prostate approximated the volume estimated by the MRI obtained after completion of treatment. When the whole prostates were sectioned, an abrupt transition was seen between necrosis and intact cells 1-5 mm outside of the area of laser ablation (Figure 1). The crisp margins and precision of the ablation zones have important implications for the accuracy of MRI/US registration and treatment planning.
A major part of the Avenda system is the treatment planning software. For effective FLA, the planning needs to include not only the location of the lesion, but also the volume of tissue necessary for complete tumor destruction. The ablation volume cannot simply be the MRI-lesion volume, because the actual tumor volume exceeds that of the MRI-visible lesion by an average of 3-fold.21 Moreover, cancer often extends in irregular finger-like projections, which would make unreliable any uniform safety margin based solely on imaging (e.g., 1 cm beyond boundary of MRI-visible lesion). The Avenda system includes treatment planning software that utilizes not only the MRI-visible lesion, but also 3D tracking of biopsy sites (positive and negative) to provide accurate placement of the minimal ablation volume that will fully encompass the cancer. An example of such treatment planning is seen in Figure 3.
In conclusion, FLA is a safe, feasible method for eradicating prostate cancer in a clinic setting under local anesthesia. Steps of the procedure are shown in the accompanying video. Accurate placement of the laser fiber into an MRI-visible lesion is accomplished using MRI/US fusion, much as biopsy needles are place into such lesions. Realtime treatment monitoring is accomplished via a thermal probe adjacent to the laser fiber. Treatment planning software, which employs lesion volumes from MRI and tracked biopsy site locations to help the operator determine treatment margins, is an important part of the system. In-clinic FLA as described and illustrated in this article appears to provide an attractive focal therapy option not previously available.

Prostate cancer (PCa) is the most common internal malignancy in U.S. men1. Approximately 190,000 new cases and 33,000 deaths are expected during 2020, making it the second most common cause of cancer death in men2. Most cases of PCa are curable if treated while localized to the prostate. However, identifying cancer within the prostate is often not possible with conventional ultrasound (US) imaging; thus, treatment has traditionally involved surgery or radiation of the whole gland. The &#39;whole-gland&#39; paradigm has been altered with the introduction of magnetic resonance imaging (MRI), which, in contrast to US, enables localization of PCa and targeted biopsy3,4,5,6. While MRI likely underestimates the multifocality of PCa7, and may miss small lesions8, it can reliably identify the index lesion, which is almost always the driver of metastatic disease9, 10.
Reliable MRI identification of index lesions has provided a path for focal treatment of PCa (i.e., partial gland ablation (PGA)). The aim of PGA is to destroy the index lesion while preserving the organ and thus minimizing side effects. Focal laser ablation (FLA), which employs light energy to destroy tissue through coagulative necrosis11, 12, is one form of PGA. The effectiveness of laser energy to ablate prostate tissue was established in 199313, suggesting the placement of laser fibers into prostate cancers for that purpose. Using MRI for guidance of fiber placement and MRI thermography for treatment monitoring (i.e., in-bore treatment), near-term success rates of FLA appear to approach those of surgery or radiation5, 6, 12, 14,15,16,17,18,19. However, laser procedures performed in-bore, or within an MRI tube, are often cumbersome, expensive, time-consuming, and resource-intensive. And in-bore procedures are only performed by sub-specialty trained radiologists.
As an alternative to in-bore FLA, the feasibility of performing FLA in a clinic setting---using MRI/US fusion for guidance and an interstitial temperature probe for treatment monitoring--- has been under study at UCLA since 201419, 20. The FLA procedure in a clinic setting has proven to be similar to that of targeted biopsy, substituting a laser fiber for a biopsy needle. In comparison with HIFU and cryotherapy, which are the other currently available methods of PGA, the laser method described here is quick and inexpensive, without need for an operating room or general anesthesia.
This article aims to describe and demonstrate outpatient FLA under local anesthesia in a urology clinic. Urologists who are familiar with MRI/US fusion for targeted biopsy will appreciate the similarities of FLA to the biopsy procedure. Secondary objectives include describing technical elements that facilitate ease of use and describing benefits of focal therapy.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Fusion Guidance System</td>
			<td>NA</td>
			<td></td>
			<td>Artemis Displayed in Video</td>
		</tr>
		<tr>
			<td>Laser Catheter</td>
			<td>Avenda Health</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Orion Workstation</td>
			<td>Avenda Health</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Thermal Probe</td>
			<td>Avenda Health</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Transrectal Probe</td>
			<td>NA</td>
			<td></td>
			<td>Not Platform Dependent</td>
		</tr>
		<tr>
			<td>Ultrasound</td>
			<td>NA</td>
			<td></td>
			<td>Not Platform Dependent</td>
		</tr>
	</tbody>
</table>

focal laser ablation of prostate cancer: an office procedure

In this article, we describe and illustrate an outpatient procedure for focal laser ablation (FLA) of prostate cancer (PCa). The procedure is conceptually similar to a fusion biopsy and is performed under local anesthesia in a clinic setting; treatment time is usually less than one hour. Laser insertion is guided by ultrasound; lesion targeting is via magnetic resonance imaging-ultrasound (MRI/US) fusion, as in targeted prostate biopsy. Real-time ablation monitoring is achieved utilizing a thermal probe adjacent to the laser fiber. The video demonstrates procedure planning, patient preparation, various steps during the procedure, and treatment monitoring. Safety, feasibility, and efficacy of this approach have been established during a previous trial. Outpatient FLA under local anesthesia is an option for management of intermediate risk prostate cancer.

The published results of FLA are shown in Table 2. A variety of methods and technologies are included. More than 400 patients who have undergone various forms of FLA for treatment of PCa are found within the SEER database.25 To quantify the number and characteristics of FLA reported in the literature we performed a systematic review of Medline and the Cochrane Library. Our search was performed using whole-field search terms including &#34;focal laser ablation&#34; and &#34;prostate cancer.&#34; In total, 247 titles and abstracts were reviewed. Only cases reporting focal laser ablation, MRI, and oncologic outcomes were included. 13 peer-reviewed publications qualified for inclusion, representing 333 total patients (Table 1).
Treatment was performed with a 980 nm diode laser in all but 2 studies.26, 27 Treatment parameters consisted of power levels between 6 - 18 Watts and treatment times spanning 1 - 4 minutes per ablation site (Table 1). Treatment temperature monitoring was supplied by MRI thermometry in 9 studies and by direct temperature probe measurements in 3 studies (Table 1). All studies were performed in-bore, except those by Lindner and the later study by Natarajan.20, 26, 27
Median baseline PSA for the cohort was 5.7 (range 1.1 - 14.8). Following FLA, median PSA at 3, 6, 12 and 24 months was 3.9, 5.5, 3.8, and 3.9 respectively. Median baseline IPSS for the cohort was 6. Following FLA, median IPSS at 3, 6, 12 and 24 months was 5, 5.5, 7.3 and 11.5 respectively. Median baseline SHIM for the cohort was 20. Following FLA, median SHIM at 3, 6, 12 and 24 months was 19, 18, 20, and 19 respectively.
Across all studies, complications were inconsistently reported; however there was only one complication classified by the authors as Grade III (a urinary tract infection).16 The authors did not specify the features that classified this as a grade III event. Two recto-urethral fistulas, both closing spontaneously after prolonged catheterization,16 were reported as grade II adverse events.
Oncologic follow up was grouped by follow-up period: less than 6 months, one year, and two years (Table 2). Follow up biopsy was performed by MRI guided in-bore biopsy in 4 studies, and MRI-US fusion biopsy in 6 studies. Two studies utilized systematic biopsy and two studies performed &#39;treat-and-resect&#39; investigations where the prostatectomy specimen was evaluated. Treatment success was defined according to a Delphi consensus protocol.28 In-field success was defined as the absence of &#8805; GG2 PCa within the prior ablation site. Out of field failure was defines as &#8805; GG2 outside the area of prior ablation. Among patients with follow up biopsy results, overall in-field success following treatment at 6 months (N=83), 1 year (N=64) and 2 years (N=39) was 83%, 83%, and 59% respectively (Table 2).
At UCLA, FLA of the prostate has been performed in three successive clinical trials starting in 2014.29-31 18 men with intermediate risk prostate cancer have undergone FLA, eight in-bore and 10 in clinic, without any grade III adverse events. Currently, an additional 10 men are undergoing FLA using the demonstrated device.31 All patients were evaluated before FLA with a 3T MRI (body coil), and MRI-US fusion biopsy with sampling from the ROI and systematic biopsy within 6 months of treatment. Both baseline and follow up biopsies were performed under MRI/US fusion guidance using the Artemis fusion system with tracking of all biopsy sites.
Table 1.&#160;Reported studies of focal laser ablation.&#160;
<table border="1" fo:font-size="8px" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td rowspan="2">Reference Number</td>
			<td rowspan="2">Author</td>
			<td rowspan="2">&#160;Year</td>
			<td rowspan="2">N</td>
			<td rowspan="2">Median Age (Range)</td>
			<td rowspan="2">Laser Power</td>
			<td rowspan="2">Rx Time (sec)</td>
			<td rowspan="2">Planned Margin</td>
			<td rowspan="2">In-Bore Procedure</td>
			<td colspan="2" rowspan="2">Temperature Monitoring</td>
			<td colspan="4">Baseline Gleason</td>
		</tr>
		<tr>
			<td>3+3</td>
			<td>3+4</td>
			<td>4+3</td>
			<td>4+4</td>
		</tr>
		<tr>
			<td>26</td>
			<td>Lindner</td>
			<td>2009</td>
			<td>12</td>
			<td>56.5 (51-52)</td>
			<td>-</td>
			<td>120</td>
			<td>-</td>
			<td>No</td>
			<td colspan="2">Temperature probe</td>
			<td>12</td>
			<td>0</td>
			<td>0</td>
			<td>0</td>
		</tr>
		<tr>
			<td>27</td>
			<td>Lindner</td>
			<td>2010</td>
			<td>4</td>
			<td>66 (61-73)</td>
			<td>-</td>
			<td>120</td>
			<td>-</td>
			<td>No</td>
			<td colspan="2">Temperature probe</td>
			<td>2</td>
			<td>0</td>
			<td>1</td>
			<td>1</td>
		</tr>
		<tr>
			<td>5</td>
			<td>Oto</td>
			<td>2013</td>
			<td>9</td>
			<td>61 (52-77)</td>
			<td>6 - 15 W</td>
			<td>-</td>
			<td>-</td>
			<td>Yes</td>
			<td colspan="2">MRI Thermometry</td>
			<td>8</td>
			<td>1</td>
			<td>0</td>
			<td>0</td>
		</tr>
		<tr>
			<td>12</td>
			<td>Lee</td>
			<td>2014</td>
			<td>23</td>
			<td>-</td>
			<td>8 W</td>
			<td>30-60</td>
			<td>-</td>
			<td>Yes</td>
			<td colspan="2">MRI Thermometry</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
		</tr>
		<tr>
			<td>6</td>
			<td>Lepor</td>
			<td>2015</td>
			<td>25</td>
			<td>66 (49-84)</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>Yes</td>
			<td colspan="2">MRI Thermometry</td>
			<td>11</td>
			<td>13</td>
			<td>1</td>
			<td>0</td>
		</tr>
		<tr>
			<td>18</td>
			<td>Al Barqawi</td>
			<td>2015</td>
			<td>7</td>
			<td>61 (56-69)</td>
			<td>-</td>
			<td>90</td>
			<td>-</td>
			<td>Yes</td>
			<td colspan="2">MRI Thermometry</td>
			<td>7</td>
			<td>0</td>
			<td>0</td>
			<td>0</td>
		</tr>
		<tr>
			<td>15</td>
			<td>Bomers</td>
			<td>2016</td>
			<td>5</td>
			<td>66 (58-70)</td>
			<td>-</td>
			<td>-</td>
			<td>9 mm</td>
			<td>Yes</td>
			<td colspan="2">MRI Thermometry</td>
			<td>2</td>
			<td>2</td>
			<td>1</td>
			<td>0</td>
		</tr>
		<tr>
			<td>14</td>
			<td>Eggener</td>
			<td>2016</td>
			<td>27</td>
			<td>62 (-)</td>
			<td>6 - 15 W</td>
			<td>60-120</td>
			<td>0 -7.5mm</td>
			<td>Yes</td>
			<td colspan="2">MRI Thermometry</td>
			<td>23</td>
			<td>3</td>
			<td>1</td>
			<td>0</td>
		</tr>
		<tr>
			<td>19</td>
			<td>Natarajan</td>
			<td>2016</td>
			<td>8</td>
			<td>63 (54-72)</td>
			<td>11 - 14 W</td>
			<td>180</td>
			<td>Custom*</td>
			<td>Yes</td>
			<td colspan="2">Temperature probe #</td>
			<td>1</td>
			<td>7</td>
			<td>0</td>
			<td>0</td>
		</tr>
		<tr>
			<td>20</td>
			<td>Natarajan</td>
			<td>2017</td>
			<td>10</td>
			<td>65 (52-74)</td>
			<td>13.75 W</td>
			<td>180</td>
			<td>Custom*</td>
			<td>No</td>
			<td colspan="2">Temperature probe</td>
			<td>2</td>
			<td>8</td>
			<td>0</td>
			<td>0</td>
		</tr>
		<tr>
			<td>35</td>
			<td>Chao</td>
			<td>2018</td>
			<td>34</td>
			<td>69 (52-88)</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>Yes</td>
			<td colspan="2">MRI Thermometry</td>
			<td>16</td>
			<td>16</td>
			<td>2</td>
			<td>0</td>
		</tr>
		<tr>
			<td>17</td>
			<td>Al Hakeem</td>
			<td>2019</td>
			<td>49</td>
			<td>63 (51-73)</td>
			<td>10 - 15 W</td>
			<td>120</td>
			<td>9 mm</td>
			<td>Yes</td>
			<td colspan="2">MRI Thermometry</td>
			<td>13</td>
			<td>29</td>
			<td>7</td>
			<td>0</td>
		</tr>
		<tr>
			<td>16</td>
			<td>Walser</td>
			<td>2019</td>
			<td>120</td>
			<td>60 (45-86)</td>
			<td>17 - 18 W</td>
			<td>180-240</td>
			<td>5 mm</td>
			<td>Yes</td>
			<td colspan="2">MRI Thermometry</td>
			<td>37</td>
			<td>56</td>
			<td>27</td>
			<td>0</td>
		</tr>
	</tbody>
</table>
Table 1: Dash (-) indicates information not available within the published manuscript. * indicates each margin was planned individually. # indicates monitoring was performed with both a temperature probe and MRI thermometry.
Table 2. Outcomes of focal laser ablation.&#160;
<table border="1" fo:font-size="8px" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td rowspan="2">Reference Number</td>
			<td rowspan="2">First Author</td>
			<td colspan="2" rowspan="2">Follow Up Biopsy Method</td>
			<td rowspan="2">Follow up Biopsy</td>
			<td colspan="2">&#8804; 6 Months</td>
			<td colspan="2">12 Months</td>
			<td colspan="2">24 Months</td>
			<td colspan="3">Adverse Events</td>
		</tr>
		<tr>
			<td>Success</td>
			<td>Failure</td>
			<td>Success</td>
			<td>Failure</td>
			<td>Success</td>
			<td>Failure</td>
			<td>I</td>
			<td>II</td>
			<td>III</td>
		</tr>
		<tr>
			<td>26</td>
			<td>Lindner</td>
			<td colspan="2">MRI Guided Bx</td>
			<td>12</td>
			<td>12</td>
			<td>0</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>2</td>
			<td>0</td>
			<td>0</td>
		</tr>
		<tr>
			<td>27</td>
			<td>Lindner</td>
			<td colspan="2">Prostatectomy</td>
			<td>4</td>
			<td>2</td>
			<td>2</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
		</tr>
		<tr>
			<td>5</td>
			<td>Oto</td>
			<td colspan="2">MRI/US Bx</td>
			<td>9</td>
			<td>9</td>
			<td>0</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>1</td>
			<td>1</td>
			<td>0</td>
		</tr>
		<tr>
			<td>12</td>
			<td>Lee</td>
			<td colspan="2">MRI/US Bx</td>
			<td>13</td>
			<td>-</td>
			<td>-</td>
			<td>12</td>
			<td>1</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
		</tr>
		<tr>
			<td>6</td>
			<td>Lepor</td>
			<td colspan="2">MRI Guided Bx</td>
			<td>21</td>
			<td>20</td>
			<td>1</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>0</td>
			<td>0</td>
			<td>0</td>
		</tr>
		<tr>
			<td>18</td>
			<td>Al Barqawi</td>
			<td colspan="2">Systematic Bx</td>
			<td>5</td>
			<td>-</td>
			<td>-</td>
			<td>5</td>
			<td>00</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>1</td>
			<td>0</td>
		</tr>
		<tr>
			<td>15</td>
			<td>Bomers</td>
			<td colspan="2">Prostatectomy</td>
			<td>5</td>
			<td>1</td>
			<td>4</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
		</tr>
		<tr>
			<td>14</td>
			<td>Eggener</td>
			<td colspan="2">MRI Guided Bx #</td>
			<td>27</td>
			<td>27</td>
			<td>-</td>
			<td>7</td>
			<td>31</td>
			<td>-</td>
			<td>-</td>
			<td>7</td>
			<td>2</td>
			<td>0</td>
		</tr>
		<tr>
			<td>19</td>
			<td>Natarajan</td>
			<td colspan="2">MRI/US Bx</td>
			<td>8</td>
			<td>6</td>
			<td>53</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>23</td>
			<td>7</td>
			<td>0</td>
		</tr>
		<tr>
			<td>20</td>
			<td>Natarajan</td>
			<td colspan="2">MRI/US Bx</td>
			<td>10</td>
			<td>6</td>
			<td>40</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>38</td>
			<td>6</td>
			<td>0</td>
		</tr>
		<tr>
			<td>35</td>
			<td>Chao</td>
			<td colspan="2">MRI/US Bx</td>
			<td>22</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>13</td>
			<td>9</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
		</tr>
		<tr>
			<td>17</td>
			<td>Al Hakeem</td>
			<td colspan="2">MRI/US Bx</td>
			<td>49</td>
			<td>-</td>
			<td>-</td>
			<td>40</td>
			<td>91</td>
			<td>-</td>
			<td>-</td>
			<td>34</td>
			<td>11</td>
			<td>0</td>
		</tr>
		<tr>
			<td>16</td>
			<td>Walser</td>
			<td colspan="2">MRI Guided Bx</td>
			<td>44*</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
			<td>26</td>
			<td>18</td>
			<td>8</td>
			<td>8</td>
			<td>1</td>
		</tr>
	</tbody>
</table>
Footnotes Table 2. Success = absence of &#8805; GG2 prostate cancer within the ablation zone. Failure = presence of &#8805; GG2 prostate cancer: total and out-of-field (subscript number). # indicates MRI guided biopsy was used for 6 months biopsy but only systematic biopsy was used for 12-month biopsy. * indicates that only patients with a PSA reduction of &#60; 50% and positive post ablation MRI underwent biopsy; 76 patients did not undergo biopsy.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/61984/61984fig01.jpg" /> 
Figure 1: Treatment Planning and Assessment, shown via overlays on transverse MRI (top row) and in 3D (bottom row). Column A shows the delineation of treatment margins, which are expanded around the cancer-positive MRI target and bounded by nearby negative systematic biopsy cores (blue). Column B shows planning of ablation locations such that the treatment margins are overlapped to prevent &#39;skip&#39; areas. Column C shows perfusion-weighted imaging collected 2 hours post-treatment, demonstrating correspondence between the planned and observed ablation extent. <a href="https://www.jove.com/files/ftp_upload/61984/61984fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/61984/61984fig02.jpg" /> 
Figure 2: Axial ultrasound with prostate outlined in gold. Corner cube reflectors (echogenic bands), indicated by dotted arrows, are etched into the laser catheter 5 mm from the diffuser (white). Temperature probe is inserted to the same depth as the laser fiber, then locked into place and remains parallel to the laser 8 mm apart, out of the US plane of view. Eight thermal sensors, which are within the probe 4 mm apart, provide temperature recordings at points from the base of the echogenic bands to the tip of the laser catheter. Temperature measurements closest to the rectal wall are provided by thermal measurements at the base of the temperature probe (positions 6-8). <a href="https://www.jove.com/files/ftp_upload/61984/61984fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/61984/61984fig03.jpg" /> 
Figure 3: Temperature recordings during focal laser ablation for two successive ablations. Y-axis = temperature in Celsius. X-axis = time in minutes. Vertical shaded bars = periods of laser activation. Blue line = temperature 8mm from tip of laser fiber (distal thermocouple). White line = temperature 8 mm from proximal thermocouple nearest the rectal wall. A temperature of 60 degrees Celsius, achieved even briefly, assures coagulation necrosis. <a href="https://www.jove.com/files/ftp_upload/61984/61984fig03large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/61984/61984fig04.jpg" /> 
Figure 4: Images demonstrating concordance of ablation zone on post-treatment MRI (A) with actual necrotic zone on whole-mount specimen (B). Patient is 67-year-old male with PCa in right transition zone, Gleason score 3 + 4 = 7, participating in a &#39;treat and resect&#39; trial. A. Post-ablation axial T1-weighted contrast-enhanced image, showing perfusion defect caused by laser treatment (green). B. Whole-mount H&#38;E stain of the prostate. The necrotic tissue is delineated in green, the peri-necrotic tissue in yellow, and intact tumor (untreated) in blue. Reproduced under a Creative Commons license from Bomers et al, World Journal of Urology.15&#160; <a href="https://www.jove.com/files/ftp_upload/61984/61984fig04large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

Watch this Scientific Journal Video about Focal Laser Ablation of Prostate Cancer: An Office Procedure at JoVE.com

Focal Laser Ablation of Prostate Cancer: An Office Procedure

This article presents and describes an outpatient treatment for prostate cancer using focal laser ablation. Laser catheter placement is guided by MRI-ultrasound fusion imaging in a fashion similar to prostate needle biopsy. Treatment is monitored in real-time with a thermal probe, placed adjacent to the laser fiber.

In this article, we describe and illustrate an outpatient procedure for focal laser ablation (FLA) of prostate cancer (PCa). The procedure is conceptually ...

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7.5K Views.  University of California Los Angeles. This article presents and describes an outpatient treatment for prostate cancer using focal laser ablation. Laser catheter placement is guided by MRI-ultrasound fusion imaging in a fashion similar to prostate needle biopsy. Treatment is monitored in real-time with a thermal probe, placed adjacent to the laser fiber. 

Video: Focal Laser Ablation of Prostate Cancer: An Office Procedure

Evaluation of Nanoparticle Uptake in Tumors in Real Time Using Intravital Imaging

Current technologies for tumor imaging, such as ultrasound, MRI, PET and CT, are unable to yield high-resolution images for the assessment of nanoparticle uptake in tumors at the microscopic level1,2,3, highlighting the utility of a suitable xenograft model in which to perform detailed uptake analyses. Here, we use high-resolution intravital imaging to evaluate nanoparticle uptake in human tumor xenografts in a modified, shell-less chicken embryo model. The chicken embryo model is particularly well-suited for these in vivo analyses because it supports the growth of human tumors, is relatively inexpensive and does not require anesthetization or surgery 4,5. Tumor cells form fully vascularized xenografts within 7 days when implanted into the chorioallantoic membrane (CAM) 6. The resulting tumors are visualized by non-invasive real-time, high-resolution imaging that can be maintained for up to 72 hours with little impact on either the host or tumor systems. Nanoparticles with a wide range of sizes and formulations administered distal to the tumor can be visualized and quantified as they flow through the bloodstream, extravasate from leaky tumor vasculature, and accumulate at the tumor site. We describe here the analysis of nanoparticles derived from Cowpea mosaic virus (CPMV) decorated with near-infrared fluorescent dyes and/or polyethylene glycol polymers (PEG) 7, 8, 9,10,11. Upon intravenous administration, these viral nanoparticles are rapidly internalized by endothelial cells, resulting in global labeling of the vasculature both outside and within the tumor7,12. PEGylation of the viral nanoparticles increases their plasma half-life, extends their time in the circulation, and ultimately enhances their accumulation in tumors via the enhanced permeability and retention (EPR) effect 7, 10,11. The rate and extent of accumulation of nanoparticles in a tumor is measured over time using image analysis software. This technique provides a method to both visualize and quantify nanoparticle dynamics in human tumors.

We present a novel approach to quantify nanoparticle localization in the vasculature of human xenografted tumors using dynamic, real-time intravital imaging in an avian embryo model.

Current technologies for tumor imaging, such as ultrasound, MRI, PET and CT, are unable to yield high-resolution images for the assessment of nanoparticle ...

MR Molecular Imaging of Prostate Cancer with a Small Molecular CLT1 Peptide Targeted Contrast Agent

Tumor extracellular matrix has abundance of cancer related proteins that can be used as biomarkers for cancer molecular imaging. In this work, we demonstrated effective MR cancer molecular imaging with a small molecular peptide targeted Gd-DOTA monoamide complex as a targeted MRI contrast agent specific to clotted plasma proteins in tumor stroma. We performed the experiment of evaluating the effectiveness of the agent for non-invasive detection of prostate tumor with MRI in a mouse orthotopic PC-3 prostate cancer model. The targeted contrast agent was effective to produce significant tumor contrast enhancement at a low dose of 0.03 mmol Gd/kg. The peptide targeted MRI contrast agent is promising for MR molecular imaging of prostate tumor.

To demonstrate MR cancer molecular imaging with a small peptide targeted MRI contrast agent specific to clotted plasma proteins in tumor stroma in a mouse prostate cancer model.

Tumor extracellular  matrix has abundance of cancer related proteins that can be used as biomarkers  for cancer molecular imaging. In this work,  we ...

An Orthotopic Murine Model of Human Prostate Cancer Metastasis

Our laboratory has developed a novel orthotopic implantation model of human prostate cancer (PCa). As PCa death is not due to the primary tumor, but rather the formation of distinct metastasis, the ability to effectively model this progression pre-clinically is of high value. In this model, cells are directly implanted into the ventral lobe of the prostate in Balb/c athymic mice, and allowed to progress for 4-6 weeks. At experiment termination, several distinct endpoints can be measured, such as size and molecular characterization of the primary tumor, the presence and quantification of circulating tumor cells in the blood and bone marrow, and formation of metastasis to the lung. In addition to a variety of endpoints, this model provides a picture of a cells ability to invade and escape the primary organ, enter and survive in the circulatory system, and implant and grow in a secondary site. This model has been used effectively to measure metastatic response to both changes in protein expression as well as to response to small molecule therapeutics, in a short turnaround time.

This orthotopic model of human prostate cancer allows for quantification of tumor size, circulating tumor cells, and formation of distinct metastasis to the lung. As cells must escape the primary organ, enter the blood stream, and implant into a secondary site, this model effectively recapitulates the scenario in humans.

Our laboratory has developed a novel orthotopic implantation model of  human prostate cancer (PCa). As PCa death is not due to the primary tumor, but  ...

Isolation of Cancer Stem Cells From Human Prostate Cancer Samples

The cancer stem cell (CSC) model has been considerably revisited over the last two decades. During this time CSCs have been identified and directly isolated from human tissues and serially propagated in immunodeficient mice, typically through antibody labeling of subpopulations of cells and fractionation by flow cytometry. However, the unique clinical features of prostate cancer have considerably limited the study of prostate CSCs from fresh human tumor samples. We recently reported the isolation of prostate CSCs directly from human tissues by virtue of their HLA class I (HLAI)-negative phenotype. Prostate cancer cells are harvested from surgical specimens and mechanically dissociated. A cell suspension is generated and labeled with fluorescently conjugated HLAI and stromal antibodies. Subpopulations of HLAI-negative cells are finally isolated using a flow cytometer. The principal limitation of this protocol is the frequently microscopic and multifocal nature of primary cancer in prostatectomy specimens. Nonetheless, isolated live prostate CSCs are suitable for molecular characterization and functional validation by transplantation in immunodeficient mice.

The isolation of cancer stem cells (CSCs) directly from human tissues is requisite for their biological characterization. This manuscript describes a methodology for the isolation of prostate CSCs from human tissues, while also providing tips on troubleshooting difficult steps.

The cancer stem cell (CSC) model has been considerably revisited over the last two decades. During this time CSCs have been identified and directly ...

An &#8220;All-laser&#8221; Endothelial Transplant

The &#8220;all laser&#8221; assisted endothelial keratoplasty is a procedure that is performed with a femtosecond laser used to cut the donor tissue at an intended depth, and a near infrared diode laser to weld the corneal tissue. The proposed technique enables to reach the three main goals in endothelial keratoplasty: a precise control in the thickness of the donor tissue; its easy insertion in the recipient bed and a reduced risk of donor lenticule dislocation. The donor cornea thickness is measured in the surgery room with optical coherence tomography (OCT), in order to correctly design the donor tissue dimensions. A femtosecond laser is used to cut the donor cornea. The recipient eye is prepared by manual stripping of the descemetic membrane. The donor endothelium is inserted into a Busin-injector, the peripheral inner side is stained with a proper chromophore (a water solution of Indocyanine Green) and then it is pulled in the anterior chamber. The transplanted tissue is placed in the final and correct location and then diode laser welding is induced from outside the eyeball. The procedure has been performed on more than 15 patients evidencing an improvement in surgery performances, with a good recovery of visual acuity and a reduced donor lenticule dislocation event.

An &amp;#8220;All-laser&amp;#8221; Endothelial Transplant

An all laser procedure is proposed in the endothelial transplant. The surgical technique is based on the use of a femtosecond laser to prepare the donor tissue. Laser welding technique is then used to secure the donor endothelium in the correct position.

The &#8220;all laser&#8221; assisted endothelial keratoplasty is a procedure that is performed with a femtosecond laser used to cut the donor tissue at an ...

miRNA Expression Analyses in Prostate Cancer Clinical Tissues

A critical challenge in prostate cancer (PCa) clinical management is posed by the inadequacy of currently used biomarkers for disease screening, diagnosis, prognosis and treatment. In recent years, microRNAs (miRNAs) have emerged as promising alternate biomarkers for prostate cancer diagnosis and prognosis. However, the development of miRNAs as effective biomarkers for prostate cancer heavily relies on their accurate detection in clinical tissues. miRNA analyses in prostate cancer clinical specimens is often challenging owing to tumor heterogeneity, sampling errors, stromal contamination etc. The goal of this article is to describe a simplified workflow for miRNA analyses in archived FFPE or fresh frozen prostate cancer clinical specimens using a combination of quantitative real-time PCR (RT-PCR) and in situ hybridization (ISH). Within this workflow, we optimize the existing methodologies for miRNA extraction from FFPE and frozen prostate tissues and expression analyses by Taqman-probe based miRNA RT-PCR. In addition, we describe an optimized method for ISH analyses formiRNA detection in prostate tissues using locked nucleic acid (LNA)- based probes. Our optimized miRNA ISH protocol can be applied to prostate cancer tissue slides or prostate cancer tissue microarrays (TMA).

Here we describe a simplified protocol for microRNA (miRNA) expression analyses in archived Formalin-Fixed, Paraffin-Embedded (FFPE) or fresh frozen prostate cancer (PCa) clinical tissues employing quantitative real-time PCR (RT-PCR) and in situ hybridization (ISH).

A critical challenge in prostate cancer (PCa) clinical management is posed by the inadequacy of currently used biomarkers for disease screening, ...

Generation of Prostate Cancer Patient Derived Xenograft Models from Circulating Tumor Cells

Patient derived xenograft (PDX) models are gaining popularity in cancer research and are used for preclinical drug evaluation, biomarker identification, biologic studies, and personalized medicine strategies. Circulating tumor cells (CTC) play a critical role in tumor metastasis and have been isolated from patients with several tumor types. Recently, CTCs have been used to generate PDX experimental models of breast and prostate cancer. This manuscript details the method for the generation of prostate cancer PDX models from CTCs developed by our group. Advantages of this method over conventional PDX models include independence from surgical sample collection and generating experimental models at various disease stages. Density gradient centrifugation followed by red blood cell lysis and flow cytometry depletion of CD45 positive mononuclear cells is used to enrich CTCs from peripheral blood samples collected from patients with metastatic disease. The CTCs are then injected into immunocompromised mice; subsequently generated xenografts can be used for functional studies or harvested for molecular characterization. The primary limitation of this method is the negative selection method used for CTC enrichment. Despite this limitation, the generation of PDX models from CTCs provides a novel experimental model to be applied to prostate cancer research.

This manuscript details a method used to generate prostate cancer patient derived xenografts (PDXs) from circulating tumor cells (CTCs). The generation of PDX models from CTCs provides an alternative experimental model to study prostate cancer; the most commonly diagnosed tumor and a frequent cause of death from cancer in men.

Patient derived xenograft (PDX) models are gaining popularity in cancer research and are used for preclinical drug evaluation, biomarker identification, ...

Pre-clinical Orthotopic Murine Model of Human Prostate Cancer

To study the multifaceted biology of prostate cancer, pre-clinical in vivo models offer a range of options to uncover critical biological information about this disease. The human orthotopic prostate cancer xenograft mouse model provides a useful alternative approach for understanding the specific interactions between genetically and molecularly altered tumor cells, their organ microenvironment, and for evaluation of efficacy of therapeutic regimens. This is a well characterized model designed to study the molecular events of primary tumor development and it recapitulates the early events in the metastatic cascade prior to embolism and entry of tumor cells into the circulation. Thus it allows elucidation of molecular mechanisms underlying the initial phase of metastatic disease. In addition, this model can annotate drug targets of clinical relevance and is a valuable tool to study prostate cancer progression. In this manuscript we describe a detailed procedure to establish a human orthotopic prostate cancer xenograft mouse model.

Prostate cancer is the second most common cause of cancer-related deaths in the United States. An orthotopic cancer model provides a useful approach to understand the biology of prostate cancer and to evaluate the efficacy of therapeutic regimens. This protocol describes detailed steps necessary to establish an orthotopic prostate cancer mouse model.

To study the multifaceted biology of prostate cancer, pre-clinical in vivo models offer a range of options to uncover critical biological information ...

Surgical Treatment for Benign Prostatic Hyperplasia: Holmium Laser Enucleation of the Prostate (HoLEP).

Benign prostatic hyperplasia (BPH) commonly occurs among elderly males. The condition causes symptoms in the lower urinary tract, thereby reducing the quality of life. BPH includes 2 major treatments: medication and surgery. Surgical treatment is often the most effective and final intervention. Holmium laser enucleation of the prostate (HoLEP), one of the most efficient surgical procedures for BPH, is conducted transurethrally. During surgery, the most important and most difficult part is to locate the surgical capsule of the prostate, which is consistent to the idea of anatomic surgery. Different skills may be needed in treating different parts of the prostate. HoLEP tends to be efficient and safe with good hemostatic properties, and able to treat bladder calculus, which may be the complications of BPH. The technique is particularly suitable for prostate of varying volumes and sizes. Indeed, HoLEP also presents certain disadvantages, such as a long learning curve and costly equipment. Regardless, this method may be the "new standard" and the excellent method for the surgical treatment of BPH.

Surgical Treatment for Benign Prostatic Hyperplasia: Holmium Laser Enucleation of the Prostate HoLEP.

Here we present a safe and efficient protocol, holmium laser enucleation of the prostate, to treat benign prostatic hyperplasia.

Benign prostatic hyperplasia (BPH) commonly occurs among elderly males. The condition causes symptoms in the lower urinary tract, thereby reducing the ...

Photoselective Vaporesection of the Prostate via an End-firing Lithium Triborate Crystal Laser

The occurrence of lower urinary tract symptoms (LUTS) caused by benign prostatic hyperplasia (BPH) is a common problem with a high incidence in the aging male population. Although it is not a life-threatening disease, BPH causes problems that seriously impact the quality of life. Here, we introduce a new technique called photoselective vaporesection of the prostate (PVRP) in treating BPH, which can be seen as a variation of photoselective vaporization of the prostate (PVP). This procedure presents several advantages compared to the PVP technique including less laser energy loss, less intraoperative complications as well as more tissue resection rate.

Here we present a protocol to perform Photoselective Vaporesection of the Prostate (PVRP) for benign prostatic hyperplasia (BPH) treatment.

The occurrence of lower urinary tract symptoms (LUTS) caused by benign prostatic hyperplasia (BPH) is a common problem with a high incidence in the aging ...