This work does not have any funding sources.

This study was approved by the Ethics Committee of the Sixth Affiliated Hospital, Sun Yat-sen University. The diagnostic criteria and treatment strategies refer to Chinese guidelines for the diagnosis and comprehensive treatment of colorectal liver metastases (version 2018) and the Shanghai International Consensus on Diagnosis and Comprehensive Treatment of Colorectal Liver Metastases (Version 2019). The patient had clinical symptoms such as hematochezia, intestinal obstruction, liver pain, and weight loss. Patients with unresectable multiple liver metastases diagnosed by CT, MR, B-ultrasound, liver function, CEA, AFP, and other tumor markers were included in the study. The representative patient and their family have been informed of the contents of this agreement, the video shooting, and other relevant content; a signed informed consent form and authorization have been obtained from the patient.
1. Instruments for operation
<ol>
	<li>Before surgery, ensure that the surgical instruments mentioned in the Table of Materials are sterile, the surgical materials are complete, and the surgical equipment is normal.</li>
</ol>
2. Preparation for operation
<ol>
	<li>Prepare the belly button and skin for abdominal surgery. Clean the belly button and shave the belly hair.</li>
	<li>Bowel preparation: Ask patients to start consuming a residual-free diet, such as porridge and liquid foods, within 3 days before surgery, and guide them to take laxatives such as 139.12 g of compound polyethylene glycol electrolyte powder in 2,000 mL of warm water 1 day before the surgery. Ask the patient to have a clean enema on the night before surgery and in the morning on the day of surgery until all feces are discharged. The feces should be water samples without fecal residues. No food or drink is allowed for 8 h before the surgery. Insert a gastric tube for gastrointestinal decompression before the surgery.</li>
	<li>Ask the patient to lie supine on the operating table, and give general anesthesia with endotracheal intubation.</li>
	<li>Ensure the surgeons wash their hands during surgery, disinfect the operating area twice with 5% iodophenol, deiodize it once with 70% alcohol, and place surgical towels.</li>
	<li>At 30 min before the operation, administer 2.5 g of cefoperidine and sulbactam sodium and 100 mL of 0.9% sodium chloride solution intravenously.</li>
</ol>
3. Laparoscopic hepatectomy combined with intraoperative microwave ablation for colorectal cancer liver metastases
<ol>
	<li>Insert a 12&#160;cm trocar into the navel and abdominal cavity for aeration. Maintain the abdominal pressure at 12-15 mmHg, place 12 cm trocars under the xiphoid process and 15 cm below the costal margin of the right midclavicular line,&#160;and place two additional 5 cm trocars on the left and right sides (Figure 1).</li>
	<li>Place the laparoscope into the navel trocar to explore the cavity organs, such as the intestine, and the parenchymal organs, such as the liver in the abdominal cavity (Figure 2A). Separate the round and falciform ligaments associated with the abdominal wall and diaphragm of the liver using an ultrasonic knife (Figure 2B).</li>
	<li>Inject the contrast agent intravenously during the operation, and then place the laparoscopic ultrasound probe into the abdominal cavity from the two trocars 12 cm to explore the whole liver&#160;(Figure 3B).</li>
	<li>Under the effect of the contrast agent, locate the metastatic tumors in the S5 and S7 segments of the liver by ultrasound, and make localization markers on the liver surface (Figure 3A).</li>
	<li>For liver segments or liver lobes with less than three liver metastases, perform anatomic lobe or liver segment resection with an ultrasonic knife as per the portal vein drainage (Figure 4). Dissect the liver parenchyma of the left lateral lobe (Figure 4A), and sever the branch of the umbilical fissure vein (Figure 4B). Expose the hepatic pedicles between segment II and segment III (Figure 4C), and sever the left lateral lobe of the liver with a nail gun (Figure 4D).</li>
	<li>Use laparoscopic ultrasound to locate the boundaries of the tumor and to mark the surface of the liver (Figure 5A). Keep the margin of resection &#62;1 cm from the tumor, and perform the local liver parenchymal resection with an ultrasonic scalpel (Figure 5B).</li>
	<li>Detect liver metastases using laparoscopic ultrasound pressed to the liver surface (Figure 6A). Enter the microwave ablation needle into the abdominal cavity through the percutaneous puncture. This ensures that the laparoscopic puncture path avoids the thorax and surrounding organs and that ultrasound can be used to guide the microwave ablation needle into the tumor center for ablation. At the same time, microwave ablation under abdominal ultrasound can avoid important blood vessels and bile ducts in the liver (Figure 6B).</li>
	<li>Determine the metastatic lesions and the puncture site of microwave ablation by CT or B-ultrasound before the operation, and mark the surface puncture. After the localization of the metastasis, insert the microwave ablation needle into the abdominal cavity under direct laparoscopy.</li>
	<li>For metastatic tumors less than 3 cm in diameter, perform microwave ablation at 55 W power for 5 min by inserting a microwave ablation needle into the center of the metastatic tumor under the guidance of a laparoscopic ultrasound probe. 
	NOTE: Colorectal cancer liver metastases are mainly multiple liver metastases, and different treatments can be performed for different metastatic lesions. For metastatic lesions in the left lateral lobe, surgical resection can be performed if the remaining liver volume is sufficient. Microwave ablation can be used for metastatic lesions in occult sites that are difficult to resect or cannot be resected. Taking the ablation of a metastatic tumor in the S7 segment of the liver as an example, if the lesion is not easy to find with laparoscopic ultrasound, or the percutaneous puncture path needs to pass through the thorax or organs, it is necessary to free the perihepatic tough band (Figure 7A) and rotate the liver downward (Figure 7B) to expose the S7 segment of the liver. In this study, the metastatic tumor in segment S7 of the liver was re-located by ultrasound (Figure 7C), and thoracotomy was avoided. Microwave ablation needles were inserted into the center of the metastatic tumor, and ablation was performed under a specific power microwave ablation machine. Successful ablation was defined as liver tissue necrosis 3 cm away from the tumor center (this video is liver S7 segment ablation; Figure 7D).</li>
	<li>Electocoagulate the liver parenchyma sections with an ultrasonic scalpel, and place a hemostatic gauze (Figure 8A). Clean the abdominal cavity, and place a drainage tube (Figure 8D). Close the trocar pinhole with 2-0 polyglactin 910 sutures.</li>
</ol>
4. Postoperative care
<ol>
	<li>Ask the patient to fast, take parenteral nutrition, and perform early ambulation at 48 h after surgery.</li>
	<li>Perform ECG monitoring, pay attention to the patient&#39;s blood pressure, pulse, blood oxygen, and other vital signs, and review routine bloods, liver function, coagulation function, electrolytes, etc.</li>
	<li>Bleeding is likely to occur within 48 h after surgery. Closely observe whether there is abdominal pain, abdominal distension, tenderness, or rebound tenderness, and pay attention to the quantity, color, and character of the drainage fluid from the abdominal drainage tube. Note whether the patient has defecation exhaust.</li>
	<li>At 1 week after the surgery, discharge the patient from the hospital and instruct the patient to return to the hospital 1 month later for chemotherapy and an abdominal ultrasound review and to undergo microwave ablation again if necessary.</li>
</ol>

<ol>
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O., Vogl, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=[Ablative+modalities+in+the+treatment+of+liver+metastases].">[Ablative modalities in the treatment of liver metastases].</a> Zentralblatt fur Chirurgie. 144 (3), 259-263 (2019).</li><li>Stattner, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evolution+of+surgical+microwave+ablation+for+the+treatment+of+colorectal+cancer+liver+metastasis:+Review+of+the+literature+and+a+single+centre+experience.">Evolution of surgical microwave ablation for the treatment of colorectal cancer liver metastasis: Review of the literature and a single centre experience.</a> Surgery Today. 45 (4), 407-415 (2015).</li><li>Takahashi, H., Berber, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+thermal+ablation+in+the+management+of+colorectal+liver+metastasis.">Role of thermal ablation in the management of colorectal liver metastasis.</a> Hepatobiliary Surgery and Nutrition. 9 (1), 49-58 (2020).</li><li>Livraghi, T., Meloni, F., Solbiati, L., Zanus, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Collaborative+Italian+Group+using+AMICA+system.+Complications+of+microwave+ablation+for+liver+tumors:+Results+of+a+multicenter+study.">Collaborative Italian Group using AMICA system. Complications of microwave ablation for liver tumors: Results of a multicenter study.</a> Cardiovascular and Interventional Radiology. 35 (4), 868-874 (2012).</li><li>Kassahun, W. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Unresolved+issues+and+controversies+surrounding+the+management+of+colorectal+cancer+liver+metastasis.">Unresolved issues and controversies surrounding the management of colorectal cancer liver metastasis.</a> World Journal of Surgical Oncology. 13, 61 (2015).</li><li>Birrer, D. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multimodal+treatment+strategies+for+colorectal+liver+metastases.">Multimodal treatment strategies for colorectal liver metastases.</a> Swiss Medical Weekly. 151, w20390 (2021).</li><li>Stewart, C. 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When does it palliate, prolong survival, and potentially cure.</a> Current Problems in Surgery. 55 (9), 330-379 (2018).</li><li>Tanaka, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Outcome+after+hepatic+resection+versus+combined+resection+and+microwave+ablation+for+multiple+bilobar+colorectal+metastases+to+the+liver.">Outcome after hepatic resection versus combined resection and microwave ablation for multiple bilobar colorectal metastases to the liver.</a> Surgery. 139 (2), 263-273 (2006).</li><li>McNally, S. J., Parks, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surgery+for+colorectal+liver+metastases.">Surgery for colorectal liver metastases.</a> Digestive Surgery. 30 (4-6), 337-347 (2013).</li><li>Robinson, J. R., Newcomb, P. A., Hardikar, S., Cohen, S. A., Phipps, A. 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P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recurrence+and+survival+following+microwave,+radiofrequency+ablation,+and+hepatic+resection+of+colorectal+liver+metastases:+A+systematic+review+and+network+meta-analysis.">Recurrence and survival following microwave, radiofrequency ablation, and hepatic resection of colorectal liver metastases: A systematic review and network meta-analysis.</a> Hepatobiliary &amp; Pancreatic Diseases International. 20 (4), 307-314 (2021).</li><li>McEachron, K. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surgical+microwave+ablation+of+otherwise+non-resectable+colorectal+cancer+liver+metastases:+Expanding+opportunities+for+long+term+survival.">Surgical microwave ablation of otherwise non-resectable colorectal cancer liver metastases: Expanding opportunities for long term survival.</a> Surgical Oncology. 36, 61-64 (2021).</li><li>Qin, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+local+efficacy+and+influencing+factors+of+ultrasound-guided+percutaneous+microwave+ablation+in+colorectal+liver+metastases:+A+review+of+a+4-year+experience+at+a+single+center.">The local efficacy and influencing factors of ultrasound-guided percutaneous microwave ablation in colorectal liver metastases: A review of a 4-year experience at a single center.</a> International Journal of Hyperthermia. 36 (1), 36-43 (2019).</li><li>Abreu de Carvalho, L. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Local+control+of+hepatocellular+carcinoma+and+colorectal+liver+metastases+after+surgical+microwave+ablation+without+concomitant+hepatectomy.">Local control of hepatocellular carcinoma and colorectal liver metastases after surgical microwave ablation without concomitant hepatectomy.</a> Langenbeck's Archives of Surgery. 406 (8), 2749-2757 (2021).</li><li>Akgul, O., Cetinkaya, E., Ersoz, S., Tez, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+surgery+in+colorectal+cancer+liver+metastases.">Role of surgery in colorectal cancer liver metastases.</a> World Journal of Gastroenterology. 20 (20), 6113-6122 (2014).</li><li>Francone, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Precoagulation-assisted+parenchyma-sparing+laparoscopic+liver+surgery:+Rationale+and+surgical+technique.">Precoagulation-assisted parenchyma-sparing laparoscopic liver surgery: Rationale and surgical technique.</a> Surgical Endoscopy. 31 (3), 1354-1360 (2017).</li><li>Fahy, B. N., Jarnagin, W. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evolving+techniques+in+the+treatment+of+liver+colorectal+metastases:+Role+of+laparoscopy,+radiofrequency+ablation,+microwave+coagulation,+hepatic+arterial+chemotherapy,+indications+and+contraindications+for+resection,+role+of+transplantation,+and+timing+of+chemotherapy.">Evolving techniques in the treatment of liver colorectal metastases: Role of laparoscopy, radiofrequency ablation, microwave coagulation, hepatic arterial chemotherapy, indications and contraindications for resection, role of transplantation, and timing of chemotherapy.</a> The Surgical Clinics of North America. 86 (4), 1005-1022 (2006).</li><li>Wada, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficacy+of+surgical+treatment+using+microwave+coagulo-necrotic+therapy+for+unresectable+multiple+colorectal+liver+metastases.">Efficacy of surgical treatment using microwave coagulo-necrotic therapy for unresectable multiple colorectal liver metastases.</a> OncoTargets and Therapy. 9, 937-943 (2016).</li><li>Lorentzen, T., Skjoldbye, B. 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The authors have no conflicts of interest to disclose.

The main metastatic site of colorectal cancer metastasis is the liver. Liver resection is the treatment for colorectal cancer liver metastases, and liver resection can improve the survival rate of patients11. As colorectal cancer metastasizes to the liver through the blood, resulting in multiple liver metastases in both lobes, and the remaining liver volume is small, about 75% of liver metastases in colorectal cancer patients cannot be surgically removed12. Systemic chemoth...

Colorectal cancer is the third most common cause of cancer-related death worldwide1, and the most common site of hematogenous metastases from colorectal cancer is the liver; this metastasis occurs in up to 50% of colorectal patients and is the leading cause of death in colorectal cancer patients2. For colorectal cancer patients without liver metastases, survival can be prolonged by surgical resection and&#160;postoperative adjuvant chemotherapy, and interventional techniques. In the case of resectable liver metastases, those with a diameter of less than 3 cm can be treated by surgical local excision, radiological intervention, cryotherapy, radiofrequency ablation, and microwave ablation to improve the survival rate of patients3. For unresectable colorectal cancer liver metastases, conventional chemotherapy, interventional therapy, and other treatment strategies have limited survival benefits for the vast majority of patients.
Surgery is the gold standard for liver metastases from colorectal cancer, with a 5 year survival rate of 40%. Only 20%-30% of patients with colorectal liver metastases can benefit from surgical treatment, and most patients with unresectable colorectal liver metastases experience limited benefit from traditional conservative treatment4. An important method in the treatment of colorectal cancer liver metastases is thermal ablation, including microwave ablation and radiofrequency ablation; these two techniques induce cell death through coagulation necrosis caused by local hyperthermia. The main indications of thermal ablation include (i) unresectable liver lesions; (ii) combination with hepatectomy; (iii) patients with severe comorbidities or poor performance status (PS); (iv) small (&#60;3 cm) solitary lesions otherwise requiring segmentectomy; and (v) patient preference5. Among them, microwave ablation (MWA) is a safe and effective treatment that can prolong the survival of patients. It has a wide range of active heating areas and does not depend on electrical conduction in the tumor tissue. This energy transfer is not limited by tissue scorching. Compared with radiofrequency ablation, microwave ablation has a higher temperature in the tumor tissue, shorter treatment time, and larger treatment range6.
Multiple intrahepatic metastases often occur in colorectal cancer liver metastases. In conventional treatment, chemotherapy, immunotherapy, interventional therapy, microwave therapy, radiofrequency ablation, and other methods can improve the survival rate of patients. The 5 year survival rate is 50%, but the survival rate is still low7. Surgical resection is still an important method for the treatment of liver metastases. Due to multiple liver metastases, small residual liver volume, postoperative bleeding, bile leakage, and inflow or outflow tract obstruction, which lead to the risk of liver failure, the surgical resection of multiple liver metastases is difficult. Three-quarters of patients are diagnosed with unresectable liver metastases8. Laparoscopic hepatectomy combined with microwave ablation in the treatment of colorectal cancer liver metastases can avoid the small amount of residual liver limiting the operation, reduce the adverse reactions of systemic chemotherapy, and overcome the electrical conduction barrier of radiofrequency ablation, thereby improving the success rate of surgery, prolonging the survival time of patients, and achieving a better prognosis of colorectal cancer liver metastases3,9.
This protocol describes the precision treatment of laparoscopic hepatectomy combined with microwave ablation for tumors &#60;3 cm, occult liver metastases, and multiple liver metastases with positioning using laparoscopic ultrasound.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.9% sodium chloride solution</td>
			<td>Foshan Shuanghe Commercial Co., Ltd</td>
			<td>H20013095</td>
			<td>Dilute antibiotics, irrigate.</td>
		</tr>
		<tr>
			<td>2-0 polyglactin 910 sutures</td>
			<td>Johnson &#38; Johnson Medical Devices</td>
			<td>W8400</td>
			<td>Close the Trocar hole.</td>
		</tr>
		<tr>
			<td>3 D laparoscopic</td>
			<td>STORZ</td>
			<td>26605BA</td>
			<td>Surgical treatment under direct vision, minimally invasive</td>
		</tr>
		<tr>
			<td>Absorbable Hemostat</td>
			<td>ETHICON</td>
			<td>1962</td>
			<td>wound hemostasis</td>
		</tr>
		<tr>
			<td>BiClamp E Lap</td>
			<td>ERBE Elektromedizin GmbH</td>
			<td>20195-136</td>
			<td>Intraoperative wound hemostasis</td>
		</tr>
		<tr>
			<td>Cefoperazone Sulbactam Sodium</td>
			<td>Pfizer Pharmaceuticals Ltd</td>
			<td>H20020597</td>
			<td>infection prevention</td>
		</tr>
		<tr>
			<td>Laparoscopic ultrasound probe</td>
			<td>HITACHI</td>
			<td>ALOKA-UST5418</td>
			<td>Intraoperative localization of liver metastases</td>
		</tr>
		<tr>
			<td>LIGACLIP Multiple Clip Applier and Ligating Clips</td>
			<td>Ethicon Endo - Surgery, LLC</td>
			<td>ER320</td>
			<td>Clamp tiny blood vessels and bile ducts</td>
		</tr>
		<tr>
			<td>Microwave ablation System</td>
			<td>Nanjing Yigao Microwave System Engineering Co., Ltd, China</td>
			<td>ECO-100A110</td>
			<td>Microwave ablation of liver metastases</td>
		</tr>
		<tr>
			<td>Polymer ligation clips</td>
			<td>Teleflex Medical, USA</td>
			<td>Hem-lock544233</td>
			<td>Clipping of broken ends of blood vessels and bile ducts</td>
		</tr>
		<tr>
			<td>Silica gel drainage tube</td>
			<td>BAINUS MEDICAL</td>
			<td>YY-Fr16</td>
			<td>Drainage of peritoneal fluid</td>
		</tr>
		<tr>
			<td>Ultrasonic knife</td>
			<td>Johnson &#38; Johnson Medical Devices</td>
			<td>HAR36</td>
			<td>Tissue cutting, microvascular hemostasis</td>
		</tr>
	</tbody>
</table>

application of laparoscopic hepatectomy combined with intraoperative microwave ablation in colorectal cancer liver metastasis

Laparoscopic hepatectomy is a common treatment for colorectal cancer liver metastasis. Previously, a sufficient number of functional liver masses had to be maintained during laparoscopic hepatectomy, with a residual liver volume of &gt;40% in cirrhotic patients and &gt;30% in non-cirrhotic patients. The high incidence of complications such as bleeding, bile leakage, or liver failure due to the exposure and difficulty of the resection of specific liver segments such as S2 and S7 reduces the success rate of liver resection. At present, microwave ablation is mainly applied in the treatment of liver metastasis using a percutaneous approach, which makes it difficult to identify hidden parts or small lesions. For some liver segments, the percutaneous puncture of liver segment 7 (S7) is likely to pass through the thoracic cavity, and the percutaneous puncture of liver segment 2 (S2) adjacent to the diaphragm is likely to injure the diaphragm and heart; these issues restrict the application of percutaneous ablation in colorectal cancer liver metastasis. Considering multiple lesions, laparoscopic microwave ablation combined with hepatectomy was performed in this study. The location of the lesions was determined by contrast-enhanced ultrasound under laparoscopy, and small lesions that were difficult to detect before the operation were identified. For the scattered lesions, which had diameters less than 3 cm and were difficult to resect, ablation was adopted to substitute hepatectomy. This technique helped to more explicitly locate the tumors, simplified the operation procedures, reduced the risk of complications such as bleeding and bile leakage, shortened the operation time, accelerated the postoperative recovery, significantly improved the success rate of operation, and enhanced the clinical prognosis of colorectal cancer liver metastasis by surgical resection.

For patients with liver metastases from past colorectal cancer, patients with unilateral liver metastases, or patients with few liver metastases can undergo surgical resection and obtain a good prognosis. Nevertheless, in patients with unresectable colorectal cancer with multiple liver metastases in both lobes, conservative treatment has a poor prognosis and a low 5 year survival rate. However, hepatectomy combined with microwave ablation can further improve the survival rate of patients and achieve a good prognosis comp...

Watch this Scientific Journal Video about Application of Laparoscopic Hepatectomy Combined with Intraoperative Microwave Ablation in Colorectal Cancer Liver Metastasis at JoVE.com

Application of Laparoscopic Hepatectomy Combined with Intraoperative Microwave Ablation in Colorectal Cancer Liver Metastasis

This protocol describes the laparoscopic resection of colorectal cancer liver metastases combined with ultrasound-guided microwave ablation. This technique can safely, effectively, and accurately treat refractory liver metastases &lt;3 cm, reduce postoperative complications, and accelerate the postoperative rehabilitation of patients.

Laparoscopic hepatectomy is a common treatment for colorectal cancer liver metastasis. Previously, a sufficient number of functional liver masses had to ...

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312 Views.  Sun Yat-sen University. This protocol describes the laparoscopic resection of colorectal cancer liver metastases combined with ultrasound-guided microwave ablation. This technique can safely, effectively, and accurately treat refractory liver metastases 

Video: Application of Laparoscopic Hepatectomy Combined with Intraoperative Microwave Ablation in Colorectal Cancer Liver Metastasis

Intraoperative Gastroscopy for Tumor Localization in Laparoscopic Surgery for Gastric Adenocarcinoma

Determining resection margins for gastric cancer, which are not exposed to the serosal surface of the stomach, is the most important procedure during totally laparoscopic gastrectomy (TLG). The aim of this protocol is to introduce a procedure for intraoperative gastroscopy, in order to directly mark tumors during TLG for gastric cancer in the middle third of the stomach. Patients who were diagnosed with adenocarcinoma in the middle third of the stomach were enrolled in this case series. Before surgery, additional gastroscopy for tumor localization is not performed. Under general anesthesia, laparoscopic mobilization of the stomach is performed first. After the first portion of the duodenum is mobilized from the pancreas and clamped, the surgeon moves to the other side for the gastroscopic procedure. On the insertion of a gastroscope through the oral cavity into the stomach, 2 - 3 cc of indigo carmine is administered via an endoscopic injector into the gastric muscle layer at the proximal margin of the stomach. The location of stained serosa in the laparoscopic view is used to guide distal subtotal gastrectomy, however, total gastrectomy is performed if the tumor is too close to the esophagogastric junction. A specimen is sampled after distal gastrectomy to confirm sufficient length from resection margin to tumor before reconstruction. In our case series, all patients had tumor-free margins and required no additional resection. There was no morbidity related to the gastroscopic procedure, and the time required for the procedure has gradually decreased to about five minutes. Intraoperative gastroscopy for tumor localization is an accurate and tolerated method for gastric cancer patients undergoing totally laparoscopic distal gastrectomy.

In early gastric cancer, the aim of surgery is to precisely remove the distal stomach including the primary tumor. To do this, accurate localization of the tumor is crucial, especially in totally laparoscopic surgery. This protocol describes a procedure for intraoperative gastroscopy in totally laparoscopic subtotal gastrectomy.

Determining resection margins for gastric cancer, which are not exposed to the serosal surface of the stomach, is the most important procedure during ...

Quantitation of Intra-peritoneal Ovarian Cancer Metastasis

Epithelial ovarian cancer (EOC) is the leading cause of death from gynecologic malignancy in the United States. Mortality is due to diagnosis of 75% of women with late stage disease, when metastasis is already present. EOC is characterized by diffuse and widely disseminated intra-peritoneal metastasis. Cells shed from the primary tumor anchor in the mesothelium that lines the peritoneal cavity as well as in the omentum, resulting in multi-focal metastasis, often in the presence of peritoneal ascites. Efforts in our laboratory are directed at a more detailed understanding of factors that regulate EOC metastatic success. However, quantifying metastatic tumor burden represents a significant technical challenge due to the large number, small size and broad distribution of lesions throughout the peritoneum. Herein we describe a method for analysis of EOC metastasis using cells labeled with red fluorescent protein (RFP) coupled with in vivo multispectral imaging. Following intra-peritoneal injection of RFP-labelled tumor cells, mice are imaged weekly until time of sacrifice. At this time, the peritoneal cavity is surgically exposed and organs are imaged in situ. Dissected organs are then placed on a labeled transparent template and imaged ex vivo. Removal of tissue auto-fluorescence during image processing using multispectral unmixing enables accurate quantitation of relative tumor burden. This method has utility in a variety of applications including therapeutic studies to evaluate compounds that may inhibit metastasis and thereby improve overall survival.

Ovarian cancer metastasis is characterized by numerous diffuse intra-peritoneal lesions, such that accurate visual quantitation of tumor burden is challenging. Herein we describe a method for in situ and ex vivo quantitation of metastatic tumor burden using red fluorescent protein (RFP)-labeled tumor cells and optical imaging.

Epithelial ovarian cancer (EOC) is the leading cause of death from gynecologic malignancy in the United States.  Mortality is due to diagnosis of 75% of ...

Laparoscopic Technique for Serial Collection of Liver and Mesenteric Lymph Nodes in Macaques

The mesenteric lymph nodes (MLN) and the liver are exposed to microbes and microbial products from the gastrointestinal (GI) tract, making them immunologically unique. The GI tract and associated MLN are sites of early viral replication in human immunodeficiency virus (HIV) infection and the MLN are likely important reservoir sites that harbor latently-infected cells even after prolonged antiretroviral therapy (ART). The liver has been shown to play a significant role in immune responses to lentiviruses and appears to play a significant role in clearance of virus from circulation. Nonhuman primate (NHP) models for HIV and Acquired Immunodeficiency Syndrome (AIDS) closely mimic these aspects of HIV infection and serial longitudinal sampling of primary sites of viral replication and the associated immune responses in this model will help to elucidate critical events in infection, pathogenesis, and the impact of various intervention strategies on these events. Current published techniques to sample liver and MLN together involve major surgery and/or necropsy, which limits the ability to investigate these important sites in a serial fashion in the same animal. We have previously described a laparoscopic technique for collection of MLN. Here, we describe a minimally invasive laparoscopic technique for serial longitudinal sampling of liver and MLN through the same two port locations required for the collection of MLN. The use of the same two ports minimizes the impact to the animals as no additional incisions are required. This technique can be used with increased sampling frequency compared to major abdominal surgery and reduces the potential for surgical complications and associated local and systemic inflammatory responses that could complicate interpretation of results. This procedure has potential to facilitate studies involving NHP models while improving animal welfare.

Here, we describe a minimally invasive laparoscopic technique for serial sampling of liver and mesenteric lymph nodes (MLN) in macaques that allows for increased sampling frequency, and reduces the potential for surgical complications when compared to performing a laparotomy.

The mesenteric lymph nodes (MLN) and the liver are exposed to microbes and microbial products from the gastrointestinal (GI) tract, making them ...

Re-Arterialized Rat Partial Liver Transplantation with an in vivo Vessel-Oriented 70% Hepatectomy

Split liver transplantation and living liver donor liver transplantation were developed in the clinic to utilize liver organs in a more efficient manner. To better understand the mechanism behind these surgical procedures, a rat partial liver transplantation (PLTx) model was established for relevant surgical studies. Because of the complexity of the rat PLTx model, a protocol with detailed descriptions is required. An article published previously reported a protocol in which ex vivo hepatectomy was used to achieve 50% rat PLTx. In contrast to this protocol, we introduced a re-arterialized PLTx with an in vivo 70% hepatectomy. An updated vessel-oriented hepatectomy was incorporated into the rat PLTx to refine the microsurgical procedure. The portal veins and hepatic arteries of the left lateral lobe and the median lobe were individually dissected and ligated before removal of the liver parenchyma, thereby decreasing the probability of bleeding in the remnant liver stump. Furthermore, an end-to-side vessel anastomosis between the common hepatic artery and the enlarged proper hepatic artery was introduced to re-arterialize the hepatic artery. By using this end-to-side vessel anastomosis technique, the diameter of the anastomosis was enlarged, thereby decreasing the difficulty of hand suture and maintaining a high rate of anastomotic patency. Moreover, the cuff anastomosis of the infrahepatic vena cava was slightly modified. A section of circumferential liver parenchyma around the vena cava of a recipient was preserved during cuff anastomosis to maintain the three-dimensional shape of the vascular lumen. This section of liver parenchyma was removed after completing the anastomosis. With this modification, the step involving placement of stay sutures was omitted, thereby further shortening the cuff anastomosis time. By using this protocol of rat PLTx, a low liver enzyme level, an intact liver lobular architecture and a high survival rate were achieved after microsurgery.

Re-Arterialized Rat Partial Liver Transplantation with an in vivo Vessel-Oriented 70% Hepatectomy

Here, a protocol involving re-arterialized rat partial liver transplantation is presented. Specifically, 70% liver was resected in vivo by using an updated technique of vessel-oriented hepatectomy. The hepatic artery was reconstructed in an end-to-side manner. The cuff technique was modified to shorten the anastomosis time of the infrahepatic vena cava.

Split liver transplantation and living liver donor liver transplantation were developed in the clinic to utilize liver organs in a more efficient manner. ...

Intraoperative Assessment of Resection Margins in Oral Cavity Cancer: This is the Way

The goal of head and neck oncological surgery is complete tumor resection with adequate resection margins while preserving acceptable function and appearance. For oral cavity squamous cell carcinoma (OCSCC), different studies showed that only 15%-26% of all resections are adequate. A major reason for the low number of adequate resections is the lack of information during surgery; the margin status is only available after the final histopathologic assessment, days after surgery.
The surgeons and pathologists at the Erasmus MC University Medical Center in Rotterdam started the implementation of specimen-driven intraoperative assessment of resection margins (IOARM) in 2013, which became the standard of care in 2015. This method enables the surgeon to turn an inadequate resection into an adequate resection by performing an additional resection during the initial surgery. Intraoperative assessment is supported by a relocation method procedure that allows accurate identification of inadequate margins (found on the specimen) in the wound bed.
The implementation of this protocol resulted in an improvement of adequate resections from 15%-40%. However, the specimen-driven IOARM is not widely adopted because grossing fresh tissue is counter-intuitive for pathologists. The fear exists that grossing fresh tissue will deteriorate the anatomical orientation, shape, and size of the specimen and therefore will affect the final histopathologic assessment. These possible negative effects are countered by the described protocol. Here, the protocol for specimen-driven IOARM is presented in detail, as performed at the institute.

The goal of this protocol is to provide a clear overview of specimen-driven intraoperative assessment of resection margins. It is encouraged to implement this protocol to improve patient care at other institutes.

The goal of head and neck oncological surgery is complete tumor resection with adequate resection margins while preserving acceptable function and ...

Establishment of a Simple and Effective Rat Model for Intraoperative Parathyroid Gland Imaging

Parathyroid gland (PG) identification is a critical unmet need in thyroidectomy. The identification of the PG is challenging in thyroid surgery as it is similar in color to the thyroid gland. The lack of effective animal models in preclinical research is a severe limitation for the development of PG identification techniques. This protocol allows for the establishment of a simple and effective rat model for PG identification. In this model, black iron oxide nanoparticles (IONPs) are injected locally in the thyroid gland and rapidly diffuse within the thyroid gland but not the PG. A negatively stained PG and a positively stained thyroid gland can be easily identified by the naked eye without requiring external microscopes. The position of the PG can be identified by increasing the color contrast between the thyroid gland and the PG, based on the color of the black IONPs. This rat model is low-cost and convenient for PG identification, and the IONPs are a novel PG contrast agent.

To date, the development of parathyroid gland (PG) identification methods is limited by the lack of animal models in preclinical research. Here, we establish a simple and effective rat model for intraoperative PG imaging and evaluate its effectiveness by using iron oxide nanoparticles as a novel PG contrast agent.

Parathyroid gland (PG) identification is a critical unmet need in thyroidectomy. The identification of the PG is challenging in thyroid surgery as it is ...

Application of a New Mesh Fixation Method in Laparoscopic Incisional Hernia Repair

Laparoscopic incisional hernia repair using intraperitoneal onlay mesh (IPOM) is one of the most widely used minimally invasive methods for repairing incisional hernias. The laparoscopic IPOM involves implanting the mesh into the abdominal cavity through laparoscopy to repair an abdominal wall hernia. In the IPOM surgery, after the closure of the hernia ring, an anti-adhesion mesh is placed laparoscopically. The correct placement of this mesh is critical to the success of the method, and surgical skills are required to achieve perfect placement. If the mesh placement is not mastered properly, the operation and anesthesia time will be prolonged. In addition, improper placement of the mesh can lead to serious consequences, such as intestinal obstruction and mesh infection. A "contraposition and alignment" mesh fixation method is described in this study, which involves pre-marking the fixation position of the mesh to reduce the difficulty of mesh placement. A properly placed mesh is completely flat on the peritoneum, the edges are not curled or wrapped, and the mesh is adhered firmly such that there is no displacement after removing the pneumoperitoneum pressure. The "contraposition and alignment" mesh fixation technique offers the advantages of reliable placement of the mesh and fewer complications than other techniques, and it is easy to learn and master. It also allows for positioning the nail gun in advance based on the anatomy of the incisional hernia. This enables the use of the minimum number of nails possible while still ensuring good fixation, which can reduce the occurrence of complications and reduce the cost of surgery. Thus, the mesh fixation method described here is highly suitable for clinical applications based on the aforementioned advantages.

Presented here is a method for improving the mesh placement in laparoscopic incisional hernia repair, which can shorten the time required for mesh fixation and reduce the occurrence of postoperative chronic pain.

Laparoscopic incisional hernia repair using intraperitoneal onlay mesh (IPOM) is one of the most widely used minimally invasive methods for repairing ...

Fluorescent Laparoscopic Central Hepatectomy for Liver Cancer Using Indocyanine Green Negative Staining

Laparoscopic hepatectomy is an important treatment method for liver cancer. In the past, the resection boundary was usually determined by intraoperative ultrasound, important vascular structures, and surgeon experience. With the development of anatomical hepatectomy, visual surgery technology has gradually been applied to this type of surgery, particularly indocyanine green (ICG)-guided anatomical hepatectomy. As ICG can be specifically ingested by hepatocytes and used for fluorescence tracing, negative staining techniques have been applied according to different tumor positions. Under ICG fluorescent guidance, the surface boundary and deep resection plane can be more accurately displayed during liver resection. Thus, the tumor-bearing liver segment can be anatomically removed, which helps to avoid damage to important vessels and reduce ischemia or congestion of the remaining liver tissue. Finally, the incidence of postoperative biliary fistula and liver dysfunction is reduced; therefore, a better prognosis is obtained after the resection of liver cancer. Centrally located liver cancer is usually defined as a tumor located at segments 4, 5, or 8 that requires resection of the middle section of the liver. These are among the most difficult hepatectomies to perform because of the large surgical wounds and multiple vessel transections. Based on the specific tumor location, we formulated the required resection ranges by designing personalized fluorescent staining strategies. By completing anatomical resection based on the portal territory, this work aims to achieve the best therapeutic effect.

The present protocol describes fluorescent negative staining in laparoscopic central hepatectomy. This technique can make hepatectomy more accurate and precise.

Laparoscopic hepatectomy is an important treatment method for liver cancer. In the past, the resection boundary was usually determined by intraoperative ...

Clinical Application of Single-Surgeon, Three-Port, Laparoscopic Resection for Colorectal Cancer with Natural Orifice Specimen Extraction

Reduced-port laparoscopic surgery (RPLS) has been widely used for the radical resection of gastrointestinal tumors. Single-surgeon, three-port, laparoscopic radical resection for sigmoid colon or high rectal cancer with natural orifice specimen extraction surgery (NOSES) has the advantage of a small incision, quick postoperative recovery, and short hospital stay. Yet, there are still only a few reports on NOSES. This paper describes the indications, preoperative preparations, surgical steps, and precautions for single-surgeon, three-port, laparoscopic radical resection of the sigmoid colon and high rectal cancer, and intraoperative specimen collection through the natural orifice. 
The protocol focuses on the steps of radical dissection and the main technical points of resection and reconstruction. At the same time, a procedure for fixing an anvil seat by self-traction of extracorporeal silk thread, used for purse-string suture fixation after the proximal anvil was placed in the abdominal cavity, was creatively improved. This operation could effectively avoid problems such as an insufficient proximal intestinal tube, shaking off the anvil seat, and weak purse-string suture during a single operation. The surgical care had less variability and was easy to perform, effectively avoiding postoperative anastomotic leakage and bleeding due to excessive intraoperative anastomotic tissue. This surgery could be widely promoted in primary hospitals.

Here, we present a protocol to successfully perform single-surgeon, three-port, laparoscopic resection for colorectal cancer with natural orifice specimen extraction.

Reduced-port laparoscopic surgery (RPLS) has been widely used for the radical resection of gastrointestinal tumors. Single-surgeon, three-port, ...

Modified Laparoscopic Anatomic Hepatectomy: Two-Surgeon Technique Combined with the Simple Extracorporeal Pringle Maneuver

Laparoscopic anatomic hepatectomy (LAH) has become increasingly prevalent worldwide in recent years. However, LAH remains a challenging procedure due to the anatomical characteristics of the liver, with intraoperative hemorrhage being a primary concern. Intraoperative blood loss is the leading cause of conversion to open surgery; therefore, effective management of bleeding and hemostasis is crucial for a successful LAH.
The two-surgeon technique is proposed as an alternative to the traditional single-surgeon approach, with potential benefits in reducing intraoperative bleeding during laparoscopic hepatectomy. However, there remains a lack of evidence to determine which mode of the two-surgeon technique yields superior patient outcomes. Besides, to our knowledge, the LAH technique, which involves the use of a cavitron ultrasonic surgical aspirator (CUSA) by the primary surgeon while an ultrasonic dissector by the second surgeon, has been rarely reported before.
Herein, we present a modified, two-surgeon LAH technique, wherein one surgeon employs a CUSA while the other uses an ultrasonic dissector. This technique is combined with a simple extracorporeal Pringle maneuver and low central venous pressure (CVP) approach. In this modified technique, the primary and secondary surgeons utilize a laparoscopic CUSA and an ultrasonic dissectorconcurrently to achieve precise and expeditious hepatectomy. A simple extracorporeal Pringle maneuver, combined with the maintenance of low CVP, is employed to regulate the hepatic inflow and outflow in order to minimize intraoperative bleeding. This approach facilitates the attainment of a dry and clean operative field, which allows for the precise ligation and dissection of blood vessels and bile ducts. The modified LAH procedure is simpler and safer due to its effective control over bleeding as well as the seamless transition between the roles of primary and secondary surgeons. It holds great promise for future clinical applications.

Here, we present a protocol to perform a modified laparoscopic anatomic hepatectomy using improved techniques and instruments.

Laparoscopic anatomic hepatectomy (LAH) has become increasingly prevalent worldwide in recent years. However, LAH remains a challenging procedure due to ...