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>
	<li>Shi, 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=Long-term+results+of+percutaneous+microwave+ablation+for+colorectal+liver+metastases.">Long-term results of percutaneous microwave ablation for colorectal liver metastases.</a> HPB. 23 (1), 37-45 (2021).</li><li>Xu, J., 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=Chinese+guidelines+for+the+diagnosis+and+comprehensive+treatment+of+colorectal+liver+metastases+(version+2018).">Chinese guidelines for the diagnosis and comprehensive treatment of colorectal liver metastases (version 2018).</a> Journal of Cancer Research and Clinical Oncology. 145 (3), 725-736 (2019).</li><li>Schnitzbauer, A., Bechstein, W. 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. 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=Cytoreduction+for+colorectal+metastases:+liver,+lung,+peritoneum,+lymph+nodes,+bone,+brain.+When+does+it+palliate,+prolong+survival,+and+potentially+cure.">Cytoreduction for colorectal metastases: liver, lung, peritoneum, lymph nodes, bone, brain. 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. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stage+IV+colorectal+cancer+primary+site+and+patterns+of+distant+metastasis.">Stage IV colorectal cancer primary site and patterns of distant metastasis.</a> Cancer Epidemiology. 48, 92-95 (2017).</li><li>Gavriilidis, P., Roberts, K. J., de'Angelis, N., Aldrighetti, L., Sutcliffe, R. 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. O., Nolsoe, C. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microwave+ablation+of+liver+metastases+guided+by+contrast-enhanced+ultrasound:+Experience+with+125+metastases+in+39+patients.">Microwave ablation of liver metastases guided by contrast-enhanced ultrasound: Experience with 125 metastases in 39 patients.</a> Ultraschall in der Medizin. 32 (5), 492-496 (2011).</li></ol>

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><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 &amp;amp; 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 &amp;amp; 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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321 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

Thermal Ablation for the Treatment of Abdominal Tumors

Percutaneous thermal ablation is an emerging treatment option for many tumors of the abdomen not amenable to conventional treatments. During a thermal ablation procedure, a thin applicator is guided into the target tumor under imaging guidance. Energy is then applied to the tissue until temperatures rise to cytotoxic levels (50-60 &deg;C). Various energy sources are available to heat biological tissues, including radiofrequency (RF) electrical current, microwaves, laser light and ultrasonic waves. Of these, RF and microwave ablation are most commonly used worldwide.
During RF ablation, alternating electrical current (~500 kHz) produces resistive heating around the interstitial electrode. Skin surface electrodes (ground pads) are used to complete the electrical circuit. RF ablation has been in use for nearly 20 years, with good results for local tumor control, extended survival and low complication rates1,2. Recent studies suggest RF ablation may be a first-line treatment option for small hepatocellular carcinoma and renal-cell carcinoma3-5. However, RF heating is hampered by local blood flow and high electrical impedance tissues (eg, lung, bone, desiccated or charred tissue)6,7. Microwaves may alleviate some of these problems by producing faster, volumetric heating8-10. To create larger or conformal ablations, multiple microwave antennas can be used simultaneously while RF electrodes require sequential operation, which limits their efficiency. Early experiences with microwave systems suggest efficacy and safety similar to, or better than RF devices11-13.
Alternatively, cryoablation freezes the target tissues to lethal levels (-20 to -40 &deg;C). Percutaneous cryoablation has been shown to be effective against RCC and many metastatic tumors, particularly colorectal cancer, in the liver14-16. Cryoablation may also be associated with less post-procedure pain and faster recovery for some indications17. Cryoablation is often contraindicated for primary liver cancer due to underlying coagulopathy and associated bleeding risks frequently seen in cirrhotic patients. In addition, sudden release of tumor cellular contents when the frozen tissue thaws can lead to a potentially serious condition known as cryoshock 16.
Thermal tumor ablation can be performed at open surgery, laparoscopy or using a percutaneous approach. When performed percutaneously, the ablation procedure relies on imaging for diagnosis, planning, applicator guidance, treatment monitoring and follow-up. Ultrasound is the most popular modality for guidance and treatment monitoring worldwide, but computed tomography (CT) and magnetic resonance imaging (MRI) are commonly used as well. Contrast-enhanced CT or MRI are typically employed for diagnosis and follow-up imaging.

A thermal tumor ablation procedure is described. The entire procedure is detailed, including pretreatment planning and imaging studies, anesthesia, adjuvant techniques to facilitate a percutaneous approach, imaging guidance of the ablation device to the tumor, thermal treatment, post-treatment care and follow-up.

Percutaneous thermal ablation is an emerging treatment option for many tumors of the abdomen not amenable to conventional treatments. During a thermal ...

Evaluation of the Feasibility, Safety, and Accuracy of an Intraoperative High-intensity Focused Ultrasound Device for Treating Liver Metastases

Today, the only potentially curative option in patients with colorectal liver metastases is surgery. However, liver resection is feasible in less than 20% of patients. Surgery has been widely used in association with radiofrequency, cryotherapy, or microwaves to expand the number of treatments performed with a curative intent. Nevertheless, several limitations have been documented when using these techniques (i.e., a traumatic puncture of the parenchyma, a limited size of lesions, and an inability to monitor the treatment in real-time).High-intensity focused ultrasound (HIFU) technology can achieve precise ablations of biological tissues without incisions or radiation. Current HIFU devices are based on an extracorporeal approach with limited access to the liver. We have developed a HIFU device designed for intraoperative use. The use of a toroidal transducer enables an ablation rate (10 cm3&#183;min-1) higher than any other treatment and is independent of perfusion.
The feasibility, safety, and accuracy of intraoperative HIFU ablation were evaluated during an ablate-and-resect prospective study. This clinical phase I and IIa study was performed in patients undergoing hepatectomy for liver metastases. The HIFU treatment was performed on healthy tissue scheduled for resection.Liver metastases measuring less than 20 mm will be targeted during phase IIb (currently ongoing). This set-up allows the real-time evaluation of HIFU ablation while protecting participating patients from any adverse effects related to this new technique.
Fifteen patients were included in phase I&#8211;IIa and 30 HIFU ablations were safely created within 40 s and with a precision of 1&#8211;2 mm. The average dimensions of the HIFU ablations were 27.5 x 21.0 mm2, corresponding to a volume of approximately 7.5 cm3. The aim of the ongoing phase IIb is to ablate metastases of less than 20 mm in diameter with a 5 mm margin.

Here, we present an ablate-and-resect prospective study to evaluate the feasibility, safety, and accuracy of intraoperative high-intensity focused ultrasound ablation in patients undergoing hepatectomy for liver metastases.

Today, the only potentially curative option in patients with colorectal liver metastases is surgery. However, liver resection is feasible in less than 20% ...

Cancer Research

Application of Hemostatic Devices in Laparoscopic Hepatectomy

Laparoscopic hepatectomy is considered a conventional method for treating benign and malignant liver diseases because it is a minimally invasive method. Despite its non-invasive aspect, bleeding and bile leakage occur in liver parenchyma tissue resection during the operation or in the post-operation period, indicating the requirement for high-grade hemostatic devices, such as ultrasonic surgical aspiration, bipolar electrocoagulation, etc. The lack of availability of these high-grade hemostatic devices prevents laparoscopic hepatectomy from becoming a generalized procedure in basic medical organizations. In view of the situation mentioned above, a suite of simple and easy hemostatic devices is developed in this protocol, which includes a harmonic scalpel, monopole electrocoagulation, and a single lumen catheter, to innovatively perform liver parenchyma tissue resection. First of all, the porta hepatis or hepatic pedicle is occluded intermittently by a single lumen catheter, followed by clamping for 15 min and releasing for 5 min. Subsequently, using the harmonic scalpel, clamping and crushing of the liver are done to cut off the hepatic parenchyma tissue and to reveal the intrahepatic arteries, veins, and bile ducts. Lastly, the bleeding spots are coagulated by using monopole electrocoagulation at each spot. Intrahepatic pipeline structures are then visible by using these methods, which could stop bleeding easily, reduce the incidence rate of bile leakage, and improve the safety and feasibility of laparoscopic hepatectomy. Therefore, the simple and easy hemostatic devices shown here are suitable for conducting procedures in primary medical institutions.

High-grade hemostatic devices are essential for laparoscopic hepatectomy. However, these devices are not generalized in basic medical organizations. Therefore, a suite of simple and easy hemostatic devices is shown in this article, which can make the laparoscopic hepatectomy easier to perform.

Laparoscopic hepatectomy is considered a conventional method for treating benign and malignant liver diseases because it is a minimally invasive method. ...

Application of the En Bloc Concept Combined with Anatomic Resection in Laparoscopic Hepatectomy

Laparoscopic hepatectomy has been reported in many studies, and it is the mainstream method of liver resection. In some particular cases, such as when there are tumors adjacent to the cystic bed, surgeons cannot palpate the surgical margins through the laparoscopic approach, which leads to uncertainty about R0 resection. Conventionally, the gallbladder is resected first, and the hepatic lobes or segments are resected second. However, tumor tissues can be disseminated in the above cases. To address this issue, based on the recognition of the porta hepatis and intrahepatic anatomy, we propose a unique approach to hepatectomy combined with gallbladder resection by en bloc anatomic resection in situ. Firstly, after dissecting the cystic duct, without cutting the gallbladder primarily, the porta hepatis is pre-occluded by the single lumen ureter; secondly, the left hepatic pedicle is made free by the gap of the Laennec membrane and Hilar plate; thirdly, the assistant is asked to drag the fundus of the gallbladder, and the liver parenchyma tissue is resected using a harmonic scalpel along the ischemia line on the liver surface and intraoperative ultrasound. The whole middle hepatic vein (MHV) and its tributaries appear completely; lastly, the left hepatic vein (LHV) is disconnected, and the specimen is taken out from the abdominal cavity. The tumor, gallbladder, and other surrounding tissues are resected en bloc, which meets the tumor-free criterion, and a wide incisal margin and R0 resection are achieved. Therefore, the laparoscopic hepatectomy with the combination of the en bloc concept and anatomic resection is a safe, effective, and radical method with low postoperative recurrence and metastasis.

Numerous studies have demonstrated the advantages of anatomic resection. Nonetheless, whether anatomic resection can increase R0 resection rates remains controversial. Consequently, the present study describes an innovative procedure involving the en bloc concept combined with anatomic resection in laparoscopic hepatectomy, which can reduce postoperative recurrence and metastasis.

Laparoscopic hepatectomy has been reported in many studies, and it is the mainstream method of liver resection. In some particular cases, such as when ...

Laparoscopic Anterior Right Hepatectomy: A Single-Center Experience

Laparoscopic anterior right hepatectomy (LARH) has been used in some hospitals. However, data on the feasibility and safety of this procedure are still limited, due to the demanding technical requirements. The primary objective of this study was to compare the clinical outcomes of LARH with those of laparoscopic conventional right hepatectomy (LCRH) in patients with large right hepatocellular carcinoma, as well as to confirm the safety and feasibility of LARH. Furthermore, the article presents a step-by-step description of the surgical procedures for LARH to help perform this surgery in the clinic. The principle of LARH is to first prioritize the hepatic inlet duct separation while separating the right hepatic perihepatic ligament after transecting the liver. From December 2015 to June 2022, 82 patients with large right hepatocellular carcinoma (maximum tumor diameter &#8805; 5 cm), were recruited for the study. In this cohort, 54 and 28 patients underwent LARH and LCRH, respectively. The perioperative clinical data and survival outcomes of the two groups were compared. Compared with LCRH, LARH exhibited the advantages of less contact and extrusion, thereby leading to the achievement of superior results. Thus, we propose that LARH is the optimal choice for patients with large right hepatocellular carcinoma.

Here we present a step-by-step protocol for conducting laparoscopic anterior right hepatectomy and compare its clinical effects and postoperative outcomes with those of conventional hepatectomies. Analysis of the data of 82 patients with hepatocellular carcinoma revealed that laparoscopic anterior right hepatectomy had better clinical outcomes and survival rates than the conventional hepatectomy.

Laparoscopic anterior right hepatectomy (LARH) has been used in some hospitals. However, data on the feasibility and safety of this procedure are still ...

Behavior

Treatment of Liver Metastases Using an Internal Target Volume Method for Stereotactic Body Radiotherapy

The prognosis of patients with metastatic cancers has improved in the past decades due to effective chemotherapy and oligometastatic surgery. For inoperable patients, local ablation therapies, such as stereotactic body radiotherapy (SBRT), can provide effective local tumor control with minimal toxicity. Because of its high precision and accuracy, SBRT delivers a higher radiation dose per fraction, is more effective, and targets smaller irradiation volumes than does conventional radiotherapy. In addition, steep dose gradients from target lesions to surrounding normal tissues are achieved using SBRT; thus, SBRT provides more effective tumor control and exhibits fewer side effects than conventional radiotherapy. The use of SBRT is prevalent for treating intracranial lesions (known as stereotactic radiosurgery); however, it is now also used for treating spinal and adrenal metastases. Because of advancements in image-guided assistance and respiratory motion management, several studies have investigated the use of SBRT for treating lung or liver tumors, which move as a patient breathes. The results of these studies have suggested that SBRT favorably controls tumors in the case of moving lesions.
Four-dimensional computed tomography (4D-CT) with an abdominal compressor (AC) is clinically convenient for effective respiratory motion management. Because this method is noninvasive and allows free breathing, its use reduces complications. Furthermore, patients consider this method convenient. Moreover, it is considered more efficient than other methods of respiratory motion management by physicians and therapists. The use of 4D-CT with an AC for treating pulmonary lesions has also been widely investigated, and the technique is gaining acceptance for treating hepatic lesions. However, the protocols for using 4D-CT with an AC for treating hepatic lesions are different from those used for treating pulmonary lesions. In this article, we describe a new protocol for SBRT with 4D-CT and an AC for treating liver metastases.

Stereotactic body radiotherapy (SBRT) requires rigorous accuracy and precision for delivering high radiation doses per fraction to small treatment volumes to improve tumor control and simultaneously reduce toxicity. Herein, we present a noninvasive and clinically convenient respiratory motion management protocol for SBRT for liver metastases.

The prognosis of patients with metastatic cancers has improved in the past decades due to effective chemotherapy and oligometastatic surgery. For ...

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 ...

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 ...

Application of Separation Surgery Combined with Radiofrequency Ablation and Bone Cement Strengthening in Thoracolumbar Metastasis

The spine is a common site for metastatic tumors, with 5%-10% of patients developing epidural spinal cord compression (ESCC), which significantly reduces their quality of life and accelerates the process of death. When total en-bloc spondylectomy (TES) radical surgery does not achieve the desired tumor control, palliative care remains the primary treatment option. Traditional laminar decompression or partial tumor resection can only relieve local compression. Although the surgical trauma and complications are less, these methods cannot effectively address tumor recurrence and secondary compression. Therefore, separation surgery combined with radiofrequency ablation and bone cement strengthening was used to treat thoracolumbar metastatic tumors, aiming to achieve good clinical results. In this protocol, the steps and key points of separation surgery combined with radiofrequency ablation and bone cement reinforcement for thoracolumbar metastatic tumors are introduced in detail. Meanwhile, the clinical data of 67 cases of thoracolumbar metastatic tumors in our hospital meeting the inclusion criteria were retrospectively analyzed. Different treatment methods divided the patients into two groups: separation surgery combined with radiofrequency ablation and bone cement strengthening (group A, 33 cases) and the radiotherapy group (group B, 34 cases). All patients were evaluated using improved Tokuhashi, Tomita, SINS, and ESCC scores before treatment. VAS score, Frankel grading, and Karnofsky scores during different periods of the two treatments were compared to assess the clinical outcomes. Studies have shown that separation surgery combined with radiofrequency ablation and bone cement strengthening can significantly reduce pain, promote neurological function recovery, enhance mobility, and improve quality of life in treating thoracolumbar metastatic tumors.

This study investigates the efficacy of combining separation surgery with radiofrequency ablation and radiotherapy in treating thoracolumbar metastatic tumors.

The spine is a common site for metastatic tumors, with 5%-10% of patients developing epidural spinal cord compression (ESCC), which significantly reduces ...

Reducing Bleeding in Laparoscopic Partial Splenectomy with Microwave Ablation

Application of Microwave Ablation in Laparoscopic Partial Splenectomy

Splenic hemangioma is the most common pathological classification of splenic tumors, and its surgical indication and treatment have been controversial. Before, open splenectomy was usually used to treat splenic hemangioma. Following the rapid development of laparoscopic techniques, people's requirements for minimally invasive treatment have gradually increased, and laparoscopic splenectomy has gradually become the main treatment method. However, through the deeper study of spleen function, it was found that partial splenectomy can cut down the incidence of postoperative thrombocythemia and decrease side effects on the physiological function of the body, so laparoscopic partial splenectomy came into being. However, due to the special anatomical structure, the incidence of hemorrhage during partial splenectomy is greater. Therefore, during the operation, we removed part of the splenic blood vessels, combined with microwave ablation, which perfectly solved the problem of intraoperative bleeding. Laparoscopic partial splenectomy combined with microwave ablation not only achieves the requirements of minimally invasive treatment but also reduces the risk of intraoperative bleeding, meriting clinical application and promotion.

The use of laparoscopic partial splenectomy has been limited due to the high risk of bleeding during surgery. Therefore, we introduce a laparoscopic method combined with microwave ablation to solve the problem of intraoperative bleeding.

Splenic hemangioma is the most common pathological classification of splenic tumors, and its surgical indication and treatment have been controversial. ...