Laparoscopic Anatomical Resection Research Articles

Caudo-dorsal approach combined with the occlusion of right hepatic vein and Pringle maneuver in laparoscopic anatomical resection of segment 7.

Laparoscopic anatomical resection of segment 7 (LARS7) remains a technically challenging procedure due to the deep anatomical location and the potential risk of injury to the right hepatic vein (RHV). Herein, we initiated an innovative technique of caudo-dorsal approach combined with the occlusion of the RHV and Pringle maneuver for LARS7 and presented the outcomes of our initial series. Since January 2021, the patients who underwent LARS7 by using this novel technique were enrolled in this study. The critical aspect of this technique was the interruption of communication between the RHV and the inferior vena cava. Meanwhile, the Pringle maneuver was adopted to control the hepatic inflow. A total of 11 patients underwent LARS7 by using this novel technique, which included 8 hepatocellular carcinoma, 2 bile duct adenocarcinoma and one focal nodular hyperplasia. The median operative time was 199min (range of 151-318min) and the median blood loss was 150ml (range of 50-200ml). The main trunk of the RHV was fully exposed on the cutting surface in all cases and no patient received perioperative blood transfusion. No procedure was converted to open surgery. Of note, no indications of CO2 gas embolism were observed in these cases after the introduction of double occlusion. Only one patient suffered from postoperative complications and healed after treatment. The median postoperative stay was 5days (range of 4-7days). The 90-day mortality was nil. At a median follow-up period of 19months, all of the patients were alive without any evidence of tumor recurrence. The caudo-dorsal approach combined with the occlusion of RHV and the Pringle maneuver may be a feasible and expected technique for safe exposure of RHV in LARS7. Further validation of the feasibility and efficacy of this technique is needed.

Laparoscopic anatomical versus non-anatomical liver resection for hepatocellular carcinoma in the posterosuperior segments: a propensity score matched analysis.

Since laparoscopic anatomical resection (LAR) for tumors, especially located in the posterosuperior (PS) segments of the liver remains difficult, laparoscopic non-anatomical resection (LNAR) are generally preferred. To compare the clinical outcomes between LAR and LNAR for hepatocellular carcinoma (HCC) located in the PS segments. We retrospectively reviewed the data for 1,029 patients who underwent hepatectomy for HCC between 2004 and 2019. Of 167 patients who underwent laparoscopic hepatectomy for HCC in PS segments, 64 underwent LNAR and 103 underwent LAR. Patients were matched one-to-one using propensity score matching (46:46). LNAR was associated with significantly shorter operation time (P=0.001), lower estimated blood loss (P=0.001), lower transfusion rate (P=0.006) and shorter hospital stay (P=0.012) than LAR. The respective 1- ,3-, and 5-year overall survival rates (LAR: 95.3%, 87.1%, and 77.8%; LNAR: 96.7%, 91.6%, and 85.0%; P=0.262) and recurrence-free survival rates (LAR: 75.7%, 70.3%, and 68.9%; LNAR: 81.8%, 58.3%, and 55.3%; P=0.879) were similar. The intrahepatic recurrence rate was significantly higher in LNAR group than in LAR group (78.6% vs. 57.1%, P=0.023), but the post-recurrence treatments differed significantly between the two groups (P=0.016); the re-resection rate was much greater in the LNAR group (45.0% vs. 0%) group. The respective 1-, 3-, and 5-year post-recurrence survival rates were similar in the LAR and LNAR groups (P=0.212). After recurrence, survival in re-resection group was significantly greater than not (P=0.026). LNAR is safe and feasible for HCC located in PS segments, and provided acceptable oncologic outcomes that are comparable to those of LAR. LNAR can be considered for patient with tumor located in PS segment when LAR is not feasible.

Anatomical liver resection using the ultrasound-guided compression technique in minimal access surgery.

Segmental or subsegmental anatomical resection (AR) of hepatocellular carcinoma (HCC) in minimal access liver surgery (MALS) has been technically proposed. The Glissonean approach or dye injection technique are generally adopted. The tumor-feeding portal pedicle compression technique (C-AR) is an established approach in open surgery, but its feasibility in the MALS environment has never been described. Eligible patients were prospectively enrolled to undergo laparoscopic or robotic ultrasound-guided C-AR based on HCC location and preoperative identification of a single tumor-feeding portal pedicle. Initial C-AR experience was gained with laparoscopic cases in the beginning of 2020. Following our progressive experience in laparoscopic C-AR, patients requiring AR for HCC were consecutively selected for robotic C-AR. A total of 10 patients underwent minimal access C-AR. All patients had Child-Pugh A HCC. The surgical procedures included 6 laparoscopic and 4 robotic C-AR. Median tumor size was 3.1cm (range 2-7cm). All procedures had R0 margin. Postoperative complications were nil. C-AR technique is a feasible and promising technique for patients eligible for laparoscopic and robotic AR for HCC. Further data are necessary to validate its applicability to more complex minimal access AR.

Optimal Dosage of Indocyanine Green Fluorescence for Intraoperative Positive Staining in Laparoscopic Anatomical Liver Resection.

Introduction Fluorescence imaging technology, specifically utilizing indocyanine green (ICG), has emerged as a valuable tool in laparoscopic hepatectomy. In particular, laparoscopic anatomical liver resection (ALR) has benefited from the implementation of both positive and negative staining methods. A case series study reported a success rate of 53% for the positive staining method, citing potential issues regarding the proper ICG dosage needed for accurate fluorescence. Thus, it is crucial to conduct research to investigate the optimal dosage for ICG-positive staining in clinical practice to maximize the benefits of this technique. Materials and methods This retrospective study was conducted at a single center, Meiwa Hospital, and received approval from the hospital's ethics committee in accordance with the Helsinki Declaration. We reviewed the records of 264 patients who underwent open and laparoscopic hepatectomies for benign and malignant liver diseases from January 2019 to January 2023. Of these, 18 patients who underwent laparoscopic ALR with the ICG-positive staining method were evaluated. Fluorescence-emitting segmental borders were assessed immediately after puncture (first stage) and during parenchymal dissection (second stage). In the first stage, we evaluated the intensity of fluorescence emission, categorizing it as "strong" or "weak." The absence of visible fluorescence emission was considered a puncture failure. During the second stage of evaluation, from parenchymal resection to completion, we assessed the sustainability of fluorescence emission, defining it as "clear" or "contaminated." Both evaluations were subjectively judged by three surgeons at our center. The ICG quantity per targeted portal vein-bearing liver volume (mg/100 mL) was calculated for each patient, and the optimal dosage was determined using receiver operating characteristic (ROC) curve analysis. To ascertain the minimum value for adequate fluorescence emission intensity, ROC curve analysis was performed to discriminate between binary outcomes of "strong" or "weak" emission. Furthermore, to establish the maximum value for maintaining a clear fluorescence border, ROC curve analysis was conducted to discriminate between "clear" and "contaminated" during the second evaluation. Results Among the 18 successful puncture cases, the first-stage evaluation of fluorescence intensity revealed 14 punctures with "strong" intensity and four punctures with "weak" intensity. In the second-stage evaluation, 13 cases demonstrated "clear" borders, while five cases exhibited "contaminated" borders. ROC curve analysis was performed to determine the optimal ICG dose for adequate fluorescence intensity and preservation of clear borders during dissection. The analysis indicated that the appropriate ICG dose for achieving optimal intensity was 0.028 mg/100 mL (area under the curve [AUC]: 0.893), while the dose that prevented contamination of fluorescence in non-target areas until after dissection was 0.083 mg/100 mL (AUC: 0.723). Conclusions Laparoscopic anatomical resection using the positive staining method requires an optimal ICG dosage of 0.028-0.083 mg per 100 mL of liver volume. By employing this methodology, more precise and safer laparoscopic anatomical resections can be conducted, thereby enhancing the safety of the surgical procedure for patients.

Augmented Reality Navigation Plus Indocyanine Green Fluorescence Imaging Can Accurately Guide Laparoscopic Anatomical Segment 8 Resection.

Laparoscopic anatomical Segment 8 (S8) resection is a highly challenging hepatectomy. Augmented reality navigation (ARN), which could be combined with indocyanine green (ICG) fluorescence imaging, has been applied in various complex liver resections and may also be applied in laparoscopic anatomical S8 resection. However, no study has explored how to apply ARN plus ICG fluorescence imaging (ARN-FI) in laparoscopic anatomical S8 resection, or explored its accuracy. This study is a post hoc analysis that included 31 patients undergoing laparoscopic anatomical S8 resection from the clinical NaLLRFI trial, and the resected liver volume was measured in each patient. The perioperative parameters of safety and feasibility, as well as the accuracy analysis outcomes were compared. There were 16 patients in the ARN-FI group and 15 patients underwent conventional laparoscopic hepatectomy without ARN or fluorescence imaging (non-ARN-FI group). There was no significant difference in baseline characteristics between the two groups. Compared with the non-ARN-FI group, the ARN-FI group had lower intraoperative bleeding (median 125 vs. 300 mL, P = 0.003). No significant difference was observed in other postoperative short-term outcomes. Accuracy analysis indicated that the actual resected liver volume (ARLV) in the ARN-FI group was more accurate. ARN-FI was associated with less intraoperative bleeding and more accurate resection volume. These techniques may address existing challenges and provide rational guidance for laparoscopic anatomical S8 resection.

Laparoscopic Anatomical Resection of Paracaval Portion of Caudate Lobe and Segment 8 for HCC in a HCV-related Cirrhotic Patient

Laparoscopic Anatomical Resection of Paracaval Portion of Caudate Lobe and Segment 8 for HCC in a HCV-related Cirrhotic Patient

Laparoscopic Anatomic Liver Resection of the Dorsal Part of Segment 8 Using an Hepatic Vein-Guided Approach

Laparoscopic anatomic liver resection is considered highly challenging, especially in segment 8 (S8), owing to the limited angle of the laparoscope and limited manipulation of the surgical instrument1,2. Additionally, resection is technically difficult when approaching the more peripheral branches since the Glissonean pedicle of S8 has several variations3 and is far from the hepatic hilum. The hepatic vein (HV)-guided approach involves entering from the cranial side of the liver while overcoming these difficulties with the unique view and techniques of laparoscopy4,5. We describe laparoscopic anatomic resection of the dorsal part of S8 using the HV-guided approach for hepatocellular carcinoma. The drainage vein of segment 8 (V8), which often runs between the ventral and dorsal parts of S86,7, was exposed from the confluence of the middle HV to the periphery. The dorsal Glissonean branch of S8 (G8dor) was identified by deep dissection of the parenchyma on the right side of the V8. The right HV (RHV) was exposed toward the periphery after dissecting the G8dor. Liver parenchymal dissection was completed by connecting the demarcation line and the RHV. The total operation time was 319 min, estimated blood loss was 5mL, and the patient was discharged on postoperative day 6 with no complications. Laparoscopic anatomic resection of the dorsal parts of S8 could be safely performed by exposing the HVs from their roots and using the HVs as a landmark to identify the intrahepatic Glissonean pedicles.

Laparoscopic anatomical S8 segmentectomy by Glissonian approach after dissection of the midplane of the liver

Anatomical resection of the liver in HCC is important in terms of oncologic benefit. However, laparoscopic anatomical segment 8 (S8) resection is anatomically complex and technically difficult. Ultrasonography guided dye or ICG injection technique can be a good option, but it is technically demanding and experience dependent. A 56-year-old female with underlying chronic hepatitis B virus was diagnosed with 1.8 cm sized HCC in S8. The tumor was suspected of the microvascular invasion near the middle hepatic vein (MHV) in MRI. Laparoscopic ultrasonography was used to identify the location of mass and the relation to the vasculature. The lower 2/3 of the midplane of the liver was dissected. The branches of MHV draining S4 were divided to get resection margin. After dissection around the right anterior Glissonian pedicle, ligation of S8 pedicle was done. Then, lateral border of S8 was dissected along the ischemic line. MHV was crossed over during the dissection of the upper 1/3 of the midplane of the liver. S8 was anatomically resected. The operative time was 185 minutes, and the estimated blood loss was 100 mL. The final pathology was HCC and the size of tumor was 18 mm with 2 cm safety margin. Follow up CT scan showed congestion in S4 and S5, but no other problems. The patient was discharged on postoperative day 5 without complication. Laparoscopic anatomical resection of S8 using Glissonian approach after dissection of the midplane of the liver was feasible and it is simpler and easier to apply than dye injection technique.

Laparoscopic Anatomic Resection Guided by Indocyanine Green Fluorescence Imaging - A Single Institution Experience -

In laparoscopic anatomic resection, especially in the sub-segmentectomy of segment 8 or 7, it can be difficult to detect and dissect the targeted branch of Glisson sheath from the hepatic hilum. When that is the case, we inject dye into the targeted portal vein to stain the resection area by using an ultrasound-guided vascular access system for laparoscopic surgery. We use the Bk5000/9066 (BK medical) ultrasound machine with a built-in probe for ultrasound-guided vascular access. This system has an advanced laparoscopic ultrasound transducer that has a small hole for the needle on the tip of the probe which can draw a guideline for the needle. We also use the laparoscope Indocyanine Green (ICG) fluorescence imaging camera system (Storz). The dye is a mixture of ICG and Indigo carmine. Under guidance of ultrasonography, we detect the targeted portal vein and percutaneously insert the PTCD needle into the portal vein. Then, we slowly inject the dye observing the dyeing process with the ICG imaging camera. By using ICG together with Indigo carmine we can detect the color contrast between the area to be resected and the rest of the liver more precisely, especially when we cannot get a clear border line with Indigo carmine for whatever reason. The US-guided injecting ICG together with Indigo carmine into the targeted portal vein can draw a demarcation line more efficiently and clearly than was previously possible. This system should be useful, especially in the laparoscopic anatomic resection of the sub-segment or a smaller area.

3D laparoscopic anatomical segment 8 resection for colorectal liver metastasis recurrence after previous left hemi-hepatectomy

Purpose: Patients suffering from colorectal liver metastasis (CRLM) often have recurrent disease and many patients will undergo multiple surgical procedures during the course of their disease. Redo hepatic surgery can be notoriously difficult. In this video we will show a case of 3d laparoscopic anatomical segment 8 resection after previous left hemi-hepatectomy for CRLM. Method: This 75 year old patient had a local recurrence of a metastasis of her colon cancer (pT2N0, 2014) at the previous resection plane after left hemi-hepatectomy (2019, R1). The recurrence was in contact with the right anterior pedicle. The patient had stable disease after 10 cycles of chemotherapy (Folfox- Bevacizumab) and was considered for surgery. Preoperative calculation of FLR for segment 5/8 resection showed a 34% FLR. Extensive chemotherapy was administered preoperatively suggesting chemotherapy induced liver injury. A pre-operative portal embolization of P8 was performed to induce hypertrophy of the FLR. CT scan 6 weeks after embolization showed no apparent hypertrophy in S6/7. Results: A 3D laparoscopic anatomical S8 resection was performed. Segment 5 could be preserved by selective transection of S8 pedicle. Operation and peri-operative course were uneventful. Operative time of 3hours, estimated blood loss of 250ml. No postoperative liver insufficiency. TOSGS 0, patient went home POD 3. Conclusion: Laparoscopic redo hepatic surgery after previous major hepatectomy is technically challenging, but can safely be performed with low morbidity and good oncological outcomes.

Application of Indocyanine Green Fluorescence Imaging in Laparoscopic Liver Surgery

To study the clinical use of indocyanine green(ICG)fluorescence imaging in laparoscopic liver surgery, the clinical and pathological data of 68 patients who underwent laparoscopic hepatectomy using the ICG fluorescence imaging technique during the study period from September 2016 to October 2018 in Zhongnan Hospital of Wuhan University were retrospectively analyzed. Analysis was carried out on the surgical methods, fluorescence navigation methods, ICG injection time and dose, tumor characteristics, and pathological studies of the resected specimens. Of 68 patients, only 3 patients were converted to open surgery. 32 patients underwent ICG fluorescent guided laparoscopic anatomical resection of lower hepatic segment/hepatic hemilivers(positive staining in 17 patients, negative staining in 15 patients), with 19 patients successfully staining with ICG(59.4%). Postoperative histopathology showed primary hepatic solid tumors(n=31), secondary liver tumors(n=12), hepatic cysts(n=4), hepatic hemangiomas(n=5), hepatolithiasis(n=12)and hepatic focal nodular hyperplasia(n=1). These lesions were combined with hepatitis B liver fibrosis in 29 patients. ICG fluorescence imaging positively impacted on laparoscopic liver surgery. Proper preoperative ICG injection was helpful for the identification, localization and intraoperative surgical guidance of tumors, especially for patients with deep-seated and central tumors. As a consequence, oncological and surgical safety of laparoscopic liver surgery was improved. Targeted visualization of liver segments and surgical navigation using intraoperative ICG injections facilitated accurate and precise resection of anatomical liver segments or hemi-hepatectomies. The use of intraoperative ICG fluorescence technology for hepatic hemangioma, hepatic cyst, intrahepatic bile duct stones and other benign liver lesions, helped to improve safety of surgery.

Pure Laparoscopic Anatomical Resection of Segment 4b for Hepatocellular Carcinoma Using the Transfissural Glissonean Approach

BackgroundAnatomical segmentectomy is a technically challenging procedure because tertiary portal pedicles are multiple, variable, and deep inside the liver.1 Anatomical segmentectomy can be performed using the transfissural Glissonean approach through the opening main portal fissure or umbilical fissure.1-3 We present laparoscopic anatomical resection of segment 4b using the transfissural Glissonean approach. MethodsA 67-year-old man was referred for treatment of single nodular mass in segment 4b. The surgical procedure involved the following steps: (1) Opening of the umbilical fissure along the umbilical fissure vein (2) Dissection of Glissonean pedicle 4b (3) Identification of ischemic territory of segment 4b (4) Right-side parenchymal transection along the ischemic line. ResultsThe operative time was 230 min, and the estimated blood loss was 100 mL. The final histopathological diagnosis was hepatocellular carcinoma. The tumor size was 30 mm and the resection margin was 25 mm. The patient had an uneventful postoperative recovery, and he was discharged on postoperative day 6. ConclusionThe transfissural Glissonean approach for laparoscopic anatomic resection of segment 4 b is a feasible and effective technique. The opening of the umbilical fissure allows the surgeon to dissect the target portal pedicles of segment 4b directly.

Branch-type intraductal papillary neoplasm of the bile duct treated with laparoscopic anatomical resection: a case report

BackgroundIntraductal papillary neoplasm of the bile duct (IPNB) is characterized by an intraluminal, growing papillary tumor covered by neoplastic biliary epithelial cells with a fine fibrovascular core. IPNB was introduced as a precancerous and early neoplastic lesion in the 2010 World Health Organization classification of tumors of the digestive system. IPNB eventually invades the bile duct wall and progresses to invasive cholangiocarcinoma. IPNB resembles intraductal papillary mucinous neoplasm of the pancreas (IPMN), particularly the main pancreatic duct type.IPNB cases, possibly corresponding to branch-type IPMN, have been recently reported, and these cases involved the peribiliary glands significantly and showed gross cystic dilatation. Small branch-type intrahepatic IPNB often mimics simple liver cysts, making the diagnosis of IPNB difficult. Some literature recommended surgical resection for treatment. Laparoscopic resection is a good treatment option for small tumor. We herein present the case of branch-type IPNB that was treated with laparoscopic anatomical liver resection 5 years after being detected.Case presentationA 64-year-old woman was undergoing follow-up for primary aldosteronism. In 2012, follow-up computed tomography (CT) incidentally revealed a 7-mm cystic lesion in segment 8 of the liver. From 2012 to 2017, the cystic lesion kept increasing in size, reaching 17 mm. In 2017, CT also revealed a 13-mm mural nodule in the cyst wall. Therefore, the patient was referred to our department for possible malignancy.We suspected a branch-type IPNB; however, the mass was small and diagnosis could not be made without performing biopsy. Accordingly, surgical resection was performed for diagnosis and treatment. Because branch-type IPNB might show horizontal spread through the intrahepatic bile duct, we believed that anatomical resection of the liver was appropriate considering the malignant potential of the lesion. Therefore, laparoscopic anatomical resection of segment 8 of the liver was performed. The resected tumor measured 17 mm and was histologically diagnosed as a high-grade IPNB.ConclusionBranch-type IPNBs are rare but can potentially lead to malignant tumors. Surgical resection is the treatment of choice, with laparoscopic anatomical resection being a good treatment option for this small tumor.

Laparoscopic Anatomical Segment VII Resection for Hepatocellular Carcinoma Using the Glissonian Approach with Indocyanine Green Dye Fluorescence

BackgroundMany studies confirm that anatomical resection was associated with favorable oncologic outcomes for patients with HCC who had preserved as much of the remnant liver tissue as possible.1,2 In recent years, laparoscopic liver resection has been widely extended from minor resection to complex hepatectomy,3 However, surgery on tumors located in the posterosuperior segment remains a demanding procedure regardless of the extent of resection.4 Laparoscopic anatomical segment VII resection has one of the highest difficulty scores based on the tumor location due to poor accessibility, hard to exposure, and difficulty in obtaining sufficient surgical margins.5,6 Here, we report a totally laparoscopic anatomical VII resection using the Glissonian approach with indocyanine green dye fluorescence. MethodsA 74-year-old man with a body mass index of 31.9 kg/m2 suffered from HBV-related cirrhosis was admitted to our institution. The preoperative Gd-EOB-DTPA MRI showed a 2.7-cm HCC located in segment VIII. The preoperative AFP is 3431 ng/ml. A true anatomical segmentectomy was performed by using selective occlusion of segment VII Glissonian pedicle, which was identified from the liver hilum. Indocyanine green (ICG) dye demarcation was used as a guidance during parenchymal transection. ResultsThe operative time was 270 min with an estimated blood loss of 200 mL. The postoperative course was uneventful. Drainage tube was pulled out on the fourth day. The pathology confirmed the diagnosis of hepatocellular carcinoma and the surgical margin was negative. The patient was discharged on the 8th day after operation. ConclusionsTotally laparoscopic anatomical segment VII resection is a technically challenging operation. Advanced laparoscopic skills are necessary to complete such a difficult procedure safely. Glissonian approach and ICG fluorescence imaging guide parenchyma resection could be help.

ASO Author Reflections: Laparoscopic Anatomical Resections: Where We Are and Where Should We Go.

ASO Author Reflections: Laparoscopic Anatomical Resections: Where We Are and Where Should We Go.

Changes and optimization of operator model in laparoscopic anastomic hepatectomy

Laparoscopic anatomical resection (LAR) is a highly-demanding and high risky procedure. Traditional single-surgeon technique appears to be frustrating when dealing with intro-operative emergency and ensuring the safety of complicated LAR. The authors′ department has applied two-surgeon technique when performing LAR since 2014. In complicated cases of LAR, two skillful surgeons cooperate to perform surgeries. The two surgeons stand at each side of the patient and switch their duties as the surgeon or the assistant during the operation. Experience of the authors’ department shows that compared with single-surgeon technique, two-surgeon technique can help better deal with intro-operative accidental events such as hemorrhage and guarantee the safety of LAR, as well as enhance the efficiency and quality of procedures. Two-surgeon technique benefits team building and training young laparoscopic liver surgeons, and help them pass the learning curve more safely and quickly. Key words: Anatomical liver resection; Single-surgeon technique; Two-surgeon technique; Laparoscopy

Pure Laparoscopic Anatomical Resection of the Ventral Area of the Right Anterior Section Using the Transfissural Glissonean Approach

The introduction of the anatomical concept of classifying the right anterior section (RAS) into the ventral and dorsal areas enabled the development of limited resection of the ventral or dorsal area. Anatomical resection of the ventral area of the RAS is technically demanding because it requires determination of the boundary of the ventral area and two large of transection planes. We present a technique for laparoscopic anatomical resection of the ventral area of the RAS using a transfissural Glissonean approach.In the transfissural Glissonean approach, the portal or umbilical fissure is opened after liver parenchymal dissection, and then, the surgeon can confirm the Glissonean pedicles and territory. The procedure was as follows: (1) dissection of the right anterior portal pedicle (RAPP) for the identification of the main portal fissure, (2) opening of the main portal fissure, (3) dissection and clamping of the ventral branch of the RAPP, and (4) transection of the borderline of the ventral and dorsal areas.The transfissural Glissonean approach is a feasible and effective technique for laparoscopic anatomical resection of the ventral area of the RAS. Opening the main portal fissure allows easy and direct access to the ventral branch of the RAPP.

Sentinel Lymph Node Sampling for Early Gastric Cancer—Preliminary Results of A North American Prospective Study

IntroductionAlthough endoscopic resection for early gastric cancer is well established, anatomical resection with regional lymphadenectomy is recommended for lesions at high risk for occult lymph node metastasis (e.g., lymphovascular invasion, poor grade, and deep submucosal invasion). However, 75–95% high-risk early gastric cancer (HR-EGC) patients ultimately have node-negative disease and could potentially have undergone organ-sparing resection. Due to the inadequacy of standard modalities to reliably rule out nodal metastases in HR-EGC patients, sentinel lymph node (SLN) sampling was developed in Asia with promising results. However, the applicability of this technique in the West has been brought into question due to potential differences in tumor histology and body habitus. This prospective study aimed to test SLN sampling for North American EGC patients. MethodsAll patients with biopsy-confirmed T0–2 N0–1 M0 gastric adenocarcinoma at the Montreal General Hospital-McGill University Health Centre were eligible for enrollment. Esophageal and GEJ cancers were excluded due to the high rate of intrathoracic lymph node involvement. Peritumoral submucosal injection with T99 radiocolloid was performed endoscopically 24–30 h prior to surgery. Methylene blue dye injection was performed after induction of anesthesia. SLN basins were identified as those having > 10% of baseline tumor radiation signal or blue color, or both. After basins were individually removed, standard laparoscopic anatomical resection was then performed with D2 lymphadenectomy. (ClinicalTrials.gov identifier: NCT03049345). Data are presented as median (interquartile range). ResultsFrom July 2016–April 2018, 253 patients with esophagogastric adenocarcinoma were evaluated. Of these, 10 met inclusion criteria (90% male, age 66(30) years). Subtotal gastrectomy was performed in nine patients (90%) and length of stay was 4 (2) days. At least one SLN basin was identified in nine cases (90%). The median #SLN basins identified was 2(2) with a median of 5(5) total SLNs retrieved per patient. In the one case for which no SLN basins were identified, only blue dye injection was used, whereas SLNs were identified in all cases using the dual tracer method. Final T-stage was pT1b/T2 in four (40%), pT1a in two (20%), and Tx in four (40%). Two patients (20%) had lymph node metastases on final pathological analysis, both of which were identified by SLN sampling (accuracy 100%; false negative rate 0%). No adverse events related to SLN retrieval were identified. ConclusionsThis study represents the first prospective feasibility evaluation of sentinel lymph node sampling for early gastric cancer in North America with promising preliminary results. The dual tracer method was superior to single agent blue dye in identifying sentinel nodal basins. Considerable further study is necessary to verify the safety and utility of SLN mapping in North American patients with early gastric adenocarcinoma.

Application of indocyanine green fluorescence imaging in laparoscopic liver surgery

Objective To study the clinical use of indocyanine green (ICG) fluorescence imaging in laparoscopic liver surgery. Methods The clinical and pathological data of 68 patients who underwent la-paroscopic hepatectomy using the ICG fluorescence imaging technique during the study period from September 2016 to October 2018 in Zhongnan Hospital, Wuhan University were retrospectively analyzed. Analysis was carried out on the surgical methods, fluorescence navigation methods, ICG injection time and dose, tumor characteristics, and pathological studies of the resected specimens. Results Of 68 patients, 3 patients were converted to open surgery, and the remaining 65 patients completed the ICG fluorescence laparoscopic hepatectomy. Thirty-two of these 65 patients underwent ICG fluorescent guided laparoscopic anatomical resection of lower hepatic segment / hepatic hemilivers (positive staining in 17 patients, negative staining in 15 patients), with 19 patients successfully staining with ICG(19 / 32, 59.4%). Postoperative histopathology showed primary hepatic solid tumors (n=31), secondary liver tumors (n=12), hepatic cysts (n=4), hepatic hemangiomas (n=5), hepatolithiasis (n=12) and hepatic focal nodular hyperplasia (n=1). These lesions were combined with hepatitis B liver fibrosis in 29 patients. Conclusions ICG fluorescence imaging positively impacted on laparoscopic liver surgery. Proper preoperative ICG injection was helpful for the identification, localization and intraoperative surgical guidance of tumors, especially for patients with deep-seated and central tumors. As a consequence, oncological and surgical safety of laparoscopic liver surgery was improved. Targeted visualization of liver segments and surgical navigation using intraoperative ICG injections facilitated accurate and precise resection of anatomical liver segments or hemi-hepatectomies. The use of intraoperative ICG fluorescence technology for hepatic hemangioma, hepatic cyst, intrahepatic bile duct stones and other benign liver lesions, helped to improve safety of surgery. Key words: Liver neoplasm; Laparoscopes; Indocyanine green; Fluorescence imaging; Hepatectomy

Laparoscopic anatomical resection of segment 7 and segment 8 when right hepatic vein reconstruction was not necessary

Introduction: For a huge liver cancer in segment 7 and 8 with right hepatic vein (RHV) involvement, some patients with large inferior right hepatic veins (IRHV) can avoid complex vascular reconstruction after en bloc resection of segment 7 and 8 and RHV. In such a situation, safe laparoscopic surgery becomes possible. Method: This is a case report about a 9.7cm HCC in segment 7 and 8 with RHV involvement inside liver parenchyma. This patient had at least two large IRHV in computed tomography. In this operation, I transected the parenchyma along the middle hepatic vein first to create a midline plane. Then the right major Glisson's pedicle and S8 pedicle next to it were exposed in parenchyma from the opened liver midline. After S8 pedicle was transected, I advanced the dissection between segment 5 and 8 ( the transverse plane) and cut the tributaries and the dominant tract of RHV in this plane. The surface of a large IRHV was exposed in this transverse plane too. In another direction, I deepened the midline plane to expose IVC superior to the liver hilum. The root of RHV was ligated and cut from IVC. The root of the large IRHV on IVC was exposed in this midline plane between RHV and liver hilum. So, the large IRHV was preserved in both midline and transverse plane. I further advanced the parenchyma dissection to cross the surface of IRHV, and then deepened the dissection dorsally to separate the segment 7 & 6. Triangular and coronary ligaments were cut at last. Result: Hepatopetal portal flows were all preserved. Conclusion: In summary, this laparoscopic operation was performed using caudal to cranial (midline), medial to lateral ( between S5-S8), and ventral to dorsal (between S6-S7) approach. There was not any dissection between IVC and segment 1 right portion behind liver hilum.