New Scale Predicting Distant Recurrence in Locally Advanced Lower Rectal Cancer Patients After Neoadjuvant Chemoradiotherapy.

BACKGROUND/AIM: Neoadjuvant chemoradiotherapy (nCRT) for locally advanced lower rectal cancer (LALRC) is effective in preventing locoregional recurrence; however, it is less effective for preventing distant recurrence. This study aimed to evaluate a new scale for predicting distant recurrence before administering nCRT. PATIENTS AND METHODS: Sixty-three patients underwent nCRT for LALRC between 2009 and 2016 at the Tokyo Women's Medical University. Of these, 51 consecutive patients who underwent curative surgery were enrolled in this study. Patients with ≥cT3 status or cN-positive LALRC were classified into three groups before nCRT based on the neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR): high-risk, NLR ≥3.2 and LMR <5.0; intermediate-risk, NLR <3.2 and LMR ≥5.0 or NLR ≥3.2 and LMR <5.0; and low-risk, NLR <3.2 and LMR ≥5.0. Independent risk factors associated with distant relapse-free survival were analysed using the Cox proportional hazards model. Relapse-free survival from distant metastasis was evaluated using the log-rank test. RESULTS: Patient characteristics and tumour-associated factors were not significantly different between the groups. Distant recurrence in the high-, intermediate-, and low-risk groups was 61.5%, 42.9%, and 20.8% (p=0.046), respectively. In the multivariate analysis, the new scale was an independent risk factor for distant relapse-free survival (high-risk vs. low-risk groups, p=0.004 and intermediate-risk vs. low-risk groups, p=0.055). The 3-year distant relapse-free survival rate in the high-, intermediate-, and low-risk groups was 38.5%, 56.3%, and 81.7% (p=0.028), respectively. CONCLUSION: A new scale combining the pre-nCRT NLR and LMR was independently associated with distant relapse-free survival. The new scale for LALRC may aid selection for total neoadjuvant chemotherapy.

Prognostic risk factors for pT4 colon cancer: A retrospective cohort study.

The present study aimed to clarify the prognostic risk factors for pathological T4 (pT4) colon cancer and provide a basis for improved treatment in affected patients. The current retrospective cohort study included 83 consecutively enrolled patients who underwent curative surgery for primary pT4 colon cancer between January 2014 and December 2021 at Tokyo Medical Women's University (Tokyo, Japan). Oncological outcomes, including recurrence pattern, were compared between patients with pT4a and pT4b colon cancer. Independent risk factors associated with overall survival (OS) and relapse-free survival (RFS) were analyzed using a multivariate Cox regression model. The 3-year OS rates were 85.1 and 95.0% in the pT4a and pT4b groups (P=0.089) and 3-year RFS rates were 64.1 and 60.5% (P=0.589), respectively. Moreover, the 3-year peritoneal recurrence-free survival was 71.0 and 90.2% (P=0.085) in these groups, respectively. Independent risk factors for OS were histology (mucinous or poorly differentiated adenocarcinoma), tumor location (right-sided) and pN status (positive). The risk factors for RFS were histology and pN status. Patients with pT4b colon cancer and R0 resection may not have a poorer prognosis compared with those with pT4a colon cancer. However, patients with pT4a colon cancer tended to have more peritoneal recurrence patterns. Histology and pN status were associated with OS and RFS, and right-sided colon cancer was also a risk factor for OS.

Marked improvement of severe reflux esophagitis following proximal gastrectomy with esophagogastrostomy by the right gastroepiploic vessels-preserving antrectomy and Roux-en-Y biliary diversion.

Duodenogastroesophageal reflux (DGER) following esophagectomy or gastrectomy can cause severe esophagitis, which impairs patients' quality of life and increases the risk of esophageal carcinogenesis. It is sometimes resistant to medical treatment, and surgical treatment is considered effective in such cases. However, an optimal operative procedure for medical treatment-resistant reflux esophagitis (RE) after proximal gastrectomy (PG) with esophagogastrostomy (EG) has not yet been established. We performed the right gastroepiploic vessels-preserving antrectomy and Roux-en-Y biliary diversion in a 70-year-old man with medical treatment-resistant severe esophagitis caused by DGER following PG with EG for esophagogastric junction cancer. The postoperative course was uneventful, and esophagogastroduodenoscopy performed on the 19th postoperative day showed marked improvement in the esophageal erosions. The patient reported symptomatic relief. The right gastroepiploic vessels-preserving antrectomy and Roux-en-Y biliary diversion were considered safe and feasible for medical treatment-resistant RE following PG with EG.

History of the lymph node numbering system in the Japanese Classification of Gastric Carcinoma since 1962.

The Japanese Classification of Gastric Carcinoma was established by the Japanese Research Society for Gastric Cancer in 1962. The latest 15th edition was published in 2017. One of its main features is that lymph nodes are numbered as stations. The number of groups has increased from 16 to 36 in 55 years. Seven groups (nos. 1, 2, 5, 7, 9, 10, and 15) were retained from the original classification. Nine groups (nos. 3, 4, 6, 8, 11, 12, 13, 14, and 16) were sub-divided into two or more groups. Furthermore, seven groups (nos. 17, 18, 19, 20, 110, 111, and 112) were added in the 6th, 11th, and 12th editions. This numbering system helps surgeons recognize the exact lymph nodes that need to be dissected. However, the numbering system has become extremely complicated. It is necessary to organize the historical background of each lymph node station and share the definitions clearly. This review focuses on nine anatomical zones around the stomach and summarizes the history of lymph node stations in the Japanese Classification of Gastric Carcinoma. Lymph node stations will continue to be modified in the future, and the historical background may be useful in future revisions.

Potential advantages of robotic total gastrectomy for gastric cancer: a retrospective comparative cohort study.

Laparoscopic total gastrectomy (LTG) is a highly technical surgery that can lead to postoperative complications. Whether the recently introduced robotic surgery overcomes the drawbacks of laparoscopic surgery in total gastrectomy remains controversial. Therefore, we aimed to elucidate the potential benefits of robotic total gastrectomy (RTG) and compare the short-term outcomes of RTG and LTG. We retrospectively analyzed 56 patients with primary gastric or esophagogastric junction cancer who underwent RTG or LTG between June 2017 and July 2021. The groups were compared in terms of operative outcomes and postoperative complications. Potential risk factors associated with postoperative complications were assessed by performing multivariable analysis using logistic regression models via the exact method. Operation time was significantly longer, and postoperative hospital stay was significantly shorter in the robotic group (550 vs. 466 min, P < 0.001; 13 vs. 18 days, P = 0.013, respectively). The incidence of overall postoperative complications of Clavien-Dindo grade ≥ II was 18.5% and 24.1% in the RTG and LTG groups, respectively. Pancreatic fistulas were not observed, but other local complications were observed in 0% and 17.2% of the RTG and LTG groups, respectively (P = 0.052). In the multivariable analysis, the independent risk factors for local complications were laparoscopic surgery (odds ratio [95% confidence interval] 8.542 [1.065-∞], P = 0.045) and esophagogastric junction cancer (16.646 [2.559-∞], P = 0.005). Compared with LTG, RTG was associated with fewer local complications (mainly anastomotic leakage), especially in cases of esophagogastric junction cancer with high anastomotic sites.

Automated segmentation by deep learning of loose connective tissue fibers to define safe dissection planes in robot-assisted gastrectomy.

The prediction of anatomical structures within the surgical field by artificial intelligence (AI) is expected to support surgeons' experience and cognitive skills. We aimed to develop a deep-learning model to automatically segment loose connective tissue fibers (LCTFs) that define a safe dissection plane. The annotation was performed on video frames capturing a robot-assisted gastrectomy performed by trained surgeons. A deep-learning model based on U-net was developed to output segmentation results. Twenty randomly sampled frames were provided to evaluate model performance by comparing Recall and F1/Dice scores with a ground truth and with a two-item questionnaire on sensitivity and misrecognition that was completed by 20 surgeons. The model produced high Recall scores (mean 0.606, maximum 0.861). Mean F1/Dice scores reached 0.549 (range 0.335-0.691), showing acceptable spatial overlap of the objects. Surgeon evaluators gave a mean sensitivity score of 3.52 (with 88.0% assigning the highest score of 4; range 2.45-3.95). The mean misrecognition score was a low 0.14 (range 0-0.7), indicating very few acknowledged over-detection failures. Thus, AI can be trained to predict fine, difficult-to-discern anatomical structures at a level convincing to expert surgeons. This technology may help reduce adverse events by determining safe dissection planes.

A case of ectopic pancreas of the stomach accompanied by intraductal papillary mucinous neoplasm with GNAS mutation.

BACKGROUND: Ectopic pancreas is basically a benign disease and is not always necessary to be removed. However, all types of neoplasms occurring in the normal pancreas such as ductal adenocarcinomas and intraductal papillary mucinous neoplasms (IPMNs) may develop even within ectopic pancreas. We recently encountered an extremely rare case of ectopic pancreas in the gastric antrum associated with IPMN possessing a GNAS mutation. CASE PRESENTATION: A 71-year-old Japanese woman complained of epigastric pain. Computed tomography and upper gastrointestinal endoscopy showed an intramural cystic mass in the antrum of the stomach. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) biopsy did not give a definitive diagnosis, and the patient underwent resection of the lesion. Histology of the resected specimen showed that the gastric intramural lesion was ectopic pancreas. Moreover, the lesion contained dilated duct components with tubulo-villous epithelial proliferation consistent with pancreatic IPMN. Since the covering epithelial cells had highly atypical nuclei, the lesion was diagnosed as IPMN with high grade dysplasia. Immunohistochemistry showed that the IPMN component showed to be MUC2-, MUC5AC-, and CDX2-positive but MUC1- and MUC6-negative. Mutational analyses using genomic DNA revealed that the IPMN component had a mutation of GNAS at exon 8 (Arg201Cys). CONCLUSION: We finally diagnosed this case as gastric ectopic pancreas accompanied by intestinal type IPMN with high grade dysplasia possessing GNAS mutation. Although there were 17 cases of ectopic pancreas with IPMN including 6 cases of gastric ones reported in the English literature, this is the first case of ectopic pancreas with IPMN which was proved to have GNAS mutation. Intimate preoperative examinations including imaging analyses and EUS-FNA biopsy/cytology are recommended to decide whether the lesion has to be resected or not even if they are not effective for getting the right diagnosis.

Successful revision surgery for very late-onset stomal obstruction following Gomez gastroplasty: a case report.

BACKGROUND: Gomez gastroplasty, which was developed in the 1970s as one of the gastric restrictive surgeries for severe obesity, partitions the stomach using a stapler from the lesser towards the greater curvature at the upper gastric body, leaving a small channel. This procedure is no longer performed due to poor outcomes, but surgeons can encounter late-onset complications even decades after the surgery. Here, we report a case of very late-onset stomal obstruction following Gomez gastroplasty which was successfully treated by revision surgery. CASE PRESENTATION: A 58-year-old man was referred to our institution with sudden-onset nausea and vomiting. He underwent weight loss surgery in the USA in 1979, but the details of the surgery were unclear. Esophagogastroduodenoscopy demonstrated a stoma at the greater curvature of the upper gastric body, and fluoroscopy showed retention of contrast medium in the fundus and poor outflow through the stoma. Abdominal computed tomography revealed a staple line partitioning the stomach. Considering these preoperative investigation findings and the period during which the surgery was performed, the patient was diagnosed with very late-onset stomal obstruction following Gomez gastroplasty. Supporting the preoperative diagnosis, the surgical findings revealed a staple line extending from the lesser towards the greater curvature of the upper gastric body and a channel reinforced by a running seromuscular suture on the greater curvature. Moreover, gastric torsion caused by the enlarged proximal gastric pouch was found. Re-gastroplasty involving wedge resection of the original channel was performed followed by construction of a new channel. Postoperative course was uneventful, and the patient no longer had symptoms of stomal obstruction after revision surgery. CONCLUSIONS: Re-gastroplasty was safe and feasible for very late-onset stomal obstruction following Gomez gastroplasty. Accurate preoperative diagnosis based on the patient's interview and the investigation findings was important for surgical planning. A careful follow-up is required to prevent excessive weight regain after revision surgery.

Robot-assisted Valvuloplastic Esophagogastrostomy by Double-flap Technique Using a Knifeless Linear Stapler After Proximal Gastrectomy.

After proximal gastrectomy, valvuloplastic esophagogastrostomy by double-flap technique could be the ideal reconstruction to prevent gastroesophageal reflux. However, it is demanding procedure in laparoscopic surgery. In this video, we demonstrate a robot-assisted double-flap technique using a knifeless stapler.

Accuracy of Preoperative Endoscopy in Determining Tumor Location Required for Surgical Planning for Esophagogastric Junction Cancer.

PURPOSE: The surgical strategy for esophagogastric junction (EGJ) cancer depends on the tumor location as measured relative to the EGJ line. The purpose of this study was to clarify the accuracy of diagnostic endoscopy in different clinicopathological backgrounds. METHODS: Subjects were 74 consecutive patients with abdominal esophagus to upper gastric cancer who underwent surgical resection. Image-enhanced endoscopy with narrow-band imaging (NBI) was used to determine the EGJ line, prioritizing the presence of palisade vessels, followed by the upper end of gastric folds, as a landmark. The relative positional relationship between the tumor epicenter and the EGJ line was classified into six categories, and the agreement between endoscopic and pathologic diagnoses was examined to evaluate prediction accuracy. RESULTS: The concordance rate of 69 eligible cases was 87% with a kappa coefficient (K) of 0.81. The palisade vessels were observed in 62/69 patients (89.9%). Of the 37 pathological EGJ cancers centered within 2 cm above and below the EGJ line, Barrett's esophagus was found to be a significant risk factor for discordance (risk ratio, 4.40; p = 0.042); the concordance rate of 60% (K = 0.50) in the Barrett's esophagus group was lower than the rate of 91% (K = 0.84) in the non-Barrett's esophagus group. In five of six discordant cases, the EGJ line was estimated to be proximal to the actual line. CONCLUSION: Diagnostic endoscopy is beneficial for estimating the location of EGJ cancer, with a risk of underestimating esophageal invasion length in patients with Barrett's esophagus.

Anastomotic leakage after esophagectomy possibly caused by compression of the gastric conduit behind the sternoclavicular joint: a report of three cases.

BACKGROUND: The narrowness of the thoracic inlet is often a problem in retrosternal reconstruction after esophagectomy. We report here three cases in which compression of the gastric conduit behind the sternoclavicular joint possibly caused anastomotic leakage. CASE PRESENTATIONS: The first case was a 71-year-old man who underwent subtotal esophagectomy for upper esophageal cancer followed by retrosternal reconstruction. On postoperative day 2, he developed septic shock and underwent reoperation because of a necrotic gastric conduit. The tip of the conduit above the manubrium was necrotic due to strangulation as a result of compression by the sternoclavicular joint. The second and third cases were a 50-year-old woman and a 71-year-old man who underwent subtotal esophagectomy for middle and lower esophageal cancer, respectively, followed by retrosternal reconstruction. Despite indocyanine green fluorescence imaging indicating adequate blood flow in both cases, the tip of the conduit appeared pale and congested because of compression by the sternoclavicular joint after anastomosis. Postoperatively, these two patients developed anastomotic leakage that was confirmed endoscopically on the ventral side of the gastric wall that had been pale intraoperatively. CONCLUSIONS: When performing reconstruction using the retrosternal route after esophagectomy, it is important to ensure that compression by the sternoclavicular joint does not have an adverse impact on blood flow at the tip of the gastric conduit.

Pathological Complete Response and Successful Conversion Surgery After Nivolumab Therapy for Stage IV Oesophagogastric Junction Cancer.

BACKGROUND: Multimodality treatment including immune check point inhibitors is required for stage IV oesophagogastric junction cancer (OGJC). CASE REPORT: A 69-year-old man, was diagnosed with advanced OGJC and para-aortic lymph node metastasis (T3N+M1, stage IV), which upon biopsy, was shown to be an adenocarcinoma. After eight courses of nivolumab as third-line chemotherapy, the primary tumour and enlarged regional and para-aortic lymph nodes shrunk markedly, while tumour markers decreased within normal ranges. We performed a minimally invasive Ivor-Lewis oesophagectomy with completion of an abdominal D2 and transhiatal lower mediastinal lymph node dissection. Pathological findings revealed a complete response for the primary tumour and a regional lymph node metastasis. A biopsy of the previous sample revealed microsatellite instability-negativity, Epstein-Barr virus-negativity, and programmed cell death-1-ligand combined positive score of 2. He was followed up for 3 months without recurrence. CONCLUSION: Nivolumab may induce pathological complete response for stage IV OGJC even in cases negative for microsatellite instability and Epstein-Barr virus, besides the programmed cell death-1-ligand combined positive score of <5.

Pathological Complete Remission of Liver Metastases Correlates With Elimination of Tumor-infiltrating Tregs in Gastric Cancer.

BACKGROUND/AIM: Tumor-infiltrating Foxp3+ regulatory T-cells (Ti-Tregs) promote tumor progression and contribute to poor prognosis in gastric cancer, but the relationship between Ti-Tregs and response to chemotherapy for liver metastases from gastric cancer (LMGC) is unclear. We estimated the correlation between pathological response to chemotherapy and Ti-Tregs in LMGC. PATIENTS AND METHODS: Ti-Tregs were analyzed with immunohistochemistry as CD3+ Foxp3+ cells in patients with synchronous LMGC. RESULTS: Of 53 patients with LMGC, 49 received chemotherapy as initial treatment and 10 underwent R0 resection. LMGC disappeared pathologically in 5 resected cases despite radiologically residual disease. Ti-Tregs were found frequently in residual LMGC and primary lesions but rarely in tumor scar tissue. There was no relationship between frequency of CD8+ cells and pathological response. CONCLUSION: Marked reduction in Ti-Tregs correlates with pathological complete remission of LMGC. Ti-Tregs may be a biomarker to predict the effects of chemotherapy when used in combination with radiological findings.

Clinical outcomes of proximal gastrectomy for gastric cancer: A comparison between the double-flap technique and jejunal interposition.

BACKGROUND: The optimal reconstruction method after proximal gastrectomy (PG) has been debatable. Recent reports have shown that the double-flap technique (DFT) provides good outcomes in terms of postoperative nutritional status and quality of life. However, no study has compared the clinical outcomes of the DFT with other reconstruction methods. Here, we evaluated and compared the clinical outcomes between the DFT and jejunal interposition (JI) after PG for gastric cancer. MATERIALS AND METHODS: The medical records of 34 consecutive patients who had undergone PG for upper third gastric cancer between January 2011 and October 2016 were reviewed retrospectively. The main factors investigated were surgical outcomes, postoperative nutritional status, symptoms, and endoscopic findings 1 year after surgery. RESULTS: Thirty-four patients were enrolled (DFT, 14; JI, 20). The operation time was similar between the two techniques (228 and 246 minutes for DFT and JI, respectively, P = 0.377), as were the rates of anastomotic complications (7% and 0% for DFT and JI, respectively, P = 0.412). Body weight loss was significantly lower in the DFT group than in the JI group (-8.1% vs -16.1%, P = 0.001). Total protein and albumin levels were higher in the DFT group than in the JI group (0% vs -2.9%, P = 0.053, and -0.3% vs -6.1%, P = 0.077, respectively). One patient in the DFT group and no patients in the JI group experienced reflux esophagitis (≥ grade B) (P = 0.393). Anastomotic strictures were not observed as postoperative complications in either group. CONCLUSIONS: Surgical outcomes revealed that the DFT was safe and feasible, similar to JI. In terms of controlling postoperative body weight loss, the DFT is a better reconstruction technique than JI after PG.

Anastomosis behind the sternoclavicular joint is associated with increased incidence of anastomotic stenosis in retrosternal reconstruction with a gastric conduit after esophagectomy.

Anastomotic stenosis after esophagectomy is a major cause of long-term morbidity because it leads to poor dietary intake and malnutrition that markedly reduces the quality of life. The aim of this study was to test the hypothesis that anastomosis behind the sternoclavicular (SC) joint in retrosternal reconstruction is associated with an increased risk of anastomotic stenosis compared with anastomosis deviated from the joint. Among 226 patients who underwent esophagectomy for esophageal cancer between April 2010 and March 2019, we selected 114 patients who underwent retrosternal reconstruction using a gastric conduit for this study. They were classified into two groups according to the location of the anastomosis as determined by axial sections on postoperative computed tomography scans: anastomosis located behind the SC joint (Group B; n = 71) and anastomosis deviated from the joint (Group D; n = 43). The primary endpoint was the difference in the incidence of anastomotic stenosis between the two groups. Whether the occurrence of anastomotic leak affected the likelihood of anastomotic stenosis was also investigated. The incidence of anastomotic stenosis was significantly higher in Group B than in Group D (71.8% [n = 51] vs. 18.6% [n = 8]; P < 0.0001). The incidence of stenosis in patients who developed an anastomotic leak was significantly higher in Group B than in Group D (88.0% vs. 41.7%; P = 0.0057), although the findings were similar in patients who did not develop anastomotic leak (63.0% and 9.7%, respectively; P < 0.0001). We conclude that anastomosis located behind the SC joint in retrosternal reconstruction with a gastric conduit after esophagectomy is associated with an increased risk of anastomotic stenosis regardless of the development of anastomotic leak.

Laparoscopic and left thoracoscopic Ivor-Lewis esophagectomy for Siewert type II esophagogastric junction cancer with right aortic arch: a case report.

BACKGROUND: Right aortic arch (RAA) is a congenital malformation detected in 0.04% of the population without heterotaxia and makes esophagectomy and mediastinal lymphadenectomy difficult. A left thoracic approach is recommended in patients with RAA, but a minimally invasive procedure has not yet been established. CASE PRESENTATION: The case was a 40-year-old man with RAA and Siewert type II adenocarcinoma of the esophagogastric junction with metastases to the adrenal glands and paraaortic lymph nodes. Conversion surgery was performed when radiologic disappearance of metastatic disease was confirmed after first-line treatment consisting of 12 cycles of S-1 plus platinum-based systemic chemotherapy. Minimally invasive laparoscopic and left thoracoscopic Ivor-Lewis esophagectomy was performed in the right semi-lateral decubitus position. The esophagus was easy to see on left thoracoscopy because of the RAA. Esophagectomy with lower mediastinal lymphadenectomy and an intrathoracic esophagogastric anastomosis was performed successfully with laparoscopy and thoracoscopy without a position change. There were no surgical complications, and no residual cancer was detected in the resected specimen on pathological examination. There has been no recurrence during 21 months of follow-up. CONCLUSIONS: Laparoscopic and left thoracoscopic Ivor-Lewis esophagectomy in the right semi-lateral decubitus position is a minimally invasive, anatomically novel procedure for Siewert type II esophagogastric junction cancer in patients with RAA.

Endoscopic observation of the palisade vessels in Killian-Jamieson diverticulum was useful for diagnosis and surgical treatment: a case report.

BACKGROUND: Killian-Jamieson diverticulum is a rare pharyngoesophageal diverticulum that arises below the cricopharyngeus muscle. Unlike the most common Zenker's diverticulum, which requires cricopharyngeal and esophageal myotomy, diverticulectomy is sufficient for surgical treatment of Killian-Jamieson diverticulum. Thus, accurate preoperative diagnosis is indispensable for avoiding unnecessarily invasive surgery. Here, we report a case of Killian-Jamieson diverticulum in which endoscopic observation of the palisade vessels was useful for diagnosis and intraoperative endoscopy was effective in guiding surgical resection. CASE PRESENTATION: A 65-year-old woman complained of pharyngeal discomfort and increased coughing and was referred to our hospital with a diagnosis of a pharyngoesophageal diverticulum. Contrast esophagography and cervical computed tomography revealed a diverticulum measuring 3 cm in diameter on the left side of the cervix. The diverticulum was identified by endoscopy just below the palisade vessels, which represents the level of the upper esophageal sphincter, and was diagnosed as Killian-Jamieson diverticulum. She underwent diverticulectomy without cricopharyngeal and esophageal myotomy. After exposing the diverticulum under light from the endoscope and washing out the food residue inside endoscopically, the diverticulum was resected using the endoscope as a bougie so as not to narrow the esophagus. The postoperative course was uneventful, and she remains asymptomatic without recurrence or stenosis at 6 months after surgery. CONCLUSIONS: Endoscopic observation of the palisade vessels in addition to esophagography can help diagnose Killian-Jamieson diverticulum and determine the optimal surgical procedure. Diverticulectomy can be performed intentionally and safely with the aid of intraoperative endoscopy.

True esophagogastric junction adenocarcinoma: background of its definition and current surgical trends.

The definition of true esophagogastric junction (EGJ) adenocarcinoma and its surgical treatment are debatable. We review the basis for the current definition and the Japanese surgical strategy in managing true EGJ adenocarcinoma. The Siewert classification is a well-known anatomical classification system for EGJ adenocarcinomas: type II tumors in the region 1 cm above and 2 cm below the EGJ are described as "true carcinoma of the cardia". Coincidentally, this range matches gastric cardiac gland distribution. Conversely, Nishi's classification is generally used to describe EGJ carcinomas, defined as tumors with the center located within 2 cm above and 2 cm below the EGJ, regardless of their histological subtype. This range coincides with the extent of the lower esophageal sphincter combined with gastric cardiac gland distribution. The current Japanese surgical strategy focuses on the tumor range from the EGJ to the esophagus and stomach. According to previous studies, the strategy can be roughly classified into three types. The optimal surgical procedure for true EGJ adenocarcinoma is controversial. However, an ongoing Japanese nationwide prospective trial will help confirm the appropriate standard surgery, including the optimal extent of lymph node dissection.

Laparoscopic Suprapancreatic Lymph Node Dissection Using a Systematic Mesogastric Excision Concept for Gastric Cancer.

BACKGROUND: Gastrointestinal cancer surgery requires en bloc removal of the primary tumor and organ-specific mesentery1,2. However, this surgical concept for gastric cancer has not yet been applied because of the morphological complexity of the mesenteries of the stomach. Lymph node dissection in gastric cancer surgery can be roughly performed into three regions: lesser curvature, grater curvature, and suprapancreatic region. In this video, we introduced laparoscopic lymphadenectomy in the suprapancreatic region using a systematic mesogastric excision (SME), which has been reported as a concept to perform en bloc resection3. METHODS: This procedure was divided into three steps. First, mesenterization of the mesogastrium was performed by dissecting the embryological planes, and the mesogastrium was dissected from the retroperitoneal surface (Fig. 1a). Second, soft tissue, including the lymph node, was separated from the pancreas and the splenic artery by tracing the inner dissectable layer (Fig. 1b). Finally, the tumor-specific mesentery was transected according to the extent of the lymphadenectomy (Fig. 1c).Fig. 1Intraoperative findings during the stepwise procedure in dissecting the lymph node in the suprapancreatic region. The red broken line indicates the surgical outline. a The mesogastrium is dissected from the retroperitoneal tissue. b The mesogastrium is separated from the pancreas and splenic artery. c The mesogastric transection line is determined on the basis of the extent of the lymphadenectomy. Inf. phrenic a. inferior phrenic artery; PGA posterior gastric artery; Post. epiploic a. posterior epiploic artery; RV renal vein; SA splenic artery; SV splenic vein RESULTS: Between January 2017 and December 2017, six patients underwent laparoscopic distal gastrectomy with D2 lymphadenectomy using SME. The median time required to complete the suprapancreatic lymphadenectomy was 48 min. No patient underwent conversion to open surgery or experienced intraoperative complications. CONCLUSIONS: We believe that this laparoscopic suprapancreatic lymphadenectomy using SME takes advantage of the surgical anatomy and achieves en bloc removal of the primary tumor and gastric mesentery. This series is a proof of concept that this procedure can be performed in a timely manner and is feasible.

Creation of Virtual Three-Dimensional Animation Using Computer Graphic Technology for Videoscopic Transcervical Upper Mediastinal Esophageal Dissection.

Background: Videoscopic transcervical mediastinal lymphadenectomy has been attempted to reduce thoracotomy-related complications of surgical treatment for esophageal cancer. However, many surgeons would hesitate to attempt this procedure because of the difficulty in understanding the anatomical orientation. In this study, we aimed to create a three-dimensional computer graphic (3D CG) animation and compare it with the real-life operation. Materials and Methods: LightWave 3D® version 7 was used as a rendering software to create the 3D CG. The 3D CG images were superimposed to generate an animation using AfterEffects CC®. Results: The 3D CG animation for videoscopic transcervical upper mediastinal esophageal dissection was successfully created; it dynamically shows the scene, especially the separation between the esophagus and trachea, and enables surgeons to easily understand the anatomical orientation when using transcervical approach. This 3D CG animation was of high quality and similar to the real-life operation. Conclusions: We created a virtual 3D CG animation for the transcervical approach, which will contribute to understanding this procedure for esophageal cancer preoperatively.