Robotic spleen‑preserving suprapancreatic and splenic hilar lymph node dissection using the preemptive retropancreatic approach in total gastrectomy for gastric cancer

Advanced gastric cancer that has not invaded the greater curvature is a good indication for total gastrectomy (TG) with spleen-preserving suprapancreatic and splenic hilar lymph node dissection (LND). However, the suprapancreatic and splenic hilar LND increases the area of dissection of the pancreas, and prolonged pressure drainage of the pancreas is required to maintain a clear operative view. This can lead to an increased risk of postoperative pancreatic complications. To report the efficacy of our novel preemptive retropancreatic approach (PRA) for the suprapancreatic and splenic hilar LND in robotic TG (RTG). We report our experience with nine patients with gastric cancer who underwent spleen-preserving splenic hilar LND using PRA during RTG at Hokkaido University from October 2018 to November 2021. The PRA involves initial dissection of the left side of the retropancreatic space, followed by the release of the adherence between the retroperitoneum surface and the pancreas (fusion fascia), which provides a good operative field and prevents contact with the pancreas during the suprapancreatic and splenic hilar LND in RTG. The median operating time was 488 min (254-564 min). The median intraoperative bleeding was 55 mL (0-115 mL). One patient had postoperative complications (above grade II of the Clavien-Dindo classification), but there were no postoperative pancreatic complications. The spleen-preserving suprapancreatic and splenic hilar LND using PRA could help to reduce the postoperative pancreatic complications associated with RTG.Trial registration number and date of registration The Hokkaido University Hospital institutional review board approved the data collection and analysis. The trial registration number and date of registration are No. 021-0022 and July 26, retrospectively registered.

Aldehyde Dehydrogenese-1 High Cancer Stem-like Cells/Cancer-initiating Cells Escape from Cytotoxic T Lymphocytes due to Lower Expression of Human Leukocyte Antigen Class 1

BACKGROUND/AIM

Human gastric cancer stem-like cells (CSCs)/cancer-initiating cells can be identified as aldehyde dehydrogenase-high (ALDHhigh) cells. Cancer immunotherapy employing immune checkpoint blockade has been approved for advanced gastric cancer cases. However, the effectiveness of cancer immunotherapy against gastric CSCs/CICs remains unclear. This study aimed to investigate the susceptibility of gastric CSCs/CICs to immunotherapy.

MATERIALS AND METHODS

Gastric CSCs/CICs were isolated as ALDHhigh cells using the human gastric cancer cell line, MKN-45. ALDHhigh clone cells and ALDHlow clone cells were isolated using the ALDEFLUOR assay. ALDH1A1 expression was assessed via qRT-PCR. Sphere-forming ability was evaluated to confirm the presence of CSCs/CICs. A model neoantigen, AP2S1, was over-expressed in ALDHhigh clone cells and ALDHlow clone cells, and susceptibility to AP2S1-specific TCR-T cells was assessed using IFNγ ELISPOT assay.

RESULTS

Three ALDHhigh clone cells were isolated from MKN-45 cells. ALDHhigh clone cells exhibited a stable phenotype in in vitro culture for more than 2 months. The High-36 clone cells demonstrated the highest sphere-forming ability, whereas the Low-8 cells showed the lowest sphere-forming ability. High-36 cells exhibited lower expression of HLA-A24 compared to Low-8 cells. TCR-T cells specific for AP2S1 showed lower reactivity to High-36 cells compared to Low-8 cells.

CONCLUSION

High-36 cells and Low-8 cells represent novel gastric CSCs/CICs and non-CSCs/CICs, respectively. ALDHhigh CSCs/CICs evade T cells due to lower expression of HLA class 1.

Impact of Neutrophil Extracellular Traps Identified by Citrullinated Histone H3 Immunohistochemistry for Postoperative Prognosis in Patients with Extrahepatic Cholangiocarcinomas

BACKGROUND

Neutrophil extracellular traps (NETs) are extracellular chromatin structures composed of cytoplasmic, granular, and nuclear components of neutrophils. Recently, NETs have received much attention for their role in tumor biology; however, their impact on the postoperative prognosis of patients with extrahepatic cholangiocarcinomas (EHCCs) remains unclear. The purpose of this study was to clarify the impact of NETs identified by immunohistochemical citrullinated histone H3 (Cit-H3) staining on postoperative overall survival (OS) in patients with perihilar cholangiocarcinoma (PHCC) and distal cholangiocarcinoma (DCC).

METHODS

This study included 318 patients with EHCC (PHCC, n = 192; DCC, n = 126) who underwent surgical resection with curative intent. Neutrophils and NETs were identified by immunohistochemistry using antibodies against CD15 and Cit-H3, respectively. Based on the distribution of CD15 and Cit-H3 expression in the tumor bed, the patients were classified into four groups: one negative group and three subgroups of the positive group (diffuse, intermediate, and focal subgroups).

RESULTS

No significant difference was found in the postoperative OS rate depending on the distribution of CD15 expression in patients with PHCC or DCC. However, the three subgroups with positive Cit-H3 expression had significantly poorer OS than the negative group for both PHCC and DCC. Moreover, positive Cit-H3 was an independent OS factor in the multivariable analyses of PHCC (hazard ratio [HR] 1.69, 95% confidence interval [CI] 1.11-2.59, P = 0.0115) and DCC (HR 2.03; 95% CI 1.21-3.42, P = 0.0057).

CONCLUSIONS

The presence of NETs in the tumor microenvironment may have adverse prognostic effects in patients with EHCCs.

Incidence of atrial fibrillation after esophageal cancer surgery with L-carnitine use: a preliminary single-group interventional study

PURPOSE

We aimed to investigate the POAF rate and blood FABP4 levels after perioperative L-carnitine administration in patients with esophageal cancer.

METHODS

L-carnitine (3 g in three divided doses) was administered to 15 patients 2 days before and 3 days after surgery. POAF during the study period and blood FABP4 levels (ELISA) before and after L-carnitine administration were evaluated. Accurate 95% confidence intervals (CI) for POAF incidence and changes in blood FABP4 levels were calculated. The preoperative predicted POAF rate was calculated using an application for esophageal cancer. The correlation between FABP4 levels and the predicted POAF rate was analyzed using Pearson's coefficient (r).

RESULTS

Thirteen patients completed this study. The predicted POAF rate was 24% (17%, 34%) (median; interquartile range). The actual incidence of POAF was 7.7% (95% CI: 0.2-36%). Blood FABP4 levels changed from 10.3 to 7.0 ng/mL; the average change was - 3.3 (95% CI: - 6.6 to - 0.1). A positive correlation was found between preoperative FABP4 levels and the predicted POAF rates (r = 0.564).

CONCLUSIONS

The POAF rate after esophageal surgery was 7.7% for L-carnitine. L-carnitine may reduce blood FABP4 levels. This preliminary study will contribute to the planning of sample sizes in future randomized trials.

Tele-robotic distal gastrectomy with lymph node dissection on a cadaver

The purpose of this study is to evaluate the performance of tele-robotic distal gastrectomy (tele-RDG) with lymph node dissection (LND) using a novel Japanese-made surgical robot hinotori™ (Medicaroid, Kobe, Japan) in a cadaver with a presumptive gastric cancer. The Cadaveric Anatomy and Surgical Training Laboratory (CAST-Lab.) at Hokkaido University and Kushiro City General Hospital (KCGH) are connected by a guaranteed type line (1 Gbps), and the distance between the two facilities is 250 km. A patient cart was installed at CAST-Lab, and a surgeon cockpit was installed at KCGH. Tele-RDG with D2 LND was performed on an adult human cadaver. In all surgical processes, the communication environment was stable without image degradation, and the mean round trip time was 40 milliseconds (36.5-55 milliseconds). For tele-RDG with D2 LND, the operation time was 199 minutes without any technical problems. Tele-RDG using hinotori™ was feasible and similar to local robotic RDG.

Robot-assisted laparoscopic total gastrectomy for gastric cancer with common hepatic artery passed behind the portal vein: A case report

INTRODUCTION

It is essential to identify variations of celiac artery (CA) and common hepatic artery (CHA), using preoperative computed tomography (CT) imaging, for safe gastrectomy and lymph node dissection in gastric cancer (GC) surgery. We report a relatively rare case with the CHA passing behind the portal vein (PV), in which we performed robot-assisted total gastrectomy (RTG) after chemotherapy as conversion surgery.

CASE PRESENTATION

A 78-year-old man with GC was referred for conversion surgery. Three-dimensional CT angiography revealed an anomalous CHA passing behind the PV. The anomaly corresponded to type I according to Adachi's classification, and the patient underwent robot-assisted laparoscopic total gastrectomy D2 lymphadenectomy (RTG D2) with Roux-en-Y reconstruction. The operation time was 543 min, blood loss was 115 ml, and no intraoperative complications occurred. The postoperative course was uneventful.

CLINICAL DISCUSSION

A word of caution during the surgical procedure entails the manipulation of the suprapancreatic lymph node dissection. Initially, it is crucial to identify the anterior surface of the portal vein (PV) and the nerve plexus surrounding the common hepatic artery (CHA). After completely dissecting the entire circumference, the PV is secured using vascular tape. By gently pulling the vascular tape towards the ventral aspect, a safe execution of lymph node dissection no.8 and 12 on the dorsal side of the PV can be accomplished. Meticulous handling of the anatomical abnormalities observed in the preoperative images may prevent unintended hemorrhage.

CONCLUSION

We report a case with vascular anomalies in which RTG D2 was performed successfully as a conversion surgery.

Surgical skills assessment of pancreaticojejunostomy using a simulator may predict patient outcomes: A multicenter prospective observational study

BACKGROUND

Pancreatoduodenectomy, an advanced surgical procedure with a high complication rate, requires surgical skill in performing pancreaticojejunostomy, which correlates with operative outcomes. We aimed to analyze the correlation between pancreaticojejunostomy assessment conducted in a simulator environment and the operating room and patient clinical outcomes.

METHODS

We recruited 30 surgeons (with different experience levels in pancreatoduodenectomy) from 11 institutes. Three trained blinded raters assessed the videos of the pancreaticojejunostomy procedure performed in the operating room using a simulator according to an objective structured assessment of technical skill and a newly developed pancreaticojejunostomy assessment scale. The correlations between the assessment score of the pancreaticojejunostomy performed in the operating room and using the simulator and between each assessment score and patient outcomes were calculated. The participants were also surveyed regarding various aspects of the simulator as a training tool.

RESULTS

There was no correlation between the average score of the pancreaticojejunostomy performed in the operating room and that in the simulator environment (r = 0.047). Pancreaticojejunostomy scores using the simulator were significantly lower in patients with postoperative pancreatic fistula than in those without postoperative pancreatic fistula (P = .05). Multivariate analysis showed that pancreaticojejunostomy assessment scores were independent factors in postoperative pancreatic fistula (P = .09). The participants highly rated the simulator and considered that it had the potential to be used for training.

CONCLUSION

There was no correlation between pancreaticojejunostomy surgical performance in the operating room and the simulation environment. Surgical skills evaluated in the simulation setting could predict patient surgical outcomes.

Identification of antibody against wingless‑type MMTV integration site family member 7B as a biliary cancer tumor marker

Biliary cancer has a poor prognosis due to a lack of specific biomarkers and difficulty in diagnosis. The present study aimed to identify serum tumor markers for the diagnosis of biliary cancer via serological identification of antigens by recombinant cDNA expression cloning. Wingless‑type MMTV integration site family, member 7 (WNT7B) was identified as a target antigen, suggesting the presence of serum antibodies against this antigen. Deletion mutants were then prepared to evaluate the response to serum antibodies. When serum antibody levels against WNT7B deletion mutants (WNT7B_-92‑2, _-92‑260, _2-260 and _184-260) were examined using amplified luminescence proximity homogeneous assay‑linked immunosorbent assay, the levels of the antibody against WNT7B with amino acids 184‑260 were higher in patients with biliary cancer than in healthy donors. Therefore, the region covering residues 184‑260 of WNT7B was decomposed to generate seven peptides, and the levels of antibodies against these peptides were measured. Among them, the levels of antibodies against WNT7B_234‑253 and WNT7B_244‑260 were higher in patients with biliary cancers than in healthy donors (WNT7B_234‑253, P=0.0009; WNT7B_244‑260, P=0.0005). The levels of the antibody against the former were specifically high in patients with biliary cancer but not in those with esophageal, gastric, colorectal, pancreatic, or breast cancer. Furthermore, analysis by the cutoff value of WNT7B_234‑253 defined by ROC showed a high sensitivity of 70% in patients with biliary cancer. Therefore, the serum levels of the antibody against WNT7B_234‑253 may be useful as a marker for biliary cancer diagnosis.

Predictors of Long-Term Survival in Pancreatic Ductal Adenocarcinoma after Pancreatectomy: TP53 and SMAD4 Mutation Scoring in Combination with CA19-9

BACKGROUND

Pancreatic ductal adenocarcinoma (PDA) is a fatal cancer for which even unfavorable clinicopathological factors occasionally fail to preclude long-term survival. We sought to establish a scoring system that utilizes measurable pre-intervention factors for predicting survival following surgical resection.

METHODS

We retrospectively analyzed 34 patients who died from short-term recurrences and 32 long-term survivors among 310 consecutively resected patients with PDA. A logistic regression model was used to define factors related to clinical parameters, molecular profiles of 18 pancreatic cancer-associated genes, and aberrant expression of major tumor suppressors.

RESULTS

Carbohydrate antigen 19-9 (CA19-9) had the best ability to classify patients with short-term recurrence and long-term survivors [odds ratio 21.04, 95% confidence interval (CI) 4.612-96.019], followed by SMAD4 and TP53 mutation scoring (odds ratio 41.322, 95% CI 3.156-541.035). Missense TP53 mutations were strongly associated with the nuclear expression of p53, whereas truncating mutations were associated with the absence of nuclear p53. The former subset was associated with a worse prognosis. The combination of aberrant SMAD4 and mutation types of TP53 exhibited a better resolution for distinguishing patients with short-term recurrences from long-term survivors (compared with the assessment of the number of mutated KRAS, CDKN2A, TP53, and SMAD4 genes). Calibration of mutation scores combined with CA19-9 in a logistic regression model setting demonstrated a practical effect in classifying long survivors and patients with early recurrence (c-statistic = 0.876).

CONCLUSIONS

Genetic information, i.e., TP53 mutation types and SMAD4 abnormalities, combined with CA19-9, will be a valuable tool for improving surgical strategies for pancreatic cancer.

Assessment of reports on cadaver surgical training (CST) implementation in Japan: current status and challenges

The contents and conflicts of interest of Cadaver Surgical Training (CST) programs in Japan were reported to the Japan Surgical Society CST Promotion Committee based on professional autonomy. After receiving the reports from participating universities, the committee evaluated the validity of these reports and provided advice on the proper implementation of CST. Over the past decade, 38 universities have been using cadavers for clinical education and research, such as CST. If inappropriate entries or unclear areas were identified, the universities could be asked to resubmit their report. This review clarifies the evaluation points of the CST reporting system, shows the status and problems of its reporting, and provides suggestions for the dissemination of CST in the future.

Targeted amplicon sequencing for primary tumors and matched lymph node metastases in patients with extrahepatic cholangiocarcinoma

BACKGROUND

Lymph node metastasis (LNM) is one of the most adverse prognostic factors in extrahepatic cholangiocarcinoma (EHCC) cases. As next-generation sequencing technology has become more widely available, the genomic profile of biliary tract carcinoma has been clarified. However, whether LNMs have additional genomic alterations in patients with EHCC has not been investigated. Here, we aimed to compare the genomic alterations between primary tumors and matched LNMs in patients with EHCC.

METHODS

Sixteen patients with node-positive EHCCs were included. Genomic DNA was extracted from tissue samples of primary tumors and matched LNMs. Targeted amplicon sequencing of 160 cancer-related genes was performed.

RESULTS

Among the 32 tumor samples from 16 patients, 91 genomic mutations were identified. Genomic mutations were noted in 31 genes, including TP53, MAP3K1, SMAD4, APC, and ARID1A. TP53 mutations were most frequently observed (12/32; 37.5%). Genomic mutation profiles were highly concordant between primary tumors and matched LNMs (13/16; 81.3%), and an additional genomic mutation of CDK12 was observed in only one patient.

CONCLUSION

Genomic mutations were highly concordant between primary tumors and matched LNMs, suggesting that genotyping of archived primary tumor samples may help predict genomic mutations of metastatic tumors in patients with EHCC.

Guidelines for cadaver dissection in education and research of clinical medicine (The Japan Surgical Society and The Japanese Association of Anatomists)

This article translates the guidelines for cadaver surgical training (CST) published in 2012 by Japan Surgical Society (JSS) and Japanese Association of Anatomists from Japanese to English. These guidelines are based on Japanese laws and enable the usage of donated cadavers for CST and clinical research. The following are the conditions to implement the activities outlined in the guidelines. The aim is to improve medicine and to contribute to social welfare. Activities should only be carried out at medical or dental universities under the centralized control by the department of anatomy under the regulation of Japanese law. Upon the usage of cadavers, registered donors must provide a written informed-consent for their body to be used for CST and other activities of clinical medicine. Commercial use of cadavers and profit-based CST is strongly prohibited. Moreover, all the cadaver-related activities except for the commercial-based ones require the approval of the University's Institutional Review Board (IRB) before implementation. The expert committee organized at each university for the implementation of CST should summarize the implementation of the program and report the details of the training program, operating costs, and conflicts of interest to the CST Promotion Committee of JSS.

Usage of cadavers in surgical training and research in Japan over the past decade

The “Guidelines for Cadaver Dissection in Education and Research of Clinical Medicine” drafted by the Japan Surgical Society (JSS) and the Japanese Association of Anatomists in 2012 helped dispel legal concerns over cadaver surgical training (CST) and the usage of donated human bodies for research and development (R&D) in the country. Subsequently, in the fiscal year 2018, the Ministry of Health, Labour and Welfare increased the funding for CST, prompting its wider implementation. This study analyzed data obtained in 2012–2021 through the reporting system of the JSS-CST Promotion Committee to map the usage of cadavers for clinical purposes, specifically education and R&D, in Japan. We found that the number of medical universities using cadavers for CST and R&D programs was just 5 in 2012, and it reached 38 for the decade. Thus, about half of Japan’s medical universities implemented such programs over the period. Meanwhile, the total number of programs was 1,173. In the clinical field, the highest number of programs were implemented in orthopedics (27%), followed by surgery (21%), and neurosurgery (12%). Based on the purpose, the most common objective of the programs (approximately 70%) was acquiring advanced surgical techniques. Further, the highest number of programs and participants were recorded in 2019 (295 programs, 6,537 participants). Thus, the guidelines helped expand cadaver usage for clinical purposes in Japan. To further promote the clinical usage of cadavers in medical and dental universities throughout Japan, sharing know-how on operating cadaver laboratories and building understanding among the general public is recommended.

Outcomes of laparoscopic total gastrectomy in elderly patients: a propensity score matching analysis

PURPOSE

This study evaluated the short-term outcomes and prognosis after laparoscopic total gastrectomy (LTG) in elderly patients aged ≥ 80 years in a multicenter retrospective cohort study using propensity score matching.

METHODS

We retrospectively enrolled 440 patients who underwent curative LTG for gastric cancer at six institutions between January 2004 and December 2018. Patients were categorized into an elderly patient group (EG; age ≥ 80 years) and non-elderly patient group (non-EG; age < 80 years). Patients were matched using the following propensity score covariates: sex, body mass index, American Society of Anesthesiologists physical status, extent of lymph node dissection, and Japanese Classification of Gastric Carcinoma stage. Short-term outcomes and prognoses were compared.

RESULTS

We identified 37 propensity score-matched pairs. The median operative time was significantly shorter, and postoperative stay was longer in the EG. In terms of postoperative outcomes, the rates of all complications were comparable. The median follow-up period of the EG and non-EG was 11.5 (1-106.4) months and 35.7 (1-110.0) months, respectively; there were significant differences in 5-year overall survival between the two groups (EG, 58.5% vs. non-EG, 91.5%; P = 0.031). However, there were no significant differences in 5-year disease-specific survival (EG, 62.1% vs. non-EG, 91.5%; P = 0.068) or 5-year disease-free survival (EG, 52.9% vs. non-EG, 60.8%; P = 0.132).

CONCLUSIONS

LTG seems to be safe and feasible in elderly patients. LTG had a limited effect on morbidity, disease recurrence, and survival in elderly patients. Therefore, age should not prevent elderly patients from benefitting from LTG.

Robotic real-time vessel navigation using indocyanine green fluorescence for lymph node dissection along the left gastroepiploic vessels during robotic distal gastrectomy - First experience

Splenic infarction (SI) following gastrectomy is common; severe complications related to SI, such as splenic haemorrhage, abscess formation or rupture, can be fatal. To overcome these problems, we performed real-time vessel navigation using indocyanine green (ICG) fluorescence during robotic distal gastrectomy (RDG). The aim of study is to report the efficacy of robotic real-time vessel navigation for lymph node dissection (LND) along left gastroepiploic vessels (LGEVs). We treated seven patients with gastric cancer who underwent LND along the LGEVs using robotic real-time vessel navigation during RDG at our institution from January 2021 to July 2021. There were no complications (Clavien-Dindo classification II). There were no cases of post-operative SI or spleen-related complications. Robotic real-time vessel navigation using ICG for LND along LGEVs during RDG could help to reduce post-operative spleen-related complications associated with RDG.

A novel laparoscopic near-infrared fluorescence spectrum system with indocyanine green fluorescence overcomes limitations of near-infrared fluorescence image-guided surgery

BACKGROUND

Near-infrared (NIR) fluorescence image-guided surgery (FIGS) introduces a revolutionary new approach to address this basic challenge in minimally invasive surgery. However, current FIGS systems have some limitations - the infrared rays cannot detect and visualise thick tissues with low concentrations of the fluorescent agent. We established a novel laparoscopic fluorescence spectrum (LFS) system using indocyanine green (ICG) fluorescence to overcome these limitations.

MATERIALS AND METHODS

Bovine serum albumin (BSA) was conjugated to ICG, and the mixtures were serially diluted at 5 × 10-8-5 × 10-1 mg/mL. We used the LFS system and a NIR camera system (NLS; SHINKO OPTICAL CO., LTD Tokyo, Japan) to determine the optical dilution for the fluorescence detection. BSA was conjugated to ICG (5.0 × 10-2 mg/mL) and used to coat the clips. We attempted to identify the fluorescence-coated clip from the serosal side of the cadaveric porcine stomach tissues using the LFS system and the NIR camera system. We measured the depth of the cadaveric porcine stomach wall at the thickest part that could be confirmed.

RESULTS

We could not visualise fluorescence concentrations <2.5 × 10-3 mg/mL using the NIR camera system. The spectrum was detected at a concentration <2.5 × 10-3 mg/mL. We were able to identify the spectrum of ICG (829 nm) to a 13-mm depth of cadaveric porcine stomach wall by using the LFS system but could not identify the same with the NIR camera system regardless of wall thickness.

CONCLUSIONS

The novel LFS system with NIR fluorescence imaging in this ex vivo and cadaveric porcine model was confirmed useful at deeper depths and lower concentrations. Based on these findings, we anticipate that the LFS system can be integrated and routinely used in minimally invasive surgery.

Long-term survival after repetitive lymphadenectomy for nodal recurrence of pancreatic neuroendocrine neoplasms: a report of two cases

Pancreatic neuroendocrine neoplasms (PNENs) are rare, but their incidence has increased in recent years. Curative surgery is recommended in several global guidelines for resectable PNENs. Lymph node recurrence after R0 resection for PNENs is infrequent, and global guidelines recommend surgical resection for recurrence, if resectable. However, data on the prognosis after surgical resection for nodal recurrence of PNENs are limited. We herein report two cases in which long-term survival was achieved after repetitive lymphadenectomy for nodal recurrence of PNENs. In both cases, the pathological findings for primary PNEN showed well-differentiated neuroendocrine neoplasms and R0 resection was successfully performed. The Ki-67 index increased with each resection in both cases. Both patients showed long-term survival (10 and 14 years, respectively). Repetitive lymphadenectomy for nodal recurrence of PNENs may improve patient prognosis.

Laparoscopic real-time vessel navigation using indocyanine green fluorescence during laparoscopy-assisted gastric tube reconstruction: First experience

A considerable percentage of morbidity and mortality after oesophagectomy is due to leakage of oesophagogastrostomy, which is mainly caused by ischaemia of the gastric tube. Therefore, we performed laparoscopic real-time vessel navigation (LRTVN) using indocyanine green fluorescence (ICG) during laparoscopy-assisted gastric tube reconstruction (LAGR) to evaluate gastric tube blood flow and avoid vascular injury. This study included five oesophageal cancer patients who underwent video-assisted thoracoscopic oesophagectomy and LAGR. We confirmed the presence of the left gastroepiploic artery (LGEA) in all cases, and no findings such as post-operative gastric tube ischaemia were observed. In all cases, no vascular injury was observed, and the vascularization of LGEA was confirmed. This report is the first to consider the usefulness of LRTVN using ICG during LAGR. LRTVN using ICG during LAGR was considered to be useful for evaluating gastric tube blood flow and avoiding vascular injury around the splenic hiatus.

Effects of preoperative psoas muscle index and body mass index on postoperative outcomes after video-assisted esophagectomy for esophageal cancer

INTRODUCTION

Preoperative psoas muscle index (PMI) and body mass index (BMI) are relevant to postoperative outcomes. We investigated the associations of PMI, BMI, and preoperative nutritional and muscular score with postoperative outcomes in patients with esophageal cancer who underwent video-assisted surgery.

METHODS

We examined 150 patients (124 men, 26 women) who underwent video-assisted esophagectomy from February 2002 to March 2016. We used the Clavien-Dindo (CD) classification to analyze postoperative complications. Because skeletal muscle volume differs significantly between male and female patients, all analyses were performed separately. In male patients, we used the following cut-off values to categorize patients into three groups: PMI = 600 mm² /m² , BMI = 18.5 kg/m² , and preoperative nutritional and muscular (PNM) scores 0 to 2.

RESULTS

Two patients were converted to open thoracotomy. Among male patients, PMI and PNM scores were significant risk factors for complications. Among male patients, in the high PMI group, the number of CD ≥ IIIa complications was significantly lower. In the PNM score 0 group (both PMI and BMI values exceeded the cut-off values), the number of complications was significantly lower. In both genders, PMI and BMI were not significantly associated with survival.

CONCLUSIONS

PMI and PNM scores can be useful for predicting postoperative outcomes in male patients with esophageal cancer having undergone video-assisted surgery.

Short-term outcomes of robotic distal gastrectomy with the "preemptive retropancreatic approach": a propensity score matching analysis

We report the usefulness of the preemptive retropancreatic approach (PRA) in robotic distal gastrectomy (RDG) using multi-jointed forceps. Therefore, this study aimed to compare the short-term outcomes of RDG with PRA and conventional laparoscopic distal gastrectomy using the propensity score matching method. A total of 126 patients [RDG = 55; laparoscopic distal gastrectomy (LDG) = 71] were retrospectively enrolled. Patients were matched using the following propensity score covariates: age, sex, body mass index, American Society of Anesthesiologists physical status, the extent of lymph node dissection, and Japanese Classification of Gastric Carcinoma stage. Surgical results and postoperative outcomes were compared. We identified 28 propensity score-matched pairs. The median operative time and blood loss were comparable (P = 0.272 and P = 0.933, respectively). Regarding postoperative outcomes, the incidence of postoperative complications [Clavien-Dindo classification II (CD ≥ II)] was lower in the RDG group than in the LDG group (P = 0.020). No significant differences in the peak C-reactive protein value and length of hospital stay were observed between the two groups (P = 0.391 and P = 0.057, respectively). In addition, no patients had postoperative pancreas-related complications (≥ CD II) in the RDG group. RDG using PRA seems to be a safe and feasible procedure for gastric cancer because of short-term outcomes and reduction of postoperative complications (especially postoperative pancreas-related complications) as compared to conventional LDG.

Robot-assisted thoracoscopic esophagectomy for gastrointestinal stromal tumor of the esophagus: A case report

Introduction

A gastrointestinal stromal tumor (GIST) often arises in the stomach and small intestine, while esophageal GIST is rare. The first-choice treatment is surgical resection, but there is no standard technique. Herein, we describe our experience in the treatment of esophageal GIST and discuss the usefulness of robotic esophagectomy.

Presentation of case

The patient was a 60-year-old woman, who was diagnosed with a 30 mm GIST in the middle thoracic esophagus. We underwent robot-assisted thoracoscopic esophagectomy in the prone position. The duration of the thoracoscopic part was 69 min and the total operation time was 319 min. Total blood loss was 135 ml. The patient's postoperative course was uneventful after surgery and the patient was discharged home in good condition on the 18th postoperative day.

Discussion

The prognosis of esophageal GIST was less favorable compared with gastric GIST, and due to the anatomical peculiarities of the esophagus, which surgical procedure should be performed is still under debate. Robotic surgery has several technological advantages as it provides a three-dimensional view, ten times magnification, tremor control, and ambidexterity. Therefore, Robotic-assisted minimally invasive esophagectomy (RAMIE) allows achieving for safe R0 resection of esophageal GIST.

Conclusion

RAMIE may be useful for esophageal GIST because it facilitates safe and minimally invasive surgery in a limited space of the thoracic cavity.

•

There is no standard technique due to the anatomical peculiarities of the esophagus.

•

We think McKeown's procedure in the prone position has some advantages from others.

•

Robot surgery has a three-dimensional view, tremor control, and ambidexterity.

•

RAMIE would be useful techniques in a limited space of the thoracic cavity.

The Combined Usage of the Global Leadership Initiative on Malnutrition Criteria and Controlling Nutrition Status Score in Acute Care Hospitals

INTRODUCTION

The Global Leadership Initiative on Malnutrition (GLIM) lacks reliable blood tests for evaluating the nutrition status. We retrospectively compared the GLIM criteria, Controlling Nutrition Status (CONUT) score, and Subjective Global Assessment (SGA) to establish effective malnutrition screening and provide appropriate nutritional interventions according to severity.

METHODS

We classified 177 patients into 3 malnutrition categories (normal/mild, moderate, and severe) according to the GLIM criteria, CONUT score, and SGA. We investigated the malnutrition prevalence, concordance of malnutrition severity, predictability of clinical outcome, concordance by etiology, and clinical outcome by inflammation.

RESULTS

The highest prevalence of malnutrition was found using the GLIM criteria (87.6%). Concordance of malnutrition severity was low between the GLIM criteria and CONUT score. Concordance by etiology was low in all groups but was the highest in the "acute disease" group. The area under the curve of clinical outcome and that of the "with inflammation group" were significantly higher when using the CONUT score versus using the other tools (0.679 and 0.683, respectively).

CONCLUSION

The GLIM criteria have high sensitivity, while the CONUT score can effectively predict the clinical outcome of malnutrition. Their combined use can efficiently screen for malnutrition and patient severity in acute care hospitals.

Cadaver surgical training in Japan: its past, present, and ideal future perspectives

The framework for cadaver surgical training (CST) in Japan was established in 2012, based on the “Guidelines for Cadaver Dissection in Education and Research of Clinical Medicine” of the Japan Surgical Society (JSS) and the Japanese Association of Anatomists. Subsequently, the Ministry of Health, Labor and Welfare allocated funding from its budget for CST. By 2019, CST was being practiced in 33 medical schools and universities. Currently, the CST Promotion Committee of the JSS reviews each CST report submitted by medical schools and universities and provides guidance based on professional autonomy. This paper outlines the history of CST in Japan and presents a plan for its future. To sustain and oversee CST implementation, an operating organization, funded by stakeholders, such as government agencies, academic societies, and private companies, is needed.

Predicting the Outcomes of Postoperative Pancreatic Fistula After Pancreatoduodenectomy Using Prophylactic Drain Contrast Imaging

BACKGROUND

Postoperative pancreatic fistula is a main cause of fatal complications post-pancreatoduodenectomy. However, no universally accepted drainage management exists for clinically relevant postoperative pancreatic fistulas. We retrospectively evaluated cases in which drain contrast imaging was used to determine its utility in identifying clinically relevant postoperative pancreatic fistulas post-pancreatoduodenectomy.

METHODS

Between January 2014 and December 2018, 209 consecutive patients who underwent pancreatoduodenectomy in our institute were retrospectively analyzed. Drain monitoring with contrast imaging was performed in 47 of the cases. We classified drain contrast type into three categories and evaluated postoperative outcome in each group: (1) fistulous tract group-only the fistula was contrasted; (2) fluid collection group - fluid collection connected to the drain fistula; and (3) pancreatico-anastomotic fistula group-fistula connected to the digestive tract.

RESULTS

The durations of postoperative hospital stay and drainage were significantly shorter in the fistulous tract group than in the fluid collection group (31 vs. 46 days, p = 0.0026; and 12 vs. 38 days, p < 0.0001, respectively). The cost and number of drain exchanges were significantly lower in the fistulous tract group than in the fluid collection group ($163.6 vs. 467.5, p < 0.0001; and 1 vs. 5.5, p < 0.0001, respectively). Notably, no patient had grade C postoperative pancreatic fistula.

CONCLUSION

Classification of prophylactic drain contrast type can aid in predicting outcomes of clinically relevant postoperative pancreatic fistulas and optimizing drainage management.

Initial Results of Laparoscopic Proximal Gastrectomy With Double-tract Reconstruction Using Oblique Jejunogastrostomy Method on the Long-term Outcome of Postoperative Nutritional Status: A Propensity Score-matched Study

BACKGROUND

The aim of this study was to evaluate the long-term nutritional state of patients with gastric cancer who underwent laparoscopic proximal gastrectomy with double-tract reconstruction (LPG-DTR) using oblique jejunogastrostomy method (OJG).

METHODS

Medical records of 38 patients who underwent LPG-DTR using OJG (21 patients) or laparoscopic total gastrectomy with Roux-en-Y reconstruction (LTG-RY) (17 patients) between October 2011 and March 2018 were retrospectively reviewed. In these patients, clinicopathologic variables were analyzed using propensity score matching for age, sex, body mass index, American Society of Anesthesiologists physical state, clinical stage, and lymph node dissection. Operative outcomes and postoperative nutritional status were compared between the 2 groups.

RESULTS

A total of 16 patients were matched to analyze the LPG-DTR and LTG-RY groups. The serum hemoglobin, total protein, and albumin levels at 12 months postoperatively (P=0.008, 0.034, and 0.049) and serum hemoglobin level at 24 months (P=0.025) in the LPG-DTR group was significantly superior to those in the LTG-RY group.

CONCLUSIONS

The postoperative nutritional status as long-term outcomes of patients who underwent LPG-DTR using OJG was significantly superior to those who underwent LTG-RY. The results hereby presented suggest that LPG-DTR using OJG for gastric cancer produces better postoperative nutritional status.

Robotic Distal Gastrectomy With a Novel "Preemptive Retropancreatic Approach" During Dissection of Suprapancreatic Lymph Nodes for Gastric Cancer

INTRODUCTION

Abrogating contact with the pancreas in suprapancreatic lymph nodes dissection for gastric cancer can prevent pancreatic fistula because of postoperative pancreatic damage. Our novel "Preemptive retropancreatic approach" is a useful technique that minimizes pancreatic compression during robotic distal gastrectomy (RDG) with multijointed forceps. Here, we report the usefulness of RDG for gastric cancer surgery using our novel "Preemptive retropancreatic approach".

MATERIALS

"Preemptive retropancreatic approach": initial dissection of the bilateral retropancreatic space, the adherence between the retroperitoneum surface and the pancreas (fusion fascia) is released, providing a good operative field and hindering contact with the pancreas in suprapancreatic lymph nodes dissection during RDG. We herein reported consecutive 30 patients with gastric cancer who underwent RDG at Hokkaido University from September 2014 to March 2020.

RESULTS

All operations were performed by a single surgeon (Y.E.). The median operating time was 281 minutes (132 to 415). The median intraoperative bleeding was 0 ml of blood (0 to 255). There were 2 incidences of postoperative complications (≥Clavien-Dindo classification II), and there were no cases of postoperative pancreas-related complications. The median length of hospital stay after the surgery was 10 days (6 to 33).

CONCLUSION

As RDG for gastric cancer is still in its early introductory phase, its superiority has yet to be definitively established. However, we believe that "Preemptive retropancreatic approach" may reduce postoperative pancreatic-related complications in suprapancreatic lymph nodes dissection.

Sarcopenia in a patient with most serious complications after highly invasive surgeries treated with nutrition, rehabilitation, and pharmacotherapy: a case report

BACKGROUND

Several studies have reported the implementation of nutrition therapy and rehabilitation for acute and critical illnesses. However, rehabilitation nutrition for elderly sarcopenia patients with extremely severe postoperative complications during hospitalization has not yet been established.

CASE PRESENTATION

We report the case of a 70-year-old man with sarcopenia that developed as a postoperative complication of the surgical resection of perihilar cholangiocarcinoma and left the patient bedridden from prolonged malnutrition and muscle weakness. The patient's general condition improved after a nearly 6-month intervention by our Nutrition Support Team (NST) that combined nutrition, exercise, and pharmacotherapy.

CONCLUSIONS

The appropriate timing and order of pharmacotherapy, nutrient administration, exercise therapy, and team collaboration may enable elderly patients with severe (secondary) sarcopenia and postoperative complications to regain self-sustained walking.

Clinical Impact of Organ-Preserving Surgery for Pancreatic Neuroendocrine Neoplasms: A Single-Center Experience

OBJECTIVES

Organ-preserving surgery (OPS) has been accepted for pancreatic neuroendocrine neoplasms, particularly for the management of small tumors. This study aimed to analyze the surgical outcome following this treatment at our institute, focusing on the perioperative factors and postoperative locoregional recurrence.

METHODS

We analyzed 71 consecutive patients with no synchronous liver metastasis. These patients were classified into 1 of 2 groups: the standard operation group (SOG, 41 patients) with prophylactic regional lymph node dissection and the organ-preserving surgery group (OPG, 30 patients). We performed OPS based on size criteria (tumor size <1.5 cm in nonfunctional pancreatic neuroendocrine neoplasms and <2 cm in insulinoma with no evident bulky lymph node swelling on preoperative imaging).

RESULTS

The median follow-up periods were 37 months. The OPG included enucleation, partial resection, proximal parenchymal pancreatectomy, central pancreatectomy, spleen-preserving distal pancreatectomy, and Warshaw operation. The SOG included pancreatoduodenectomy and distal pancreatectomy, showing no statistically significant differences between the 2 groups in terms of operation time, hospitalization duration, and postoperative complications. Ten patients showed lymph node metastasis (25%) only in the SOG. There were no locoregional recurrent cases in the OPG.

CONCLUSIONS

In selected patients, OPS may be effective based on the appropriate tumor size criteria.

Laparoscopic real-time vessel navigation using indocyanine green fluorescence during the laparoscopic-Warshaw technique: First clinical experience

Background:

Laparoscopic-Warshaw technique (lap-WT) may be selected as a function-preserving operation for malignant border lesions in the tail region of the pancreas. However, previous reports showed that there are complications such as infection and abscess formation due to lack of blood flow to the spleen after surgery. To overcome the problems, we have performed real-time vessel navigation by using indocyanine green (ICG) fluorescence during lap-WT.

Materials and Methods:

We report our experience of three patients with pancreatic tumour who underwent real-time vessel navigation during lap-WT at Hokkaido University from May 2017 to September 2018.

Results:

The median operating time was 339 min (174–420). The median intraoperative bleeding was 150 ml (0–480). There were no incidences of complications. There were no cases with post-operative spleen ischaemia or abscess formation and varices formation.

Conclusion:

We believe that laparoscopic real-time vessel navigation using indocyanine green fluorescence during lap-WT could contribute in reducing the post-operative spleen-related complications.

A novel laparoscopic near-infrared fluorescence spectrum system for photodynamic diagnosis of peritoneal dissemination in pancreatic cancer

BACKGROUND

Diagnosing peritoneal dissemination is essential for selecting the appropriate therapeutic strategy for patients with pancreatic cancer. Intraoperative laparoscopic diagnosis enables the selection of less invasive surgical strategies. Photodynamic diagnosis using 5-aminolevulinic acid may improve gastrointestinal cancer diagnostic accuracy, although weak fluorescence is not easily detected. Here we aimed to improve this sensitivity using laparoscopic spectrophotometry.

METHODS

Photodynamic diagnosis was performed using serial dilutions of protoporphyrin IX, and its detectability using laparoscopic spectrophotometry was compared with that using naked-eye observation. Five-aminolevulinic acid-photodynamic diagnosis was performed for pancreatic cancer cell lines, and a murine peritoneal disseminated nodule model was established. We compared laparoscopic spectrophotometry and naked-eye observation results using white and fluorescent lights and compared them to routine histopathological examination results. Photodynamic diagnoses were made in 2017 and 2018 in eight patients with pancreatic cancer.

RESULTS

Weaker fluorescence of the diluted protoporphyrin IX samples was better detected with spectrophotometry than with naked-eye observation. Moreover, a spectrograph of protoporphyrin IX in multiple cell lines was detected by spectrophotometry. In the murine model, the detection rates were 62 %, 78 %, and 90 % for naked-eye observation with white light, fluorescent light, and spectrophotometry, respectively. Comparisons of fluorescent light-negative peritonea with and without pathological metastases showed significantly higher spectrophotometric intensities in the former (P < 0.010). In clinical studies, three fluorescent light-negative spectrophotometry-positive pathologically metastatic lesions were observed.

CONCLUSIONS

Laparoscopic spectrophotometry in the murine model and extraperitoneally photodynamic diagnoses using spectrophotometry in clinical practice are sensitive photodynamic diagnostic techniques.

Pancreatic body and tail cancer and favorable metastatic lymph node behavior on the left edge of the aorta

BACKGROUND

Lymph node (LN) metastasis in pancreatic body-tail cancer is a poor prognostic factor and the optimal LN dissection area for distal pancreatectomy (DP) remains unclear. Lymphatic flow from the tumors is thought to depend on the tumor sites. We examined LN metastasis frequency based on tumor site and recurrent patterns post-DP.

METHODS

With a retrospective, single institutional study, we examined 100 patients who underwent DP as an upfront surgery for pancreatic cancer over 17 years. Tumor sites were classified as tumor confined to pancreatic body (and neck) (Pb(n)); and pancreatic tail (Pt). We compared metastatic LN and recurrence patterns based on tumor site. The median overall survival (OS) and disease-free survival (DFS) were analyzed.

RESULTS

LN metastasis occurred in 59/100 (59.0%), with 23 and 25 tumors located in the Pb(n), and Pt, respectively. Those with the tumor in Pt had metastases to #10, #11d/p, and #18 LN mainly. However, the patients with the Pb(n) tumor had metastases to #8a/p, #11p, and #14p/d LN. There was no metastasis to #10 and #11d LN. The OS and DFS were 34 and 15 months, respectively. No significant difference was found in the OS, DFS, and recurrence patterns based on tumor sites.

CONCLUSION

Differences in metastatic LN sites were observed in pancreatic body-tail cancer when tumors were confined to the left or right of the left aortic edge. Although it is necessary to validate this finding with a large-scale study, organ-preserving DP might be a treatment option for selected patients depending on the tumor sites.

Outcomes of limited resection for patients with intraductal papillary mucinous neoplasm of the pancreas: A single-center experience

BACKGROUND

/ObjectivesThe aim of this study was to clarify the oncological outcomes of patients with intraductal papillary mucinous neoplasm (IPMN) who underwent limited resection (LR).

METHODS

This retrospective study analyzed the data of 110 patients with IPMN. Patients with IPMN without a history of pancreatitis who had neither tumor infiltration nor regional lymph node swelling on imaging findings underwent LR. We assessed the oncological outcomes of LR for patients with IPMN by comparing the surgical outcomes of LR and standard resection.

RESULTS

LR was performed in 50 patients (45.5%), including duodenum-preserving pancreatic head resection (n = 31), middle-pancreatectomy (n = 12), spleen-preserving distal pancreatectomy (n = 3), total parenchymal pancreatectomy (n = 3), and partial resection (n = 1). In the LR group, 18 patients had postoperative complications of Clavien-Dindo classification ≥ IIIa. After histopathological examination, the presence of high-grade dysplasia (HGD) and invasive carcinoma (IC) were observed in nine and three patients, respectively, in the LR group, and eight and 22 patients, respectively, in the standard resection group. There was a significant difference in the histopathological diagnosis of IC between the two groups (p < 0.001). Finally, in the LR group, postoperative recurrences occurred in three patients, and the 5-, 10-, and 15-year disease-specific survival rates were all 97.0%.

CONCLUSIONS

For patients with IPMN judged to have no infiltrating lesions based on the detailed imaging examination, LR is acceptable and may be considered as an alternative to standard resection.

Laparoscopic-assisted distal gastrectomy and central pancreatectomy for gastric and perigastric lymph node metastases and pancreatic invasion from melanoma: a case report

Background

In melanoma, completely resectable metastases are surgically resected to expect to prolong relapse-free survival and overall survival. However, distant metastases of melanoma are rarely indicated for surgery because multiple metastases are often observed at diagnosis. We report a case of a man in his 50s who underwent laparoscopic-assisted distal gastrectomy and central pancreatectomy for gastric metastases, lymph node metastases, and pancreatic invasion that could be completely resected.

Case presentation

A 50-year-old man was diagnosed with malignant melanoma of the left parietal region. After diagnosis, tumor resection and left cervical lymph node dissection were performed, and interferon-β treatment was added as adjuvant therapy. Seventeen months after adjuvant therapy, metastasis of stomach and abdominal lymph nodes from melanoma was diagnosed. And the pancreatic invasion of lymph nodes was suspected. Laparoscopic-assisted distal gastrectomy and the central pancreatectomy were performed because pancreatic invasion of melanoma was intraoperatively found. After 9 months of relapse-free survival, abdominal recurrence was observed. Nivolumab and ipilimumab were administered, and recurrent lesions are currently controlled. The patient has survived more than 3 years since metastasis resection.

Conclusion

In conclusion, laparoscopic-assisted distal gastrectomy and the central pancreatectomy were performed for gastric and perigastric lymph node metastases and pancreatic invasion due to malignant melanoma, and the negative surgical margin was achieved. Although patient selection is required, the central pancreatectomy was a good indication for maintaining exocrine and endocrine function. The development of immune checkpoint inhibitors and molecular-targeted agents may increase gastrointestinal surgery for metastatic melanoma in the future.

The effect of the body mass index on the short-term surgical outcomes of laparoscopic total gastrectomy: A propensity score-matched study

Purpose

This study aimed to evaluate the relationship between the body mass index (BMI) and the short-term outcomes of laparoscopic total gastrectomy (LTG).

Subjects and Methods

Data of patients who underwent LTG for gastric cancer at six institutions between 2004 and 2018 were retrospectively collected. The patients were classified into three groups: low BMI (<18.5 kg/m²), normal BMI (≥18.5 and <25 kg/m²) and high BMI (≥25 kg/m²). In these patients, clinicopathological variables were analysed using propensity score matching for age, sex, the American Society of Anaesthesiologists physical state, clinical stage, surgical method, D2 lymph node dissection, combined resection of other organs, anastomosis method and jejunal pouch reconstruction. The surgical results and post-operative outcomes were compared among the three groups.

Results

A total of 82 patients were matched in the analysis of the low BMI and normal BMI groups. There were no differences in operative time (P = 0.693), blood loss (P = 0.150), post-operative complication (P = 0.762) and post-operative hospital stay (P = 0.448). In the analysis of the normal BMI and high BMI groups, 208 patients were matched. There were also no differences in blood loss (P = 0.377), post-operative complication (P = 0.249) and post-operative hospital stay (P = 0.676). However, the operative time was significantly longer in the high BMI group (P = 0.023).

Conclusions

Despite the association with a longer operative time in the high BMI group, BMI had no significant effect on the surgical outcomes of LTG. LTG could be performed safely regardless of BMI.

Robot-assisted laparoscopic total gastrectomy for Epstein-Barr virus-associated multiple gastric cancer: A case report

•

It is unclear how Epstein–Barr virus causes cancer.

•

EBVaGC should be considered when multiple gastric cancer is recognized.

•

Robotic surgery has high-resolution three-dimensional images.

•

Using forceps with multi-joint functions was effective for this case.

Introduction

Epstein–Barr virus-associated gastric cancer (EBVaGC) sometimes appears as multiple gastric cancer lesions. Here, we report a case of robot-assisted laparoscopic total gastrectomy (RTG) for a relatively rare disease with four synchronized lesions in EBVaGC and discuss the usefulness of robotic gastrectomy.

Presentation of case

A 60-year-old woman was diagnosed with multiple gastric cancer because she had five lesions in the stomach and biopsy showed the presence of adenocarcinoma in four of the five lesions. We performed robot-assisted laparoscopic total gastrectomy on the patient. The histopathological diagnosis was multiple gastric cancer T1bN0M0 pStage IA. The four lesions were positive for the Epstein–Barr virus encoding region in in-situ hybridization and were considered to be EBVaGC. The patient had no sign of recurrence without postoperative therapy for 24 months.

Disscussion

EBVaGC was found in about 10% of all gastric cancer cases worldwide. EBVaGC sometimes appears as multiple gastric cancer, suggesting that EBV infection is closely related to the early stages of tumor formation. Total gastrectomy may be necessary for multiple gastric cancer such as EBVaGC, and robotic surgery is useful in total gastrectomy in terms of high-resolution three-dimensional images and using forceps with multi-joint functions.

Conclusions

We performed RTG on a patient with four synchronous lesions of EBVaGC, which is relatively rare. Robot-assisted laparoscopic total gastrectomy is known to be a safe procedure, and we effectively performed total gastrectomy for multiple EBVaGC.

Two emergency cases of spontaneous esophageal perforation treated using a minimally invasive abdominal and left thoracic approach

Boerhaave's syndrome is a rare life-threatening disease that requires prompt intervention. Thoracotomy has traditionally been considered the gold standard approach for treatment, but other minimally invasive approaches have recently been reported. Our institute reported the efficacy of minimally invasive abdominal and left thoracic approach in the treatment of patients with esophagogastric junction cancer and introduced it for the treatment of two patients with Boerhaave's syndrome. We intraoperatively sutured the rupture sites and irrigated the pleural cavity using thoracoscopy. Then, after confirming the absence of intraabdominal contamination, we performed jejunostomy or gastrostomy using laparoscopy. Patients' vital signs remained stable intraoperatively, and their postoperative periods were uneventful with no leakage or stricture. The minimally invasive abdominal and left thoracic approach for Boerhaave's syndrome is convenient and useful as it provides excellent visualization of the thoracic and abdominal cavities with the possibility of quickly switching between views.

Time to Recurrence After Surgical Resection and Survival After Recurrence Among Patients with Perihilar and Distal Cholangiocarcinomas

BACKGROUND

The differences between perihilar cholangiocarcinoma (PHCC) and distal cholangiocarcinoma (DCC) regarding recurrence and the factors that affect recurrence after surgery are unclear. This study aims to investigate the differences in recurrence patterns between patients with PHCC and those with DCC after surgical resection with curative intent. It also investigates the risk factors associated with recurrence and survival thereafter.

PATIENTS AND METHODS

The postoperative courses of 366 patients with extrahepatic cholangiocarcinomas (EHCCs), including 236 with PHCC and 130 with DCC, who underwent surgical resections were investigated retrospectively.

RESULTS

During follow-up, tumors recurred in 143 (60.6%) patients with PHCC and in 72 (55.4%) patients with DCC. Overall survival (OS) after surgery, recurrence-free survival (RFS), and OS after recurrence were similar for the patients with PHCC and those with DCC. The cumulative probability of recurrence declined 3 years after surgery in the patients with PHCC and those with DCC. A multivariable analysis determined that, among the patients with PHCC and those with DCC, regional lymph node metastasis was a significant risk factor associated with RFS. Ten patients with PHCC and eight patients with DCC with two or fewer sites of recurrence in a single organ underwent resections. A multivariable analysis determined that recurrent tumor resection was an independent prognostic factor associated with OS after recurrence in the patients with PHCC and those with DCC.

CONCLUSIONS

Postoperative survival did not differ between the patients with PHCC and those with DCC. Frequent surveillances for recurrence are needed for 3 years after surgical resection of EHCCs. In selected patients, surgery for recurrent EHCCs might be associated with improved outcomes.

A minimally invasive abdominal and left thoracic approach as a palliative treatment for adenocarcinoma of the esophagogastric junction with severe stenosis: A case report

We report a novel technique for combined laparoscopy and thoracoscopy for far-advanced adenocarcinoma of the esophagogastric junction (AEG). A 56-year-old man presented with far-advanced AEG, and an esophagogastroduodenoscopy revealed a type 2 lesion that encircled the esophagogastric junction. CT revealed stenosis of the esophagogastric junction, suspected invasion into the left side of the diaphragm, and lymph node metastases in the abdomen. We diagnosed Siewert type II AEG (cT4aN1M0, cStage IIIA) according to the Japanese Classification of Gastric Carcinoma, version 14. Laparoscopic and thoracoscopic proximal gastrectomy and lower esophagectomy with double-tract reconstruction were performed as a palliative resection via a minimally invasive abdominal and left thoracic approach. However, localized peritoneal dissemination was detected. The patient was discharged with no postoperative morbidity. Hence, a minimally invasive abdominal and left thoracic approach provides good visualization, and it is safe for lower esophageal transection and intrathoracic anastomosis in the treatment of locally advanced AEG invading the surrounding tissues.

An Unmodulated Very-Low-Voltage Electrosurgical Technology Creates Predictable and Ultimate Tissue Coagulation: From Experimental Data to Clinical Use

Objective. We analyzed the underlying principles of an unmodulated very-low-voltage (VLV) mode, designated as “soft coagulation” in hemostasis, and demonstrate its clinical applications. Summary Background Data. While the advantage of the VLV mode has been reported across surgical specialties, the basic principle has not been well described and remains ambiguous. Methods. Characteristics of major electrosurgical modes were measured in different settings. For the VLV mode, the tissue effect and electrical parameters were assessed in simulated environments. Results. The VLV mode achieved tissue coagulation with the lowest voltage compared with the other modes in any settings. With increasing impedance, the voltage of the VLV mode stayed very low at under 200 V compared with other modes. The VLV mode constantly produced effective tissue coagulation without carbonization. We have demonstrated the clinical applications of the method. Conclusions. The voltage of the VLV mode consistently stays under 200 V, resulting in tissue coagulation with minimal vaporization or carbonization. Therefore, the VLV mode produces more predictable tissue coagulation and minimizes undesirable collateral thermal tissue effects, enabling nerve- and function-preserving surgery. The use of VLV mode through better understanding of minimally invasive way of using electrosurgery may lead to better surgical outcomes.

Metachronous liver metastases after long-term follow-up of endoscopic resection for rectal neuroendocrine neoplasms: a report of three cases

Background

Rectal neuroendocrine neoplasms (NENs) are rare, but their incidence has increased in recent years. The metastasis rate is low in cases of a tumor diameter < 1 cm or depth of invasion lower than the submucosa; therefore, the European Neuroendocrine Tumor Society (ENETS) and the North American Neuroendocrine Tumor Society (NANETS) consensus guidelines recommend endoscopic resection. Since little has been reported on the long-term prognosis of endoscopic resection for rectal NEN, consensus is lacking regarding the follow-up period after endoscopic resection.

Case presentation

Here, we report three cases of metachronous liver metastasis after long-term follow-up of endoscopic mucosal resection (EMR) for rectal NEN. The pathological findings indicated a depth lower than the submucosa and complete radical resection in all cases and lymphovascular invasion in only one case. All three cases showed metachronous multiple liver metastases after 9–13 years of follow-up for EMR, despite achieving complete resection and without muscular invasion.

Conclusions

Metachronous liver metastases may occur after long interval following endoscopic resection; thus, long-term follow-up is necessary after endoscopic resection for rectal NEN.

Role of Dimerized C16orf74 in Aggressive Pancreatic Cancer: A Novel Therapeutic Target

Over the past 30 years, the therapeutic outcome for pancreatic ductal adenocarcinoma (PDAC) has remained stagnant due to the lack of effective treatments. We performed a genome-wide analysis to identify novel therapeutic targets for PDAC. Our analysis showed that Homo sapiens chromosome 16 open reading frame 74 (C16orf74) was upregulated in most patients with PDAC and associated with poor prognosis. Previously, we demonstrated that C16orf74 interacts with the catalytic subunit alpha of protein phosphatase 3 and plays an important role in PDAC invasion. However, the pathophysiologic function of C16orf74 is still unclear. In this study, through the analysis of C16orf74 interaction, we demonstrate a new strategy to inhibit the growth and invasion of PDAC. C16orf74 exists in the homodimer form under the cell membrane and binds integrin αVβ3 and is also involved in invasion by activating Rho family (Rac1) and MMP2. Considering that this dimeric form was found to be involved in the function of C16orf74, we designed an 11R-DB (dimer block) cell-permeable dominant-negative peptide that inhibits the dimer form of C16orf74. 11R-DB suppressed invasion and proliferation of PDAC cell lines by inhibiting phosphorylation of Akt and mTOR and also by inactivation of MMP2. 11R-DB also showed antitumor effects in an orthotopic xenograft model and peritoneal metastasis model. Thus, this study demonstrates that dimerized C16orf74, present in the cell membrane, is involved in pancreatic cancer invasion and proliferation. In addition, the C16orf74 dimer block cell-permeable peptide (11R-DB) has a potent therapeutic effect on PDAC in vitro and in vivo.

Jejunal intussusception at the jejunojejunostomy after laparoscopic total gastrectomy: A case report

Jejunal intussusception at the jejunojeunostomy after total gastrectomy with Roux-en-Y (RY) reconstruction is rare. We describe a case of jejunal intussusception at the jejunojeunostomy that developed in a 60-year-old woman who had undergone laparoscopic total gastrectomy with RY reconstruction for gastric cancer 4 years ago. The main presenting complaint was recurrent epigastric pain. Abdominal computed tomography showed a typical target sign suspected of antegrade intussusception into a blind loop at the jejunojeunostomy. We performed a laparoscopic operation, which revealed no intussusception or adhesions. We noted that the blind loop of the bilio-pancreatic limb was longer and expanded. We divided the blind loop at the distal side of the jejunojeunostomy and performed suture plication between the bilio-pancreatic limb and alimentary limb. Therefore, the appropriate length of the blind loop and the size of the jejunojeunostomy site should be carefully determined during RY reconstruction.

Evaluation methods and impact of simulation-based training in pediatric surgery: a systematic review

PURPOSE

The aim of this study was to identify (1) the type of skill evaluation methods and (2) how the effect of training was evaluated in simulation-based training (SBT) in pediatric surgery.

METHODS

Databases of PubMed, Cochrane Library, and Web of Science were searched for articles published from January 2000 to January 2017. Search concepts of Medical Subject Heading terms were "surgery," "pediatrics," "simulation," and "training, evaluation."

RESULTS

Of 5858 publications identified, 43 were included. Twenty papers described simulators as assessment tools used to evaluate technical skills. Reviewers differentiated between experts and trainees using a scoring system (45%) and/or a checklist (25%). Simulators as training tools were described in 23 papers. While the training's effectiveness was measured using performance assessment scales (52%) and/or surveys (43%), no study investigated the improvement of the clinical outcomes after SBT.

CONCLUSION

Scoring, time, and motion analysis methods were used for the evaluation of basic techniques of laparoscopic skills. Only a few SBT in pediatric surgery have definite goals with clinical effect. Future research needs to demonstrate the educational effect of simulators as assessment or training tools on SBT in pediatric surgery.

Identifying the Essential Portions of the Skill Acquisition Process Using Item Response Theory

OBJECTIVE

Item response theory (IRT) was originally developed to make performance assessments more accurate. However, IRT analysis of the intraoperative performance of surgical trainees could help identify the elements that the trainees find difficult during the skill acquisition process. The aim of this study was to identify the essential portions of the skill acquisition process of a surgical procedure using the IRT.

DESIGN

The 24-item assessment checklist was used to evaluate a recorded intra-operative performance of a laparoscopic inguinal hernia repair. The scores were analyzed using IRT to calculate the difficulty and discrimination level of each item.

SETTING

Fifteen institutes.

PARTICIPANTS

Thirty surgical trainees.

RESULTS

A total of 123 assessments were analyzed. The item analysis showed the procedure specific item "traction of peritoneum (difficulty: -0.45; discrimination: 19.37)" and generic items "instrument handling (difficulty: -0.59; discrimination: 3.82)" and "flow of procedure (difficulty: 0.09; discrimination: 3.27)" to be key elements in the skill acquisition process of the procedure.

CONCLUSIONS

Key elements in the skill acquisition process of the procedure were quantitatively identified by applying the IRT analysis. This could lead to the use of IRT in designing and developing a more effective training curriculum.