Surgical Outcomes of Pancreatectomy with Resection of the Portal Vein and/or Superior Mesenteric Vein and Jejunal Vein for Pancreatic Head Cancer: A Multicenter Study

OBJECTIVE

The aim of this study was to investigate the safety and survival benefits of portal vein and/or superior mesenteric vein (PV/SMV) resection with jejunal vein resection (JVR) for pancreatic ductal adenocarcinoma (PDAC).

SUMMARY BACKGROUND DATA

Few studies have shown the surgical outcome and survival of pancreatic resection with JVR, and treatment strategies for patients with PDAC suspected of jejunal vein (JV) infiltration remain unclear.

METHODS

In total, 1260 patients who underwent pancreatectomy with PV/ SMV resection between 2013 and 2016 at 50 facilities were included; treatment outcomes were compared between the PV/SMV group (PV/ SMV resection without JVR; n = 824), PV/SMV-J1 V group (PV/SMV resection with first jejunal vein resection; n = 394), and PV/SMV-J2,3 V group (PV/SMV resection with second jejunal vein or later branch resection; n = 42).

RESULTS

Postoperative complications and mortality did not differ between the three groups. The postoperative complication rate associated with PV/ SMV reconstruction was 11.9% in PV/SMV group, 8.6% in PV/SMV-J1 V group, and 7.1% in PV/SMV-J2,3V group; there were no significant differences among the three groups. Overall survival did not differ between PV/SMV and PV/SMV-J1 V groups (median survival; 29.2 vs 30.9 months, P = 0.60). Although PV/SMV-J2,3 V group had significantly shorter survival than PV/SMV group who underwent upfront surgery ( P = 0.05), no significant differences in overall survival of patients who received preoperative therapy. Multivariate survival analysis revealed that adjuvant therapy and R0 resection were independent prognostic factors in all groups.

CONCLUSION

PV/SMV resection with JVR can be safely performed and may provide satisfactory overall survival with the pre-and postoperative adjuvant therapy.

A case of premortem diagnosis of cardiac tamponade due to pericardial metastasis of rectal cancer

Colorectal cancer rarely develops pericardial metastasis, and it is an extremely rare case that cardiac tamponade due to the metastasis of colorectal cancer during life. Our case is of a 50-year-old woman who underwent laparoscopic lower anterior resection for the rectal cancer with lung metastasis 4 years ago developed cardiac tamponade due to pericardial metastasis of rectal cancer. We performed pericardiocentesis as a temporary life-saving procedure, but pericardial fluid re-accumulated within a few days. She died 23 days after admission. When a patient with advanced colorectal cancer complains dyspnea, we should consider the pericardial metastasis, and perform the proper treatment as this case.

[Preoperative Prognostic Factors in CRS plus HIPEC for Patients with Peritoneal Dissemination of Colorectal Cancer]

Peritoneal dissemination of colorectal cancer has the poorest prognosis among metastatic sites, with an average overall survival of less than 6 months. Various treatment methods have been reported for these patients, and recently there have been several reports showing the usefulness of cytoreductive surgery(CRS)combined with hyperthermic intraperitoneal chemotherapy (HIPEC). However, the studies on this treatment are limited. In this study, we retrospectively reviewed cases of CRS plus HIPEC. Twenty-one patients who underwent CRS plus HIPEC at Tokyo Medical University Hospital and Toda Central General Hospital between August 2014 and December 2017 were included in this study. The long-term and short-term survival groups were analyzed separately, and predictors of preoperative treatment efficacy were examined. The surgical approach was open in 16 cases and laparoscopic in 5 cases. Complete resection was achieved in 10 of these patients. Postoperative complications occurred in 6 patients. There were no deaths within 90 days of surgery. The median overall survival was 17.0 months, and the 1-year survival rate was 65%. Median progression-free survival was 11.0 months. In a multivariate analysis predicting long-term versus short-term survival groups, sex, primary tumor location, and P factor were independent predictors of treatment response. CRS plus HIPEC therapy is considered an effective treatment option. The predictors of preoperative treatment response include sex, primary tumor location, and P factor.

Retroperitoneal hibernoma resected via laparoscopic surgery

Hibernomas are extremely rare, benign tumors of brown fat origin with no specific symptoms. Surgery is the only treatment option, and because a definitive preoperative diagnosis is often not obtained, open surgery is usually chosen. In this case, we performed laparoscopic surgery on a 33-year-old woman with retroperitoneal hibernoma. As in most cases, a definitive diagnosis had not been preoperatively made; therefore, we laparoscopically removed the retroperitoneal tumor of unknown pathology as a diagnostic treatment. We chose laparoscopic surgery because of the magnifying effect of the laparoscope and to minimize scarring. The surgery was uneventful, with a procedure time of 280 minutes and a blood loss of 20 mL. The postoperative course was uneventful with no complications or recurrence. We conclude that laparoscopic surgery may be a viable option for hibernomas.

[Multiple Intestinal Perforations Caused by Diffuse Large B-Cell Lymphoma-A Case Report]

A 83-year-old man was diagnosed with diffuse large B-cell lymphoma and scheduled for treatment. However, he developed abdominal pain, and computed tomography revealed a gastrointestinal perforation. Emergency surgery was performed, upon which we identified perforations in the small intestine, and we therefore performed resection of the small intestine. R-CHOP therapy was performed postoperatively, resulting in successful tumor shrinkage. Malignant lymphoma of the small intestine often causes intestinal perforations, and the prognosis of patients with perforations is unfavorable. We report a case of a patient with multiple intestinal perforations owing to malignant lymphoma of the small intestine, in whom minimal surgery was performed and intervention in the early postoperative period was successful.

Artificial intelligence predicts lymph node metastasis or risk of lymph node metastasis in T1 colorectal cancer

BACKGROUND

The treatment strategies for colorectal cancer (CRC) must ensure a radical cure of cancer and prevent over/under treatment. Biopsy specimens used for the definitive diagnosis of T1 CRC were analyzed using artificial intelligence (AI) to construct a risk index for lymph node metastasis.

METHODS

A total of 146 T1 CRC cases were analyzed. The specimens for analysis were mainly biopsy specimens, and in the absence of biopsy specimens, the mucosal layer of the surgical specimens was analyzed. The pathology slides for each case were digitally imaged, and the morphological features of cancer cell nuclei were extracted from the tissue images. First, statistical methods were used to analyze how well these features could predict lymph node metastasis risk. A lymph node metastasis risk model using AI was created based on these morphological features, and accuracy in test cases was verified.

RESULTS

Each developed model could predict lymph node metastasis risk with a > 90% accuracy in each region of interest of the training cases. Lymph node metastasis risk was predicted with 81.8-86.3% accuracy for randomly validated cases, using a learning model with biopsy data. Moreover, no case with lymph node metastasis or lymph node risk was judged to have no risk using the same model.

CONCLUSIONS

AI models suggest an association between biopsy specimens and lymph node metastases in T1 CRC and may contribute to increased accuracy of preoperative diagnosis.

Comparison of pressure resistance of double-rows and triple-rows circular stapler in rectal double stapling technique: In vitro study

BACKGROUND

Anastomotic leak after gastrointestinal anastomosis is a serious complication. Anastomotic failure depends on various parameters. The aim of our study was to evaluate the pressure resistance of a new device, EEA™ circular stapler with Tri-Staple™ technology 28 mm Medium/Thick (Triple-rows circular stapler; TCS) compared with EEA™ circular stapler with DST series™ technology 28 mm, 4.8 mm staples (double-rows circular stapler; DCS).

PATIENTS AND METHODS

We performed 30 anastomoses (DSC: 15, TCS: 15) of DST with porcine colon model in vitro. We performed following 3 comparative experiences; Experiment 1: observation of staple shape with a colonoscopy, Experiment 2: comparison of the pressure resistance, Experiment 3: comparison of leakage points.

RESULTS

There was no hypoplasia of staples and the shapes were well-formed by colonoscopy. The leakage pressure of DCS was 19.6 ± 4.4 mm Hg (mean ± standard deviation) and that of TCS was 38.6 ± 10.2 mm Hg (mean ± standard deviation). There was a significantly difference between 2 groups (P < .001). 12 cases of DCS (80%) and 10 cases of TCS (66.7%) had leakages from Circular stapler point. 2 cases of DCS (13.3%) and 5 cases of TCS (33.3%) had leakages from Crossing points. Only 1 case of DCS had leakages from Dog ear point (6.7%). There was no significantly difference in leakage site between 2 groups (P = .195).

CONCLUSIONS

TSC showed high pressure resistance during DST compared with that of DCS. It was suggested that TCS may contribute to the reduction of anastomotic leakage rate.

Effectiveness of a new triple-row circular stapler in reducing the risk of colorectal anastomotic leakage: A historical control and propensity score-matched study

Anastomotic leakage (AL) after colorectal surgery is a serious complication. This study aimed to evaluate the effectiveness of the EEA™ circular stapler, a new triple-row circular stapler (TCS), relative to a conventional, double-row circular stapler (DCS). A total of 285 patients who underwent anastomosis with the double stapling technique at the Tokyo Medical University Hospital between 2017 and 2021 were included in this nonrandomized clinical trial with historical controls using a propensity score (PS) analysis. The primary endpoint was the risk of AL. We performed a 1:2 PS matching analysis. Before case matching, AL occurred in 15 (7.4%) and 2 (2.4%) patients in the DCS and TCS groups, respectively, with no significant difference (P = .17). After case matching, AL occurred in 13 patients (11.6%) and 1 patient (1.8%) in the DCS and TCS groups, respectively, revealing a significant difference (P = .04). Cox models were created by applying PS to adjust for group differences via regression adjustment. Odds ratios for AL in the DCS group versus the TCS group were 0.31 (95% confidence interval [CI]: 0.07-1.38) in the entire cohort, 0.15 (95% CI: 0.02-0.64) in the regression adjustment cohort, and 0.14 (95% CI: 0.02-1.09) in the 1:2 PS-matched cohort. PS analysis of clinical data suggested that the use of TCS contributes to a reduced risk of AL after colorectal anastomosis CTwith the double stapling technique.

New criteria of resectability for pancreatic cancer: A position paper by the Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHBPS)

The symposium "New criteria of resectability for pancreatic cancer" was held during the 33nd meeting of the Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHBPS) in 2021 to discuss the potential modifications that could be made in the current resectability classification. The meeting focused on setting the foundation for developing a new prognosis-based resectability classification that is based on the tumor biology and the response to neoadjuvant treatment (NAT). The symposium included selected experts from Western and Eastern high-volume centers who have discussed their concept of resectability status through published literature. During the symposium, presenters reported new resectability classifications from their respective institutions based on tumor biology, conditional status, pathology, and genetics, in addition to anatomical tumor involvement. Interestingly, experts from all the centers reached the agreement that anatomy alone is insufficient to define resectability in the current era of effective NAT. On behalf of the JSHBPS, we would like to summarize the content of the conference in this position paper. We also invite global experts as internal reviewers of this paper for intercontinental cooperation in creating an up-to-date, prognosis-based resectability classification that reflects the trends of contemporary clinical practice.

Salivary metabolomics with machine learning for colorectal cancer detection

As the worldwide prevalence of colorectal cancer (CRC) increases, it is vital to reduce its morbidity and mortality through early detection. Saliva‐based tests are an ideal noninvasive tool for CRC detection. Here, we explored and validated salivary biomarkers to distinguish patients with CRC from those with adenoma (AD) and healthy controls (HC). Saliva samples were collected from patients with CRC, AD, and HC. Untargeted salivary hydrophilic metabolite profiling was conducted using capillary electrophoresis–mass spectrometry and liquid chromatography–mass spectrometry. An alternative decision tree (ADTree)‐based machine learning (ML) method was used to assess the discrimination abilities of the quantified metabolites. A total of 2602 unstimulated saliva samples were collected from subjects with CRC (n = 235), AD (n = 50), and HC (n = 2317). Data were randomly divided into training (n = 1301) and validation datasets (n = 1301). The clustering analysis showed a clear consistency of aberrant metabolites between the two groups. The ADTree model was optimized through cross‐validation (CV) using the training dataset, and the developed model was validated using the validation dataset. The model discriminating CRC + AD from HC showed area under the receiver‐operating characteristic curves (AUC) of 0.860 (95% confidence interval [CI]: 0.828‐0.891) for CV and 0.870 (95% CI: 0.837‐0.903) for the validation dataset. The other model discriminating CRC from AD + HC showed an AUC of 0.879 (95% CI: 0.851‐0.907) and 0.870 (95% CI: 0.838‐0.902), respectively. Salivary metabolomics combined with ML demonstrated high accuracy and versatility in detecting CRC.

Comparison of Intracorporeal Trapezoidal-shaped Gastroduodenostomy and Delta-shaped Anastomosis After Laparoscopic Distal Gastrectomy for Gastric Cancer: A Single-center Retrospective Study

BACKGROUND

Laparoscopic/robotic distal gastrectomy (LDG/RDG) as a treatment for early gastric cancer has become increasingly and widely accepted for its minimal invasiveness and proportionate outcomes. Over the years, in addition to the LDG/RDG technique and the lymphadenectomy and gastrectomy procedures, various reconstruction methods have been developed and further improved upon. In particular, the number of minimally invasive intracorporeal anastomosis reconstruction techniques has been increasing.

MATERIALS AND METHODS

The medical records of 445 patients with gastric cancer who underwent reconstruction following LDG/RDG via either trapezoidal-shaped gastroduodenostomy (TAPESTRY; n=126) or delta-shaped anastomosis (DSA; n=319) at our hospital between April 2012 and May 2021 were retrospectively reviewed. Short-term surgical outcomes, including the operation time, blood loss, length of hospital stay, and complications, were compared between the 2 groups. Anastomosis-related complications, namely leakage, bleeding, stricture, and delayed gastric emptying, were monitored and graded using the Clavien-Dindo classification.

RESULTS

All operations were either performed or supervised by qualified surgeons. Patients' characteristics in the TAPESTRY group and the DSA group were biased in terms of the surgical approach, but they were well-balanced after propensity score matching. Overall anastomosis-related complications (Clavien-Dindo grade II or above) within 30 days after surgery in the TAPESTRY group were comparable with those in the DSA group, either all patients (1.5% vs. 5.0%, P=0.115) or after propensity score-matching analysis (2.1% vs. 6.5%, P=0.134). There were no records of reoperation or mortality during hospitalization in either group.

CONCLUSIONS

TAPESTRY was performed safely, with a low rate of anastomosis-related complications. These findings suggest that trapezoidal-shaped gastroduodenostomy could be a feasible option for reconstruction in patients undergoing LDG/RDG.

Efficacy and Safety of mFOLFOX6 as Perioperative Chemotherapy for Resectable Liver Metastases from Colorectal Cancer: A Case-Control Study

BACKGROUND/AIM

Although resection is effective for managing resectable liver metastases from colorectal cancer, the clinical significance of chemotherapy for such metastases has remained undetermined. Therefore, we conducted a phase II trial of perioperative chemotherapy with mFOLFOX6 to examine its efficacy.

PATIENTS AND METHODS

A total of 41 patients were examined. The liver resection rate was the primary endpoint, whereas the response rate, adverse events, completion rate, liver injury rate, R0 resection rate, and histological results were the secondary endpoints.

RESULTS

Overall, 34 (82.9%) patients underwent liver resection, and 77.4% and 100% had synchronous and metachronous liver metastases, respectively. The seven remaining patients did not undergo resection because of progressive disease. Moreover, 2, 15, 17, and 7 patients had a complete response, partial response, stable disease, and progressive disease, respectively, which indicated that the response rate was 41.5%. Regarding adverse events, three patients exhibited Grade 3 myelosuppression and one patient had gastrointestinal symptoms. On the basis of histopathological examination, 27, 5, and 2 patients belonged to grades 1a:1b, 2, and 3, respectively. Regarding liver injury, 29.4% had liver sinusoidal injury, whereas 11.7% had steatohepatitis. Meanwhile, all patients underwent postoperative chemotherapy.

CONCLUSION

mFOLFOX6 is safe and yields favorable therapeutic effects. The indication for liver resection after a certain waiting period is clinically significant.

Predictors of Lateral Pelvic Lymph Node Metastasis in Advanced Low Rectal Cancer Treated With Neoadjuvant Chemotherapy

BACKGROUND/AIM

This retrospective study used magnetic resonance imaging to identify clinicopathological predictors of lateral pelvic lymph node metastasis in patients with advanced low rectal cancer treated with neoadjuvant chemotherapy; only few such studies have been reported.

PATIENTS AND METHODS

Sixty-one patients with advanced low rectal cancer who underwent total mesorectal excision and lateral pelvic lymph node dissection after neoadjuvant chemotherapy between April 2013 and December 2019 were included in this study. Univariate and multivariate analyses were used to analyze the relationship between lateral pelvic lymph node metastasis and clinicopathological factors, such as lateral pelvic lymph node size, measured before and after neoadjuvant chemotherapy using magnetic resonance imaging.

RESULTS

The short-axis diameter of lateral pelvic lymph nodes before neoadjuvant chemotherapy (p=0.003, odds ratio: 2.898, 95% confidence interval=1.534-9.143) was the only identified independent preoperative predictor. Based on the receiver operating characteristic curve analysis, the cut-off value of the short-axis diameter of lateral pelvic lymph nodes before neoadjuvant chemotherapy was 6.8 mm. The area under the curve was 0.761 (95% confidence interval=0.723-0.932). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 77.8%, 72.1%, 53.8%, 88.6%, and 73.8%, respectively.

CONCLUSION

The preoperative predictor of lateral pelvic lymph node metastasis in advanced low rectal cancer treated with neoadjuvant chemotherapy was the short-axis diameter of lateral pelvic lymph nodes before neoadjuvant chemotherapy. When lateral pelvic lymph nodes with short-axis diameters above 6.8 mm are present, lateral pelvic lymph node dissection may be necessary.

Postoperative complications, bowel function, and prognosis in restorative proctocolectomy for ulcerative colitis-a single-center observational study of 320 patients

PURPOSE

To determine the selection criteria, postoperative complications, bowel function, and prognosis of stapled ileal pouch-anal anastomosis (IPAA) and hand-sewn IPAA for ulcerative colitis (UC).

METHODS

We defined our surgical indications and strategy, and compared the postoperative complications, bowel function, and prognoses between patients who underwent stapled and hand-sewn IPAA for UC at the Yokohama City University Medical Center between 2004 and 2017.

RESULTS

Among 320 patients enrolled, 298 patients underwent stapled IPAA while 22 underwent hand-sewn IPAA. There was no significant difference in the postoperative complications between the two groups. Regarding postoperative bowel function, stapled IPAA caused significantly less soiling (stapled vs hand-sewn: 9.1% vs 41.0%, odds ratio (OR) = 0.14, p < 0.0002), spotting (stapled vs hand-sewn: 23.2% vs 63.6%, OR = 0.17, p < 0.0001), and difficulty in distinguishing feces from flatus (stapled vs hand-sewn: 39.9% vs 63.6%, OR = 0.36, p < 0.026). No postoperative neoplasia was observed at the final follow-up in all patients.

CONCLUSION

In this study, there was no clear difference in the postoperative complications between stapled and hand-sewn IPAA, but stapled IPAA resulted in better postoperative bowel function. Postoperative oncogenesis from the residual mucosa is rare. However, future cancer risk remains; thus, careful follow-up is required.

Nucleic Acid Metabolizing Enzyme Levels Predict Chemotherapy Effects in Advanced and Recurrent Colorectal Cancer

Background:

Thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) predict the effects of fluoropyrimidine. However, the effects of FOLFOX therapy from the perspective of fluorouracil plus leucovorin (FL) remain underexplored. Hence, the relationship between mFOLFOX6 therapy (mFOLFOX6) and therapeutic efficacy was evaluated in patients with advanced/recurrent colorectal cancer (CRC).

Methods:

Correlations between TS and DPD and primary and metastatic lesions in recurrent CRC were analyzed. Univariate and multivariate analyses of TS and DPD in combination with response rate (RR), progression-free survival (PFS), and overall survival (OS) were performed.

Results:

A positive correlation between DPD and primary and metastatic lesions; correlations between TS and RR, DPD and RR, and PFS and OS; and significant differences for RR and DPD and TS, PFS and DPD, and OS and DPD were obtained.

Conclusion:

Nucleic acid metabolizing enzymes in primary lesions can be used to predict mFOLFOX6 efficacy in patients with recurrent CRC.

[A Case of Laparoscopic Ileus Release for Intestinal Obstruction Due to Small Intestinal Metastasis Four Years after Penile Cancer Surgery]

We report a rare case of metastatic small intestine cancer originating from penile cancer triggered by intestinal obstruction, with some review of the literature. The case was a 78-year-old man at the first visit. Partial penile resection was performed for penile cancer. Histopathological findings were squamous cell carcinoma, and the surgical margin was negative. The stage at the time of the first surgery was T2N0M0, Stage Ⅱ. He came to the hospital with a complaint of abdominal pain 4 years after the operation. He was diagnosed with intestinal obstruction and was treated medically. He underwent medical treatment for 12 days, but did not improve, so he underwent laparoscopic ileus release. Surgical findings showed a neoplastic lesion in the abdominal cavity, and the site was obstructed, and partial resection of the small intestine including the neoplastic lesion was performed. Pathological examination revealed small intestinal metastasis of penile cancer. Postoperative intestinal obstruction improved and he was discharged without complications. After discharge, he underwent systemic chemotherapy at an outpatient clinic, but died of the primary disease 181 days after intestinal obstruction.

Efficacy of active hexose correlated compound on survival of patients with resectable/borderline resectable pancreatic cancer: a study protocol for a double-blind randomized phase II study

Background

The prognosis of pancreatic ductal adenocarcinoma remains very poor. One possible reason for the short survival of patients with this disease is malnutrition, which can be present at the initial diagnosis, and continue after pancreatectomy. Then, it is important to improve nutritional status and to decrease adverse events during neoadjuvant and adjuvant chemotherapy. Active hexose correlated compound (AHCC) is a standardized extract of cultured Lentinula edodes mycelia, and is considered a potent biological response modifier in the treatment of cancer. To evaluate the survival impact of AHCC on the patients with pancreatic ductal adenocarcinoma, we plan to perform this trial.

Methods

This is a prospective multicenter phase II trial in patients with resectable/borderline resectable pancreatic ductal adenocarcinoma to investigate the efficacy of AHCC regarding survival. Patients will begin taking AHCC or placebo on the first day of neoadjuvant therapy. AHCC or placebo will be continued until 2 years after surgery. The primary endpoint will be 2-year disease-free survival. The secondary endpoints are the completion rate, dose intensity, and adverse event profile of preoperative chemotherapy; response rate to preoperative chemotherapy; rate of decrease in tumor marker (carbohydrate antigen 19-9, carcinoembryonic antigen) concentrations during preoperative chemotherapy; entry rate, completion rate, dose intensity, and adverse event profile of adjuvant chemotherapy; safety of the protocol therapy (adverse effect of AHCC); 2-year overall survival rate; and nutrition score before and after preoperative chemotherapy, and before and after adjuvant chemotherapy. We will enroll 230 patients, and the study involves eight leading Japanese institutions that are all high-volume centers in pancreatic surgery.

Discussion

AHCC is expected to function as a supportive food in patients with pancreatic ductal adenocarcinoma, to reduce the proportion of severe adverse events related to neoadjuvant chemotherapy, and to increase the completion proportion of multimodal treatments, resulting in improved survival.

Trial registration

The trial protocol has been registered in the protocol registration system at the Japan Registry of Clinical Trials (Trial ID: jRCTs051200029). At the time of the submission of this paper (October 2020), the protocol version is 2.0. The completion date is estimated to be November 2024.

Prognostic value of preoperative high-sensitivity modified Glasgow prognostic score in advanced colon cancer: a retrospective observational study

Background

Several studies have demonstrated that the preoperative Glasgow prognostic score (GPS) and modified GPS (mGPS) reflected the prognosis in patients undergoing curative surgery for colorectal cancer. However, there are no reports on long-term prognosis prediction using high-sensitivity mGPS (HS-GPS) in colorectal cancer. Therefore, this study aimed to calculate the prognostic value of preoperative HS-GPS in patients with colon cancer.

Methods

A cohort of 595 patients with advanced resectable colon cancer managed at our institution was analysed retrospectively. HS-GPS, GPS, and mGPS were evaluated for their ability to predict prognosis based on overall survival (OS) and recurrence-free survival (RFS).

Results

In the univariate analysis, HS-GPS was able to predict the prognosis with significant differences in OS but was not superior in assessing RFS. In the multivariate analysis of the HS-GPS model, age, pT, pN, and HS-GPS of 2 compared to HS-GPS of 0 (2 vs 0; hazard ratio [HR], 2.638; 95% confidence interval [CI], 1.046–6.650; P = 0.04) were identified as independent prognostic predictors of OS. In the multivariate analysis of the GPS model, GPS 2 vs 0 (HR, 1.444; 95% CI, 1.018–2.048; P = 0.04) and GPS 2 vs 1 (HR, 2.933; 95% CI, 1.209–7.144; P = 0.017), and in that of the mGPS model, mGPS 2 vs 0 (HR, 1.51; 95% CI, 1.066–2.140; P = 0.02) were independent prognostic predictors of OS. In each classification, GPS outperformed HS-GPS in predicting OS with a significant difference in the area under the receiver operating characteristic curve. In the multivariate analysis of the GPS model, GPS 2 vs 0 (HR, 1.537; 95% CI, 1.190–1.987; P = 0.002), and in that of the mGPS model, pN, CEA were independent prognostic predictors of RFS.

Conclusion

HS-GPS is useful for predicting the prognosis of resectable advanced colon cancer. However, GPS may be more useful than HS-GPS as a prognostic model for advanced colon cancer.

[A Case of Preoperatively Diagnosed Early Cystic-Duct Carcinoma]

A 88-year-old man presented with abdominal discomfort. Computed tomography(CT)images showed gallbladder tumor, and the patient was referred to our hospital. In addition to the above, CT images showed a tense gallbladder and EUS showed papillary raised lesions mainly from the cystic duct to the gallbladder neck. Based on the above, we diagnosed cystic duct cancer and performed full-thickness cholecystectomy, extrahepatic bile duct resection, regional lymph node dissection at our department. Macroscopic findings of the resected specimen showed a Villous ridge in the cystic duct. Histopathological findings revealed well-differentiated adenocarcinoma with an irregular papillary structure centered on the cystic duct. The depth of invasion remained within the epithelium, and a diagnosis of primary early cystic duct cancer was made. Primary cystic duct cancer is a relatively rare disease and often does not lead to preoperative diagnosis. This time, we experienced a case in which cystic duct cancer was diagnosed preoperatively due to complaints of abdominal discomfort and could be surgically resected.

Possibility for avoidance of urgent nighttime operations for acute appendicitis in a regional core university hospital

INTRODUCTION

In recent years, a shortage of surgeons and anesthesiologists, particularly in regional hospitals, has become a social issue in Japan. In such hospitals, urgent surgery at night has been performed with difficulty. Therefore, we retrospectively assessed the outcomes of appendectomies for the patients visited at nighttime in our hospital categorized as a local university hospital.

METHODS

A retrospective review was conducted on 82 patients of acute appendicitis presented to our hospital between 5:30 p.m. to 8:30 a.m., between January 2014 and April 2019. We compared patients who underwent urgent nighttime appendectomy (group A) and patients who underwent appendectomy during the daytime, or so-called short interval appendectomy (group B). The evaluated factors were preoperative characteristics (age, sex, body mass index, cardiopulmonary complications, laboratory data, body temperature, presence of the Blumberg sign, and CT findings), operation characteristics, and postoperative characteristics (surgical-site infection [SSI], complications, and length of hospital stay).

RESULTS

Patients in group A were significantly younger than patients in group B. Patients in group A were significant more likely to experience an SSI.

DISCUSSION

Patients diagnosed with acute appendicitis during the nighttime can undergo short interval appendectomy, which leads to a decreased risk of SSI, has no effect on length of hospital stay after surgery, and lessens medical staff burden.

CD15+ Bone Marrow-derived Cells Are Regulators of Immune Response in ARG1-producing Colorectal Cancer Cells

BACKGROUND/AIM

Bone marrow-derived cells regulate the antitumor functions of tumor infiltrating lymphocytes (TILs) through arginase 1 (ARG1)-dependent metabolism. This study examines which ARG1-producing lineage is responsible for the inhibitory function of TILs.

MATERIALS AND METHODS

Multiplexed immunohistochemistry was performed for CD11b, CD163, CD68, and CD15, together with ARG1 expression and CD3⁺ TIL infiltration estimation in human colorectal cancer specimens.

RESULTS

Stratified survival analyses demonstrated that a large number of CD3⁺ TILs is a favorable prognostic factor in subgroups with a high level of ARG1⁺ infiltration and in the subgroup with a low level of ARG1^- CD15⁺ infiltration. Calculation of the ARG1⁺/ARG1^- ratio demonstrated that CD3⁺ TIL infiltration was prognostic in the subgroup with a low ARG1⁺/ARG1^- ratio for CD15⁺ cells, contrary to other lineages.

CONCLUSION

Tumor infiltrating CD15⁺ cells, the majority of which show polymorphonuclear features, are responsible for the ARG1-dependent T-cell dysfunction in human colorectal cancer.

[A Case of Combined Modality Therapy for Progressive Esophagus Cancer with Perforation Due to Preoperative Chemotherapy]

A nearby doctor sensed incongruity in deglutition as a chief complaint from a 56-year-old man. A middle intrathoracic esophagus cancer was subsequently diagnosed and referred to our department. We started FP therapy based on the preoperative chemotherapy guidelines, but perforation of esophageal cancer developed. We conducted chest drainage, and attempted to improve the patient's overall status with antibiotic medical treatment and hyperalimentation; single-stage operations were performed. As tumor invaded the left pleura, surgery occurred for R2 resection of the left lung. Subsequently, we started nivolumab therapy because we give DCF therapy and detected a liver metastasis and we continue it now and survive.

The Tokyo 2020 terminology of liver anatomy and resections: Updates of the Brisbane 2000 system

BACKGROUND

The Brisbane 2000 Terminology for Liver Anatomy and Resections, based on Couinaud's segments, did not address how to identify segmental borders and anatomic territories of less than one segment. Smaller anatomic resections including segmentectomies and subsegmentectomies, have not been well defined. The advent of minimally invasive liver resection has enhanced the possibilities of more precise resection due to a magnified view and reduced bleeding, and minimally invasive anatomic liver resection (MIALR) is becoming popular gradually. Therefore, there is a need for updating the Brisbane 2000 system, including anatomic segmentectomy or less. An online "Expert Consensus Meeting: Precision Anatomy for Minimally Invasive HBP Surgery (PAM-HBP Surgery Consensus)" was hosted on February 23, 2021.

METHODS

The Steering Committee invited 34 international experts from around the world. The Expert Committee (EC) selected 12 questions and two future research topics in the terminology session. The EC created seven tentative definitions and five recommendations based on the experts' opinions and the literature review performed by the Research Committee. Two Delphi Rounds finalized those definitions and recommendations.

RESULTS

This paper presents seven definitions and five recommendations regarding anatomic segmentectomy or less. In addition, two future research topics are discussed.

CONCLUSIONS

The PAM-HBP Surgery Consensus has presented the Tokyo 2020 Terminology for Liver Anatomy and Resections. The terminology has added definitions of liver anatomy and resections that were not defined in the Brisbane 2000 system.

Minimally invasive anatomic liver resection: Results of a survey of world experts

BACKGROUND

Although the number of minimally invasive liver resections (MILRs) has been steadily increasing in many institutions, minimally invasive anatomic liver resection (MIALR) remains a complicated procedure that has not been standardized. We present the results of a survey among expert liver surgeons as a benchmark for standardizing MIALR.

METHOD

We administered this survey to 34 expert liver surgeons who routinely perform MIALR. The survey contained questions on personal experience with liver resection, inflow/outflow control methods, and identification techniques of intersegmental/sectional planes (IPs).

RESULTS

All 34 participants completed the survey; 24 experts (70%) had more than 11 years of experience with MILR, and over 80% of experts had performed over 100 open resections and MILRs each. Regarding the methods used for laparoscopic or robotic anatomic resection, the Glissonean approach (GA) was a more frequent procedure than the hilar approach (HA). Although hepatic veins were considered essential landmarks, the exposure methods varied. The top three techniques that the experts recommended for identifying IPs were creating a demarcation line, indocyanine green negative staining method, and intraoperative ultrasound.

CONCLUSION

Minimally invasive anatomic liver resection remains a challenging procedure; however, a certain degree of consensus exists among expert liver surgeons.

[Examination of Prognostic Factors for Elderly Colon Cancer]

Elderly people tend to be in poor general condition and have many comorbidities. It has been reported that these things may be associated with postoperative recurrence and the increase in mortality rate. In order to evaluate their distinctive comorbidity and immunocompetence, we analyzed the covariates including Charlson comorbidity index(CCI), performance status(PS), and immune-nutrient factors. We retrospectively examined 175 cases of radical resection of colon cancer aged 75 years or older performed in our department from January 2000 to December 2014. There were 133/29/11/2 patients for PS 0/1/2/3, respectively. The median CCI was 4.0(range: 1-11). In the multivariate analysis for overall survival(OS), there was a significant difference in PS, BMI, N-factor, venous invasion, pathological stage, neutrophil-to-lymphocyte rate (NLR), lymphocyte-to-monocyte rate(LMR), and modified Glasgow prognostic scale(mGPS). In the multivariate analysis for relapse-free survival(RFS), there was a significant difference in gender, T-factor, N-factor, pathological stage, collected lymph nodes, NLR, LMR, and mGPS. It was suggested that their preoperative general and nutritional conditions can lead to the good oncologic outcomes for the elderly patients in colon cancer.

[A Case of Percutaneous Transhepatic Duodenal Drainage for Duodenal Stump Suture Failure after Gastrectomy]

79-year-old man underwent laparoscopic distal gastrectomy with early gastric cancer 0-Ⅱc lesion on the greater curvature side of the lower body of the gastric body on gastric cancer screening. On the 10th day after the operation, abdominal pain and fever were observed, and CT revealed suture failure and intra-abdominal abscess. Partial gastrectomy and Roux- en-Y reconstruction were performed in emergency surgery, but duodenal stump suture failure was observed on the third day of reoperation. For duodenal stump suture failure, a catheter was placed in the duodenum by applying PTCD technology, and drainage of the bile duct and duodenal contents was performed, and conservative healing was successful. Duodenal stump suture failure after Roux-en-Y reconstruction is intractable and can sometimes result in death with severe infection and intra-abdominal hemorrhage. Here, we report a case in which duodenal stump suture failure was completely cured by percutaneous transhepatic duodenal drainage, with some literary consideration.

[An Early Gastric Cancer with Sarcoid Reactions of the Regional Lymph Nodes]

The patient was a 73-year-old male who was referred to our hospital for detailed examination because computed tomography(CT)revealed lymph node swelling. Upper gastrointestinal endoscopy revealed a 0-Ⅱc lesion in the greater curvature of the middle gastric body. The periphery of the lesion site was not reached using endoscopy. CT revealed lymph node swelling, but positron emission tomography(PET)-CT did not show abnormal accumulation in any area other than the lesion site involving the lymph nodes. Under a diagnosis of cT2N0M0, Stage Ⅰ tumor, total gastrectomy via laparotomy and lymph node dissection(D2+No.10)was performed. The histopathological diagnosis suggested early gastric cancer pT1b (SM)N0M0, Stage ⅠA. Although lymph node metastasis was not observed, the outgrowth of non-caseating epithelioid cell granulomas was observed in all lymph nodes. There was no granulomatous lesion at any other site, including the lung, leading to a diagnosis of sarcoid reactions. The"sarcoid reaction"refers to non-caseating epithelioid cell granuloma formation in a local area or the regional lymph nodes of a malignant tumor through reactions to extraneous foreign bodies in the absence of the general condition or signs as sarcoidosis. Sarcoid reactions to early gastric cancer are rare. In this study, we report a patient with early gastric cancer who showed sarcoid reactions of the regional lymph nodes and review the literature.

[A Case of Elective Laparoscopic Resection for Sigmoid Colon Cancer with Irreducible Intussusception]

An 85-year-old man was hospitalized for a right greater trochanteric fracture. Rectal intussusception was found by diagnostic imaging but left untreated because of minor gastrointestinal symptoms. As a result of work-up for persistent mucous stool, he was diagnosed with sigmoid colon cancer with intussusception. The intussusception could not be reduced during barium enema examination but could undergo elective laparoscopic surgery with a good postoperative course. Adult intussusception may be asymptomatic and require no emergency treatment. In such a case, elective surgery can be performed. Many facilities employ laparotomy as a standard of care for intussusception. With the recent technological advances in endoscopic surgeries, laparoscopic surgery can be considered as a treatment option.

[A Case of Gastrointestinal Stromal Tumor(GIST)of the Sigmoid Colon with Early Colon Cancer]

A 67-year-old male patient was referred to our department for fecal occult blood in March 2019. In April, lower intestinal endoscopic examination revealed a 25-mm pedunculated polyp in the sigmoid colon. Endoscopic mucosal resection was then performed. The pathological diagnosis was tub1-tub2 with an invasion depth of pT1b 3,000 μm, and ly0 and v1 vascular invasion. The tumor marker levels were normal, with CEA of 1.1 ng/mL and CA19-9 of 13.9 U/mL. An additional laparoscopic low anterior resection and D2 dissection were performed in June. After the endoscopic mucosal resection, pathologic examination revealed densely hyperplastic spindle cells arranged in bundles at the proper muscular layer of the scar site. There was no lymph node metastasis. On immunostaining, the lesion tested positive for c-kit, CD34, and DOG1, but negative for desmin, SMA, and S-100, with a MIB-1 index of 2%. The patient was diagnosed with very low risk gastrointestinal stromal tumor(GIST). We encountered a rare case of early sigmoid colon cancer, complicated by sigmoid colon GIST.

[A Case of Isolated Metachronous Splenic Metastasis after Rectal Cancer Surgery]

A 50-year-old woman underwent laparotomic anterior resection(D3)and total hysterectomy with bilateral adnexectomy (type 2, 3.0×4.5 cm, pT4a[SE], N1a, M1c2[ovary and peritoneum], H0, P1, PUL0, stage Ⅳc, tub2>por, Cur B)for ovarian metastasis from rectal cancer in June 20XX. During the outpatient visit in May, 2 years and 11 months after surgery, a splenic tumor was found on abdominal contrast-enhanced CT, without distant metastasis in other organs. In July 20XX, laparoscopic splenectomy was performed for suspected splenic metastasis of rectal cancer. The specimen of the resected tumor showed pathological findings consistent with metastasis of rectal cancer. Currently, the patient is being followed up without any sign of recurrence. Herein, we report a rare case of isolated metachronous splenic metastasis, whose associated prognosis might be improved by surgical treatment, in reference to the literature.

Novel Therapeutic Method for Unresectable Pancreatic Cancer-The Impact of the Long-Term Research in Therapeutic Effect of High-Intensity Focused Ultrasound (HIFU) Therapy

High-intensity focused ultrasound (HIFU) is a novel advanced therapy for unresectable pancreatic cancer (PC). HIFU therapy with chemotherapy is being promoted as a novel method to control local advancement by tumor ablation. We evaluated the therapeutic effects of HIFU therapy in locally advanced and metastatic PC. PC patients were treated with HIFU as an optional local therapy and systemic chemotherapy. The FEP-BY02 (Yuande Bio-Medical Engineering) HIFU device was used under ultrasound guidance. Of 176 PC patients, 89 cases were Stage III and 87 were Stage IV. The rate of complete tumor ablation was 90.3%, while that of symptom relief was 66.7%. The effectiveness on the primary lesions were as follows: complete response (CR): n = 0, partial response (PR): n = 21, stable disease (SD): n = 106, and progressive disease (PD): n = 49; the primary disease control rate was 72.2%. Eight patients underwent surgery. The median survival time (MST) after diagnosis for HIFU with chemotherapy compared to chemotherapy alone (100 patients in our hospital) was 648 vs. 288 days (p < 0.001). Compared with chemotherapy alone, the combination of HIFU therapy and chemotherapy demonstrated significant prolongation of prognosis. This study suggests that HIFU therapy has the potential to be a novel combination therapy for unresectable PC.

Clinicopathological Features of Remnant Gastric Cancer After Gastrectomy

BACKGROUND

Remnant gastric cancer (RGC) encompasses all cancers arising from the remnant stomach. Various studies have reported on RGC and its prognosis, but no consensus on its surgical treatment and postoperative management has been reached. Moreover, the correlation between the clinicopathological characteristics and long-term outcomes of RGC remains unclear. This study investigated the clinicopathological factors associated with the long-term survival of RGC patients.

METHODS

The medical records (March 1993-September 2020) of 104 RGC patients from Tokyo Medical University Hospital database were analyzed. Of these 104 patients, the medical records of 63 patients who underwent surgical curative resection were analyzed using R. Kaplan-Meier plots of cumulative incidence of RGC were made. Differences in survival rates were compared using the log-rank test. Prognostic factors were analyzed using multivariate Cox regression analysis (P < .05).

RESULTS

Of the 104 RGC patients, 63 underwent total remnant stomach excision. The median time from the first surgery to the total excision was 10 years. The 5-year survival rate of the 63 RGC patients was .55 ((95% CI); .417-.671). The clinicopathological factors that were significantly associated with the long-term outcome of the RGC patients were tumor diameter (≥3.5 cm), presence or absence of combined resection of multiple organs, tumor invasion (deeper than T2), TNM stage, and postoperative morbidity. The multivariate Cox regression analysis showed that tumor invasion depth was the only independent prognostic factor for RGC patients [HR (95% CI): 5.49 (2.629-11.5), P ≤ .005].

CONCLUSIONS

Among prognostic factors, tumor invasion depth was the only independent factor affecting RGC's long-term outcome.

International expert consensus on precision anatomy for minimally invasive pancreatoduodenectomy: PAM-HBP surgery project

BACKGROUND

The anatomical structure around the pancreatic head is very complex and it is important to understand its precise anatomy and corresponding anatomical approach to safely perform minimally invasive pancreatoduodenectomy (MIPD). This consensus statement aimed to develop recommendations for elucidating the anatomy and surgical approaches to MIPD.

METHODS

Studies identified via a comprehensive literature search were classified using the Scottish Intercollegiate Guidelines Network method. Delphi voting was conducted after experts had drafted recommendations, with a goal of obtaining >75% consensus. Experts discussed the revised recommendations with the validation committee and an international audience of 384 attendees. Finalized recommendations were made after a second round of online Delphi voting.

RESULTS

Three clinical questions were addressed, providing six recommendations. All recommendations reached at least a consensus of 75%. Preoperatively evaluating the presence of anatomical variations and superior mesenteric artery (SMA) and superior mesenteric vein (SMV) branching patterns was recommended. Moreover, it was recommended to fully understand the anatomical approach to SMA and intraoperatively confirm the SMA course based on each anatomical landmark before initiating dissection.

CONCLUSIONS

MIPD experts suggest that surgical trainees perform resection based on precise anatomical landmarks for safe and reliable MIPD.

Expert Consensus Guidelines: How to safely perform minimally invasive anatomic liver resection

BACKGROUND

The concept of minimally invasive anatomic liver resection (MIALR) is gaining popularity. However, specific technical skills need to be acquired to safely perform MIALR. The "Expert Consensus Meeting: Precision Anatomy for Minimally Invasive HBP Surgery (PAM-HBP Surgery Consensus)" was developed as a special program during the 32nd meeting of the Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHBPS).

METHODS

Thirty-four international experts gathered online for the consensus. A Research Committee performed a comprehensive literature review, classifying studies according to the Scottish Intercollegiate Guidelines Network method. Based on the literature review and experts' opinions, tentative recommendations were drafted and circulated among experts using online Delphi Rounds. Finally, formulated recommendations were presented online in the Expert Consensus Meeting of the JSHBPS on February 23rd, 2021. The final recommendations were validated and finalized by the 2nd Delphi Round in May 2021.

RESULTS

Seven clinical questions were selected, and 22 recommendations were formulated. All recommendations reached more than 85% consensus among experts at the final Delphi Round.

CONCLUSIONS

The Expert Consensus Meeting for safely performing MIALR has presented a set of clinical guidelines based on available literature and experts' opinions. We expect these guidelines to have a favorable effect on the safe implementation and development of MIALR.

Significance of Radiofrequency Ablation for Unresectable Colorectal Cancer With Liver Metastases

BACKGROUND/AIM

We aimed to investigate the prognosis of patients who received radiofrequency ablation (RFA) for liver metastases of unresectable colorectal cancer (CRC).

PATIENTS AND METHODS

We retrospectively compared 147 patients treated for CRC liver metastases, who underwent RFA (n=26), resection (n=92), and chemotherapy (n=29) between 2001 and 2021.

RESULTS

RFA and chemotherapy were performed for unresectable or non-operable cases, and resection was performed for suitable cases. The median overall survival (OS) was 44.9, 49.5, and 11.6 months for patients who underwent RFA, resection, and chemotherapy, respectively. RFA led to a significantly shorter OS compared to resection (p=0.027) but to a longer OS compared to chemotherapy (p=0.003). The 5-year survival rates were 34.6% and 42.4% for patients who underwent RFA and resection, respectively (p=0.508).

CONCLUSION

RFA has the potential to achieve long-term survival or radical cure, even for unresectable or non-operable cases of CRC with liver metastasis.

A Novel Predictive Model for Anastomotic Leakage in Colorectal Cancer Using Auto-artificial Intelligence

AIM

Anastomotic leakage (AL) in left-sided colorectal cancer is a serious complication, with an incidence rate of 6-18%. We developed a novel predictive model for AL in colorectal surgery with double-stapling technique (DST) anastomosis using auto-artificial intelligence (AI).

PATIENTS AND METHODS

A total of 256 patients who underwent curative surgery for left-sided colorectal cancer between 2017 and 2021 were included. In addition to conventional clinicopathological factors, we included the type of circular stapler using DST, conventional double-row circular stapler (DCS) or EEA™ circular stapler with Tri-Staple™ technology, 28 mm Medium/Thick (Covidien, New Haven, CT, USA) which had triple-row circular stapler (TCS) as a covariate. Auto-AI software Prediction One (Sony Network Communications Inc.) was used to predict AL with 5-fold cross validation. Predictive accuracy was assessed using the area under the receiver operating characteristic curve. Prediction One also evaluated the 'importance of variables' (IOV) using a method based on permutation feature importance.

RESULTS

The area under the curve of the AI model was 0.766. The type of circular stapler used was the most influential factor contributing to AL (IOV=0.551).

CONCLUSION

This auto-AI predictive model demonstrated an improvement in accuracy compared to the conventional model. It was suggested that use of a TCS may contribute to a reduction in the AL rate.

National survey of hepatobiliary and pancreatic surgery in hemophilia patients in Japan

BACKGROUND

Approximately 8300 hemophiliacs are registered in Japan, but no comprehensive reports on hepatobiliary and pancreatic surgery (HBPS) have been conducted. This report investigates the current status of HPBS in hemophilia patients in Japan.

METHODS

The subjects were hemophiliac patients seen between January 1 2007, and December 31 2017, at facilities participating in this study among the facilities for performing high-difficulty cases nationwide designated by the Japanese Society for HBPS. A retrospective examination of short-term outcomes in 49 cases was conducted to assess patient background, disease, surgical procedure, and complications.

RESULTS

The types of hemophilia were A: 43 cases, B: four cases, and von Willebrand disease: two cases (hemophilia severity: mild 32, moderate seven, severe 10). The target malignant diseases for surgery were hepatocellular carcinoma (HCC) in 20 cases, intrahepatic cholangiocellular carcinoma (CCC) in four cases, combined HCC-CCC in two cases, hilar CCC in two cases, and pancreatic cancer in four cases. As for the surgical procedure, limited resection (subsegmentectomy and partial hepatectomy) was performed in 16 cases of HCC even with normal liver function tests. Pancreaticoduodenectomy and distal pacreatectomy were performed for pancreatic cancers as in the standard procedure. Postoperative complications were postoperative bleeding in two cases after hepatectomy and one after pancreatectomy in one case. When compared with Japanese National Clinical Data base, the complication rates after hepatectomy and pancreatectomy were not conspicuous in hemophilic patients.

CONCLUSIONS

As long as they are performed in qualified centers, complication rate is not increased in hemophilic patients undergoing HBPS.

International Expert Consensus on Precision Anatomy for minimally invasive distal pancreatectomy: PAM-HBP Surgery Project

BACKGROUND

Surgical views with high resolution and magnification have enabled us to recognize the precise anatomical structures that can be used as landmarks during minimally invasive distal pancreatectomy (MIDP). This study aimed to validate the usefulness of anatomy-based approaches for MIDP before and during the Expert Consensus Meeting: Precision Anatomy for Minimally Invasive HBP Surgery (February 24, 2021).

METHODS

Twenty-five international MIDP experts developed clinical questions regarding surgical anatomy and approaches for MIDP. Studies identified via a comprehensive literature search were classified using Scottish Intercollegiate Guidelines Network methodology. Online Delphi voting was conducted after experts had drafted the recommendations, with the goal of obtaining >75% consensus. Experts discussed the revised recommendations in front of the validation committee and an international audience of 384 attendees. Finalized recommendations were made after a second round of online Delphi voting.

RESULTS

Four clinical questions were addressed, resulting in 10 recommendations. All recommendations reached at least a 75% consensus among experts.

CONCLUSIONS

The expert consensus on precision anatomy for MIDP has been presented as a set of recommendations based on available evidence and expert opinions. These recommendations should guide experts and trainees in performing safe MIDP and foster its appropriate dissemination worldwide.

The First International Expert Consensus Meeting on Precision Anatomy for Minimally Invasive Hepato-Biliary-Pancreatic Surgery during JSHBPS 2020 in Tokyo: PAM-HBP Surgery Project

Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHBPS) which was established in 1993 has been working with the mission to develop general academic research and knowledge on hepato-biliary-pancreatic (HBP) surgery and, further, to pursue the patient safety and patient's best interest in HBP surgery with the cooperated work of international HBP surgeons.

Preoperative Lymphocyte-to-Monocyte Ratio in the Prognostication of Advanced Resectable Colon Cancer: a Retrospective Observational Study

Lymphocyte-to-monocyte ratio (LMR) has been reported as a biomarker for predicting the prognosis of colorectal cancer. However, the clinical usefulness of LMR requires detailed research, which can contribute to better therapeutic strategies. A cohort of 554 patients with resectable advanced colon cancer in our institution was analyzed retrospectively. An analysis of stages II and III resectable advanced colon cancer was performed. LMR was useful for predicting overall survival (OS) and relapse-free survival (RFS). The ROC curve revealed an LMR value of 2.77 as a cutoff for OS. A high LMR was an independent prognostic factor and was associated with a high hazard ratio (HR) in all cases for OS (HR = 0.530, 95% confidence interval (CI) = 0.334-0.842, p = 0.007). A high LMR was not an independent prognostic factor in stage II cases but was a predictor with the strongest association with prognosis in patients with stage III cases for OS (HR = 0.383, 95% CI = 0.160-0.915, p = 0.031). LMR is a strong predictor of prognosis in patients with stage III colon cancer and may be useful in postoperative treatment options.

Is GLP-1 insufficiency a coronary risk factor? A multicenter observational study, BOREAS-CAD2

Background and aim

Glucagon-like peptide-1 (GLP-1) regulates insulin secretion and also affords pleiotropic effects including protective effects on blood vessels. Multiple factors regulate GLP-1 secretion after meals, but a group of apparently healthy subjects showed blunted responses of GLP-1 secretion in our previous study. In this study, we examined the possibility that the reduced capacity of GLP-1 secretion is associated with increased extent of coronary artery stenosis in non-diabetic patients.

Methods and results

Non-diabetic patients who were admitted for coronary angiography without a history of coronary interventions were enrolled. Coronary artery stenosis was quantified by Gensini score (GS), and GS ≥10 was used as an outcome variable based on results of earlier studies indicating its predictive value for cardiovascular events. The patients (mean age, 66.5±8.8 years; 71% males, n=173) underwent oral 75 g-glucose tolerant tests for determination of glucose, insulin and active GLP-1 levels. The area under the curve of plasma active GLP-1 (AUC-GLP-1) was determined as an index of GLP-1 secretion capacity. AUC-GLP-1 was not correlated with fasting glucose, AUC-glucose, serum lipids, indices of insulin sensitivity or estimated glomerular filtration rate. In multivariate logistic regression analysis for GS ≥10, AUC-GLP-1 &lt; median, age and hypertension were selected as explanatory variables, though fasting GLP-1 level was not selected.

Conclusion

The findings indicate significant association of reduced GLP-1 secretion capacity with increased extent of coronary artery stenosis in non-diabetic patients. A causal relationship between change in GLP-1 secretion capacity and coronary stenosis remains to be examined by a longitudinal study

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): This study was supported in part by a research grant from Investigator-Initiated Studies Program of Merck Sharp & Dohme Corp./MSD K.K.

Sporadic intra-abdominal desmoid tumor with a very unusual onset: two case reports

Background

Intra-abdominal desmoid tumors are rare soft tissue tumors that arise mainly in the mesentery and pelvis. Their etiology may include genetic mutations, estrogen-associated changes after childbirth, and mechanical factors such as a history of abdominal surgery. However, there are cases of intra-abdominal desmoid tumors that develop in the absence of such causes. Since they are rare, diagnosis is often difficult based on clinical findings. We encountered two cases of patients with sporadic intra-abdominal desmoid tumors with a very unusual onset and contrasting features.

Case presentation

The first patient was a 51-year-old asian man who presented with sudden onset of abdominal pain. He was referred to our department because of a giant tumor detected on abdominal ultrasonography. Imaging revealed a 19-cm tumor with internal tumoral hemorrhage; however, no definitive diagnosis was made. Tumor resection was performed for diagnostic and therapeutic purposes. The second patient was a 41-year-old asian man, and right hydronephrosis was detected on abdominal ultrasonography during a periodic medical checkup. We diagnosed invasion of the primary mesenteric tumor into the right ureter using diagnostic imaging and performed ileocecal resection with partial right ureteral resection for a definitive diagnosis and therapeutic purposes. Although the tumors of both patients had developed from the ileal mesentery, the tumors were substantially different from each other based on their imaging findings, macroscopic morphology, and progression pattern. Meanwhile, they showed similar pathological characteristics. Both consisted of bundles of collagen fibrils of spindle-shaped fibroblasts with low cell atypia. Moreover, they were diagnosed as desmoid tumors using positive immunohistochemical staining for β-catenin.

Conclusions

Neither patient had susceptibility factors for desmoid tumors, and to our knowledge, there have been very few reports to date of intra-abdominal desmoid tumors that were diagnosed because of acute abdominal pain caused by tumoral hemorrhage or asymptomatic obstructive uropathy. Furthermore, it is clinically interesting that the two patients showed contrasting progression patterns and imaging findings. Intra-abdominal desmoid tumors are rare and may present with various symptoms and findings similar to those observed in our patients. Diagnosis therefore requires experience and knowledge that is not bound by preconceptions.

Neutrophil-to-lymphocyte Ratio as a Prognostic Factor for Colon Cancer in Elderly Patients: A Propensity Score Analysis

AIM

This study aimed to evaluate the prognostic value of neutrophil-to-lymphocyte ratio (NLR) in elderly patients with Stage I-III colon cancer for long-term oncologic outcomes.

PATIENTS AND METHODS

We retrospectively reviewed 175 patients aged >75 years who underwent radical surgery for Stage I-III colon cancer between 2000 and 2015 at our institute. Overall survival (OS), cancer-specific survival (CSS), and relapse-free survival (RFS) were evaluated according to NLR values using propensity score analysis. Patients were allocated to the higher NLR (H-NLR) or the lower NLR (L-NLR) group with a cut-off value of 2.3, based on receiver operating characteristic curve.

RESULTS

Before case matching, there were significant differences between the two groups for CSS (p=0.023) and RFS (p<0.001), but not for OS (p=0.069). Similar results were obtained after case matching, with significant differences observed for CSS (p=0.003) and RFS (p=0.027), but not for OS (p=0.145).

CONCLUSION

NLR may be a prognostic factor in elderly patients with colon cancer.

A Novel Prediction Model for Colon Cancer Recurrence Using Auto-artificial Intelligence

BACKGROUND/AIM

We aimed to develop a novel recurrence prediction model for stage II-III colon cancer using simple auto-artificial intelligence (AI) with improved accuracy compared to conventional statistical models.

PATIENTS AND METHODS

A total of 787 patients who had undergone curative surgery for stage II-III colon cancer between 2000 and 2018 were included. Binomial logistic regression analysis was used to calculate the effect of variables on recurrence. The auto-AI software 'Prediction One' (Sony Network Communications Inc.) was used to predict recurrence with the same dataset used for the conventional statical model. Predictive accuracy was assessed by the area under the receiver operating characteristic curve (AUC).

RESULTS

The AUC of the multivariate model was 0.719 (95%CI=0.655-0.784), whereas that of the AI model was 0.815, showing a significant improvement.

CONCLUSION

This auto-AI prediction model demonstrates improved accuracy compared to the conventional model. It could be constructed by clinical surgeons who are not familiar with AI.

Carbohydrate Antigen 19-9 Is an Invasive Malignancy Preoperative Prognostic Factor for Intraductal Papillary Mucinous Neoplasms

INTRODUCTION

This study aimed to determine the preoperative clinicophysiological and postoperative clinicopathological predictors of malignancy in patients with intraductal papillary mucinous neoplasm (IPMN).

METHODS

This was a retrospective observational study. We included 121 patients (73 men and 48 women; mean age: 68.7 years) who had undergone pancreatic resection for IPMN between 2007 and 2018. These patients were grouped into invasive carcinoma (IPMN-INV, N = 21) and low/high-grade IPMN (IPMN-LG/HG, N = 100) groups. Univariate and multivariate analyses of clinicophysiological parameters were carried out. These parameters were also compared between the IPMN-INV/HG (N = 53) and IPMN-LG (N = 68) groups. Survival analyses according to macroscopic type and IPMN subtypes were performed.

RESULTS

On univariate analysis, age (p = 0.038), carbohydrate antigen (CA) 19-9 (p < 0.001), IPMN macroscopic type (p = 0.001), IPMN subtype (p < 0.001), pancreatic duct diameter (p < 0.001), and mural nodule (p = 0.042), between IPMN-INV and IPMN-LG/HG were found to be significant prognostic factors of malignancy. CA 19-9 was found to be an independent prognostic factor of IPMN malignancy on multivariate analysis (p = 0.035). The 1-, 3-, and 5-year overall survival (OS) rates of the IPMN-INV and IPMN-LG/HG groups were 94.4/100%, 94.4/100%, and 67.2/100%, respectively. The OS rate in the IPMN-LG/HG group was significantly higher than that in the IPMN-INV group (p < 0.001). On univariate analysis, platelet (p = 0.043), CA 19-9 (p = 0.039), prognostic nutritional index (p = 0.034), platelet/lymphocyte ratio (p = 0.01), IPMN macroscopic type (p < 0.001), IPMN subtype (p < 0.001), pancreatic duct diameter (p = 0.036), and mural nodule (p = 0.032) between IPMN-INV/HG and IPMN-LG were found to be significant prognostic factors of malignancy. On multivariate analysis, CA 19-9 was found to be an independent prognostic factor (p = 0.042) between IPMN-INV/HG and IPMN-LG of malignancy. The 1-, 3-, and 5-year OS rates of the IPMN-INV/HG and IPMN-LG groups were 97.9/100%, 97.9/100%, and 82.6/100%, respectively. The OS rate was significantly higher in the IPMN-LG group than in the IPMN-INV/HG group (p = 0.03). No significant differences in survival were observed in patients with macroscopic tumors (p= 0.544).

CONCLUSION

CA 19-9 is an independent invasive malignancy predictor of IPMN.

Predictive Factors of Postendoscopic Submucosal Dissection Electrocoagulation Syndrome and the Utility of Computed Tomography Scan after Esophageal Endoscopic Submucosal Dissection

BACKGROUND/AIMS

Recently, postendoscopic submucosal dissection electrocoagulation syndrome (PEECS) has attracted attention. However, the criteria for computed tomography (CT) scanning following esophageal endoscopic submucosal dissection (ESD) are unclear. In this study, we aimed to identify the predictive factors of PEECS and the usefulness of CT scanning after esophageal ESD.

METHODS

A total of 245 lesions in 223 patients who underwent esophageal ESD between February 2008 and October 2018 were retrospectively analyzed. Patients with double cancers, those who experienced procedural accidents, such as aspiration pneumonitis or perforation, and those who were unable to undergo CT were excluded from the study. PEECS evaluation items included body temperature (≤37.7°C = 1 point, ≥37.8°C = 2 points), white blood cell count (<10,800/μL = 1 point, ≥10,800/μL = 2 points), and chest pain (numerical rating scale [NRS] ≤4 = 1 point, NRS ≥5 = 2 points). Scores of ≥5 points were categorized as the PEECS-positive group, and scores of ≤4 points were categorized as the PEECS-negative group. The degree of mediastinal emphysema on CT was stratified into 5 grades, in which grades 0 and 1 were considered as the "low-grade" group, and grades 2, 3, and 4 were considered as the "high-grade" group. We analyzed the prognostic factors of high-grade mediastinal emphysema, including the presence or absence of PEECS.

RESULTS

The PEECS-positive group comprised 18 out of the 163 patients (11.0%), and mediastinal emphysema was stratified into grades 0 (94), 1 (51), 2 (12), 3 (5), and 4 (1 patient). Three independent risk factors for the onset of PEECS were identified, as follows: resected area ≥750 mm2 (OR 7.28, 95% CI 1.42-37.33, p = 0.017), treatment duration ≥75 min (OR 10.26, 95% CI 1.20-87.77, p = 0.034), and muscle layer exposure (OR 10.92, 95% CI 2.22-53.74, p = 0.003). Two independent predictive factors of high-grade mediastinal emphysema were identified, which were PEECS positivity (OR 4.31, 95% CI 1.29-14.41, p = 0.018), and muscle layer exposure (OR 4.08, 95% CI 1.18-14.06, p = 0.026).

CONCLUSIONS

A large resected area, prolonged treatment duration, and muscle layer exposure are risk factors for the onset of PEECS. Mediastinal emphysema was observed in 43% of patients following ESD. When marked clinical symptoms of PEECS appear, high-grade mediastinal emphysema may be observed, and therefore CT should be performed in these cases.

Neuroendocrine carcinoma of the common bile duct associated with congenital bile duct dilatation: a case report

Background

Cholangiocarcinoma is frequently observed in patients with congenital bile duct dilatation (CBDD). Most cholangiocarcinomas are adenocarcinomas. Other types, especially neuroendocrine carcinomas (NECs), are rare. To the best of our knowledge, this is the third reported case of an NEC of the common bile duct associated with CBDD and the first to receive adjuvant chemotherapy for advanced disease.

Case presentation

A 29-year-old woman presented with upper abdominal pain. Preoperative imaging indicated marked dilatation of the common bile duct and a tumor in the middle portion of the common bile duct. She was suspected of having distal cholangiocarcinoma associated with CBDD and underwent pylorus-preserving pancreaticoduodenectomy. Pathological and immunohistological findings led to a final diagnosis of large-cell NEC (pT3aN1M0 pStageIIB). The postoperative course was uneventful, and she was administered cisplatin and irinotecan every 4 weeks (four cycles) as adjuvant chemotherapy. She has remained recurrence-free for 16 months.

Conclusions

NEC might be a differential diagnosis in cases of cholangial tumor associated with congenital bile duct dilatation. This presentation is rare and valuable, and to establish better treatment for NEC, further reports are necessary.

Causative bacteria associated with a clinically relevant postoperative pancreatic fistula infection after distal pancreatectomy

PURPOSE

Clinically relevant postoperative pancreatic fistulas (CR-POPF) occurring after distal pancreatectomy often cause intra-abdominal infections. We monitored the presence of bacterial contamination in the ascitic fluid after distal pancreatectomy to clarify the bacterial origin of intra-abdominal infections associated with CR-POPF.

METHODS

In 176 patients who underwent distal pancreatectomy, ascitic fluid bacterial cultures were performed on postoperative days (POD) 1-4 and when the drainage fluid became turbid. The association between postoperative ascitic bacterial contamination and CR-POPF incidence was investigated.

RESULTS

CR-POPF occurred in 18 cases (10.2%). Among the patients with CR-POPF, bacterial contamination was detected in 0% on POD 1, in 38.9% on POD 4, and in 72.2% on the day (median, day 9.5) when the drainage fluid became turbid. A univariate analysis revealed a significant difference in ascitic bacterial contamination on POD 4 (p  < 0.001) and amylase level on POD 3-4 (p  < 0.001). A multivariate analysis revealed the amylase level and ascitic bacterial contamination on POD 4 to be independent risk factors.

CONCLUSIONS

In the CR-POPF group, ascitic bacterial contamination was not observed in the early postoperative stage, but the bacterial contamination rate increased after pancreatic juice leakage occurred. Therefore, CR-POPF-related infections in distal pancreatectomy may be caused by a retrograde infection of pancreatic juice.