須田 康一

Subtotal colectomy is often performed on patients with synchronous colorectal cancer. However, compared with colorectal anastomosis, ileorectal anastomosis with subtotal colectomy is more likely to result in bowel dysfunction. The Deloyers procedure is useful in preserving bowel function in a patient with synchronous colorectal cancer. An 87-year-old man presented with bloody stool. Colonoscopy showed masses in the cecum, transverse colon, rectosigmoid, and rectum above the peritoneal reflection. Computed tomography scan revealed no evidence of regional lymph node swelling and distant metastasis. Therefore, robot-assisted low anterior resection, laparoscopic extended left hemicolectomy, laparoscopic cecal resection, and diverting ileostomy were performed. The patient was discharged from the hospital without complications. There was no recurrence, and the patient did not have complaints such as urgency, fecal incontinence, and excretory dysfunction. Hence, minimally invasive coloproctectomy using the Deloyers procedure can be safe and useful in preserving postoperative bowel function in elderly patients.

BACKGROUND: Nonresectable gastric cancer develops rapidly; thus, monitoring disease progression especially in patients receiving nivolumab as late-line therapy is important. Biomarkers may facilitate the evaluation of nivolumab treatment response. Herein, we assessed the utility of serum-based inflammatory indicators for evaluating tumor response to nivolumab. METHODS: This multicenter retrospective cohort study included 111 patients treated with nivolumab monotherapy for nonresectable advanced or recurrent gastric cancer from October 2017 to October 2021. We measured changes in the C-reactive protein (CRP)-to-albumin ratio (CAR), platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte ratio (NLR) in serum from baseline to after the fourth administration of nivolumab. Furthermore, we calculated the area under the receiver operating characteristic curves (AUC ROCs) for CAR, PLR, and NLR to identify the optimal cutoff values for treatment response. We also investigated the relationship between clinicopathologic factors and disease control (complete response, partial response, and stable disease) using the chi-squared test. RESULTS: The overall response rate (complete and partial response) was 11.7%, and the disease control rate was 44.1%. The median overall survival (OS) was 14.0 (95% CI 10.7‒19.2) months, and the median progression-free survival (PFS) was 4.1 (95% CI 3.0‒5.9) months. The AUC ROCs for CAR, PLR, and NLR before nivolumab monotherapy for patients with progressive disease (PD) were 0.574 (95% CI, 0.461‒0.687), 0.528 (95% CI, 0.418‒0.637), and 0.511 (95% CI, 0.401‒0.620), respectively. The values for changes in CAR, PLR, and NLR were 0.766 (95% CI, 0.666‒0.865), 0.707 (95% CI, 0.607‒0.807), and 0.660 (95% CI 0.556‒0.765), respectively. The cutoff values for the treatment response were 3.0, 1.3, and 1.4 for CAR, PLR, and NLR, respectively. The PFS and OS were significantly longer when the treatment response values for changes in CAR, PLR, and NLR were below these cutoff values (CAR: OS, p < 0.0001 and PFS, p < 0.0001; PLR: OS, p = 0.0289 and PFS, p = 0.0302; and NLR: OS, p = 0.0077 and PFS, p = 0.0044). CONCLUSIONS: Measurement of the changes in CAR, PLR, and NLR could provide a simple, prompt, noninvasive method to evaluate response to nivolumab monotherapy. TRIAL REGISTRATION: This study is registered with number K2023006.

Abstract Background The advantages of robot‐assisted minimally invasive esophagectomy (RA‐MIE) over conventional minimally invasive esophagectomy (C‐MIE) are unknown. This nationwide large‐scale study aimed to compare surgical outcomes between RA‐MIE and C‐MIE using rigorous propensity score methods, including detailed covariates and relevant outcomes. Methods This Japanese nationwide retrospective cohort study included RA‐MIE or C‐MIE for esophageal malignant tumors performed between October 2018 and December 2019 and registered in the Japanese National Clinical Database. The primary outcome measure was postoperative complications classified as Clavien–Dindo Grade IIIa or higher. Propensity score matching was performed to create a balanced covariate distribution between the two groups. Results After propensity score matching, 1092 patients were selected. The RA‐MIE group had a significantly longer operation time and greater blood loss than the C‐MIE group (565 vs. 477 min and 120 vs. 90 mL). Furthermore, the R0 resection rate was lower in the RA‐MIE group than in the C‐MIE group (95.1% vs. 97.8%). The RA‐MIE and C‐MIE groups had no differences regarding overall complications ≥ Grade IIIa (22.0% vs. 20.3%, p = 0.52), 30‐day mortality rates (0.4% vs. 0.5%), and operative mortality rates (0.7% vs. 0.7%). Deep SSI was less frequent (2.7% vs. 6.0%) and pulmonary embolism was more frequent (2.4% vs. 0.5%) in the RA‐MIE group than in the C‐MIE group. Conclusions In the initial phase of implementation, RA‐MIE and C‐MIE demonstrated comparable morbidity rates when performed by skilled board‐certified endoscopic surgeons.

BACKGROUND: Adenosquamous carcinoma of the pancreas (ASCP) accounts for only 1-4% of all pancreatic exocrine cancers and has a particularly poor prognosis. The efficacy of chemotherapy for ASCP remains unknown because of the small number of cases, and few studies have evaluated conversion-intended chemotherapy. CASE PRESENTATION: A 76-year-old woman was referred to our hospital because of epigastric pain and nausea. A preoperative contrast-enhanced multidetector row computed tomography (MDCT) scan revealed a 17 × 17 mm low-density tumor with an ill-defined margin at the arterial phase in the pancreatic head. The tumor involved the common hepatic artery, left hepatic artery bifurcated from the common hepatic artery, and gastroduodenal artery, and was in contact with the portal vein. Fluorodeoxyglucose-positron emission tomography (FDG-PET) showed an uptake in the pancreatic head but no evidence of distant metastasis. The tumor was diagnosed as an adenocarcinoma of the pancreatic head and staged unresectable because the common and left hepatic arteries were involved. Hence, the patient underwent seven courses of conversion-intended chemotherapy using gemcitabine and nab-paclitaxel for pancreatic ductal adenocarcinoma over 7 months. After chemotherapy, the tumor shrank to 10 × 10 mm on contrast-enhanced MDCT. Consequently, the boundary between the tumor and major vessels of the common and left hepatic arteries and the portal vein became clear, and the involvement of the arteries with the tumor was evaluated to be released. The contact of the tumor to the portal vein also reduced to less than half the circumference of the portal vein. FDG-PET showed decreased accumulation in the tumor. Hence, the tumor was judged resectable, and pancreaticoduodenectomy was performed. The tumor and major blood vessels were easily dissected and R0 resection was achieved. The patient experienced no major complications and was discharged on postoperative day 28. The tumor was revealed as ASCP via pathological examination. The patient is alive and recurrence-free seven months after surgery. This is the first report of successful R0 resection for an initially unresectable ASCP following conversion-intended chemotherapy using gemcitabine and nab-paclitaxel regimen. CONCLUSIONS: Conversion-intended chemotherapy using gemcitabine and nab-paclitaxel regimen may be effective for ASCP.

BACKGROUND: This study aimed to investigate the laparoscopic gastrectomy (LG) performance of non-Endoscopic Surgical Skill Qualification System (ESSQS)-qualified surgeons under the ESSQS-qualified surgeon guidance and compare oncological outcomes of gastric cancer to LG performed by the ESSQS-qualified surgeons. METHODS: This study enrolled 1,030 patients diagnosed with both clinical and pathological stage ≤ III gastric cancer and undergoing LG from January 2009 to June 2019. ESSQS-qualified surgeons served as the operator or the instructive assistant in all LG procedures involving them. A propensity score-matched analysis was used to retrospectively compare the long-term outcomes between the ESSQS-qualified and non-ESSQS-qualified surgeons. RESULTS: Each group included 315 pairs after propensity score matching. The 3-year recurrence-free survival rates were 84.4% and 81.7% in the non-ESSQS and ESSQS groups, respectively. The difference was 2.7% (95% confidence interval: - 3.20%-8.44%, P < 0.001), and the non-ESSQS group statistically demonstrated noninferiority as the lower 95% confidence limit was greater than the prespecified margin of -10%, indicating the achieved primary endpoint. No significant differences in 5-year recurrence-free survival (non-ESSQS: 78.5% vs. ESSQS: 77.4%, P = 0.627) and 5-year overall survival (non-ESSQS: 80.9% vs. ESSQS: 79.3%, P = 0.475) were found between the two groups. The oncological outcomes stratified according to the presence of pathological stage I, II, and III disease did not significantly differ between the two groups. CONCLUSIONS: LG performed by non-ESSQS-qualified surgeons achieved comparable oncological outcomes to the ESSQS-qualified surgeons, as long as ESSQS-qualified surgeons provided intraoperative instructions, in a high-volume center.