Robotic surgery is increasingly adopted for rectal cancer management, including selected patients with locally advanced disease. We evaluated perioperative safety and medium- to long-term outcomes after robot-assisted rectal cancer surgery with multivisceral resection for cT4 rectal cancer in a single high-volume center. We retrospectively reviewed 45 consecutive patients with locally advanced rectal cancer who underwent robot-assisted surgery with multivisceral resection between April 2021 and June 2025. Demographic and clinical variables, surgical and postoperative outcomes, and pathological findings were extracted from medical records. Recurrence-free survival (RFS), overall survival, and local recurrence were assessed. The study included 45 patients (19 females) with a median age of 72 years. Postoperative complications of Clavien–Dindo grade III or higher occurred in 4 patients (8.8

INTRODUCTION:Factor XIII deficiency (FXIIID) is a rare coagulation disorder that can cause severe or delayed bleeding and impair wound healing despite normal routine coagulation test results. Congenital FXIIID is caused by homozygous germline pathogenic variants of F13A or F13B. Herein, we report the successful treatment of a patient with FXIIID who underwent surgery for juvenile polyposis syndrome (JPS)-associated early gastric cancer. CASE PRESENTATION:A 44-year-old woman was admitted to the hospital with anemia secondary to menorrhagia. Gastrointestinal examination revealed polyposis throughout the stomach and type 0-Is early gastric cancer, which was consistent with the histological diagnosis of the biopsy specimens. Investigation into her family history revealed that her mother and maternal aunt had gastric polyposis. Preoperative laboratory tests were almost normal, except for low levels of hemoglobin (6.0 g/dL) and Factor XIII (FXIII) activity (31%). Robot-assisted total gastrectomy with D1-level lymph node dissection, followed by Roux-en-Y reconstruction, was successfully performed, with an operative time of 347 min and estimated blood loss of 26 mL. To prevent surgery-related bleeding, preoperative and postoperative administration of FXIII concentrate (30 IU/kg) was planned. The postoperative course was uneventful, and the patient was discharged on POD 9. Genetic testing identified a germline pathogenic frameshift variant in SMAD4 (c.96delT [p.Ser32fs*13]), which was consistent with the phenotype of JPS, and a heterozygous missense variant of uncertain significance in F13A1 (c.308A>T [p.Glu103Val]). Nine months postoperatively, FXIII activity was re-evaluated and remained low at 59%, although it was higher than the preoperative level. CONCLUSIONS:Recognition of FXIIID and appropriate perioperative management may help prevent unexpected bleeding and enable safe gastrectomy in patients with FXIIID.

An 81-year-old woman visited our hospital for severe anemia and was diagnosed with ascending colon cancer with a tumor thrombus in the superior mesenteric vein(SMV). After 8 courses of mFOLFOX6+bevacizumab therapy followed by 7 courses of fluorouracil and leucovorin+bevacizumab therapy, the primary lesion and tumor thrombus were found to be shrinkage. Then we performed robot-assisted right hemicolectomy and resection of SMV involving the tumor thrombus. The patient was discharged on postoperative day 19. Histological findings revealed residual tumor thrombus in the SMV. The patient is currently under observation at 4 months postoperatively without adjuvant chemotherapy.

Pancreaticoduodenectomy(PD)has been increasingly performed as conversion surgery for advanced gastric cancer. We report 6 cases of gastric cancer in which PD was performed following chemotherapy. The reasons for requiring PD were pancreatic head invasion in 3 cases, common bile duct invasion in 1 case, and lymph node recurrence in the hepatic hilum after distal gastrectomy in 2 cases. Preoperative chemotherapy regimens included S-1+oxaliplatin in 3 cases, S-1+oxaliplatin+ trastuzumab in 1 case, capecitabine+oxaliplatin in 1 case, and S-1+cisplatin in 1 case. One patient died during hospitalization due to sepsis caused by postoperative cholangitis. A pancreatic fistula classified as Clavien-Dindo classification Grade Ⅲa occurred in 1 case. The 1-year and 2-year overall survival rates were 83.3% and 66.7%, respectively. The 1-year and 2- year recurrence-free survival rates were both 75.0%. Although the number of cases is limited, PD as conversion surgery for gastric cancer is considered an effective treatment option.

Intraoperative nerve monitoring (IONM) during esophageal cancer surgery can help to identify and preserve the recurrent laryngeal nerve (RLN). To devise a useful parameter for prediction of left vocal cord palsy (VCP), we measured the electromyographic (EMG) amplitude of the left RLN and vagus nerve (VN) using intermittent IONM. We studied 35 consecutive patients who underwent esophagectomy with lymph node dissection around the left RLN. After lymph node dissection, the left RLN and left VN were stimulated, and the EMG amplitude was measured using IONM. The VN/RLN ratio (V/R ratio) was calculated, and the presence of left VCP, diagnosed by laryngoscopy on the first postoperative day, was compared among the patients. Ten of the 35 patients (28.6

Between January 2020 and November 2024, we retrospectively analyzed the results of mismatch repair protein immunohistochemistry(MMR-IHC)/microsatellite instability(MSI)test, RAS, and BRAF genetic tests in 48 consecutive patients under 50 years of age who underwent primary tumor resection of colorectal cancer. Of these, 35 patients underwent MMR-IHC/ MSI testing, revealing 32 proficient MMR(pMMR)/non-MSI-high and 3 deficient MMR(dMMR)/MSI-high, 2 of whom were diagnosed as having Lynch syndrome. RAS/BRAF testing was performed in 28 patients, identifying 6 with KRAS variants, while no BRAFV600E or KRASG12C were found. The frequencies of dMMR and Lynch syndrome in patients under 50 years old was comparable to our previous report in which testing was conducted as part of research. Our results suggest that in patients under 50 years old(, 1)the utility of BRAF testing as an adjunctive diagnostic tool for Lynch syndrome is limited, and (2)BRAFV600E or KRASG12C was not detected;however, a larger accumulation of cases is necessary.

PURPOSE:This retrospective study was performed to investigate the recent trend of occurrence of cancer of the remnant colorectal segment(RCRS)after ileal-pouch anal anastomosis(IPAA)/ileorectal anastomosis(IRA)and to consider the optimal surveillance methods in patients with familial adenomatous polyposis(FAP)undergoing(procto)colectomy.PATIENTS AND METHODS:The subject was a total of patients with FAP undergoing IPAA or IRA between 2005 and 2022. Clinicopathological data were extracted from medical charts and analyzed. Cumulative incidence of cancer in the RCRS and overall survival after treatment of such tumors were calculated by the Kaplan-Meier method.RESULTS:There were 45 male and 56 female. IPAA was performed in 49 patients(hand-sewn; n=33, stapled; n=16)and IRA was performed in 52 patients. The median age at initial colorectal surgery was 32 years old(range, 13-66 years old). Median postoperative follow-up was 11 years(range, 1-48 years). Eighty-one patients were confirmed to have pathogenic variant of APC by genetic test. The cumulative incidence of cancer of the RCRS did not differ between patients undergoing IPAA and those undergoing IRA(p= 0.73, 4.1% versus 1.9% at 10 years). The cumulative 5-year overall survival rate after additional surgery for the tumor of RCRS was 82%.CONCLUSION:This study has several limitations due to single institutional retrospective study with small cases and non-standardized postoperative endoscopic surveillance. However, our results seem to show satisfactory oncological outcomes of patients with FAP in terms of the control of cancer of the RCRS under postoperative periodic surveillance, regardless of the type of colorectal resection.

Cronkhite-Canada syndrome(CCS)is a rare non-inherited disease characterized by gastrointestinal polyposis and ectodermal abnormalities. We report a rare case of CCS associated with gastric cancer and gastric outlet obstruction with a review of the literature. A 75-year-old man was admitted because of frequent vomiting and hypoproteinemia. He was diagnosed with CCS due to typical clinical and laboratory findings including alopecia, nail atrophy, hypoproteinemia, and typical gastrointestinal polyposis. Upper endoscopic examination also pointed out a large gastric cancer mainly located in the antrum and the reversible pyloric obstruction caused by the gastric tumor. Biopsy of the tumor revealed tubular adenocarcinoma. Computed tomography demonstrated the dilated duodenum caused by packing of the gastric tumor. 1.5 months after prednisolone therapy, he underwent total gastrectomy with complete resection of the dilated duodenal bulb. Histological examination revealed gastric cancer(pap>tub1)classified into Stage ⅢC. Postoperative course was uneventful and he moved to another hospital. To our knowledge, including the present case, there were 20 reported cases of CCS associated with gastric cancer from Japan(1979-2022). Also, 7 cases of CCS associated with gastric outlet obstruction was reported.

Immune checkpoint inhibitors(ICIs)are widely used for the treatment of unresectable gastric cancer. We treated approximately 70 patients with ICIs. ICI treatment with pembrolizumab was administered for MSI-high cases and nivolumab for MSS cases in the second- or third-line chemotherapy. We observed 5 cases of complete response. Among these, 2 patients presented with liver metastases, 2 with peritoneal disseminations, and 1 with pulmonary metastasis. In 1 patient, the primary tumor invaded the diaphragm and descending aorta; whereas, in another patient the primary tumor invaded the pancreas and liver. All patients had progressive disease after first-line chemotherapy.

A 55-year-old woman had been admitted to a hospital with abdominal bloating. Retroperitoneal liposarcoma was suspected and diagnosed as not resectable. She was then referred to our hospital with dyspnea and difficulties with movement due to the huge mass. An abdominal CT revealed a large mass originating in the left retroperitoneum. The tumor occupied most of the abdominal cavity, resulting in the displacement of her organs. However, there was no evidence of infiltration of the tumor into the aorta and inferior vena cava. Under a provisional diagnosis of retroperitoneal liposarcoma, a surgical resection was undertaken. The resected specimen had a maximum diameter of 48 cm and weighed 14 kg. Histopathological examination revealed a differentiated liposarcoma. The patient remains alive 6 months after the operation, without recurrence.

Endocytoscopy (EC) facilitates real-time histological diagnosis of esophageal lesions in vivo. We developed a deep-learning artificial intelligence (AI) system for analysis of EC images and compared its diagnostic ability with that of an expert pathologist and nonexpert endoscopists. Our new AI was based on a vision transformer model (DeiT) and trained using 7983 EC images of the esophagus (2368 malignant and 5615 nonmalignant). The AI evaluated 114 randomly arranged EC pictures (33 ESCC and 81 nonmalignant lesions) from 38 consecutive cases. An expert pathologist and two nonexpert endoscopists also analyzed the same image set according to the modified type classification (adding four EC features of nonmalignant lesions to our previous classification). The area under the curve calculated from the receiver-operating characteristic curve for the AI analysis was 0.92. In per-image analysis, the overall accuracy of the AI, pathologist, and two endoscopists was 91.2%, 91.2%, 85.9%, and 83.3%, respectively. The kappa value between the pathologist and the AI, and between the two endoscopists and the AI showed moderate concordance; that between the pathologist and the two endoscopists showed poor concordance. In per-patient analysis, the overall accuracy of the AI, pathologist, and two endoscopists was 94.7%, 92.1%, 86.8%, and 89.5%, respectively. The modified type classification aided high overall diagnostic accuracy by the pathologist and nonexpert endoscopists. The diagnostic ability of the AI was equal or superior to that of the experienced pathologist. AI is expected to support endoscopists in diagnosing esophageal lesions based on EC images.

An 81-year-old female visited a local hospital with complaints of anal pain. A tumor was found on the right side of her anus, and the histopathological diagnosis was a non-epithelial malignant tumor. Therefore, the patient was referred to our hospital. Result of imaging inspection revealed that the tumor had invaded the lower rectum, but had not distantly metastasized. Based on the findings of another biopsy, the patient was diagnosed with a malignant peripheral nerve sheath tumor (MPNST). Robot-assisted abdominoperineal resection(D1)was performed, and the lesion was resected without any pathological remnants. During the postoperative period, the patient developed perineal wound infection. Subsequently, the patient was discharged from the hospital on postoperative day 10. At the 6-month postoperative follow-up, no recurrence was noted. Most MPNSTs occur in the limbs, trunk, and neck. MPNST in the primary gastrointestinal tract or in the vicinity of the gastrointestinal tract is relatively rare, and in principle, combined resection of the intestinal tract is required for surgical treatment. Here, we report a case of MPNST that occurred near the anus and infiltrated to the lower rectum and was completely resected by robot-assisted abdominoperineal resection.

Esophageal neuroendocrine carcinoma is extremely rare, and its treatment strategy has not been established. We report 2 cases esophageal neuroendocrine carcinoma. Case 1: A 74-year-old man was diagnosed as having esophageal neuroendocrine carcinoma(clinical T3N4M0, Stage Ⅳa). He received 60 Gy of radiation therapy with etoposide(100 mg/m2)plus cisplatin(80 mg/m2). No recurrence has been detected 1 year after treatment. Case 2: A 78-year-old man was diagnosed as esophageal neuroendocrine carcinoma(clinical T3N0M0, Stage Ⅱ). He underwent esophagectomy with 3 field lymph nodes dissection. Adjuvant chemotherapy was administered with irinotecan(60 mg/m2)plus cisplatin(60 mg/m2). After chemotherapy, he survived 1 year without recurrence.

We herein report 3 cases of advanced gastric cancer with multiple liver metastases who was successfully treated with systemic chemotherapy and underwent conversion surgery with liver resection. There were 2 males and 1 female patients with a range 68 to 74 years of age. Two patients received S-1 plus oxaliplatin therapy and 1 received S-1 plus cisplatin therapy. All patients survived after 5-49 months postoperatively.

We retrospectively analyzed clinicopathological and survival data of 8 patients with unresectable gastric cancer who underwent conversion surgery(CS)following second-line chemotherapy from April 2013 to December 2020. There were 7 males and 1 female patients with a median age of 69(64-76)years old. Five patients had 1 unresectable factor, 2 had 2 unresectable factors, and 1 had 3 unresectable factors. All patients achieved R0 resection. The median survival time(MST) of patients with CS following second-line chemotherapy was significantly longer than that without CS(73.4 vs 12.3 months, respectively). The MST of patients with CS following first-line chemotherapy was significantly longer than that without CS (22.9 vs 12.3 months, respectively). This study suggested that CS following first- or second-line chemotherapy may improve survival duration for unresectable gastric cancer.

The efficacy of pembrolizumab has been demonstrated for all solid tumors showing high frequency microsatellite instability- high(MSI-High). It is a possible treatment option even in cases which do not respond to other forms of chemotherapy. We report a case of a 69-year-old man with MSI-High recurrent colorectal cancer with complete response(CR)after pembrolizumab therapy. Sigmoidectomy, extensive lymph node dissection, and partial bladder resection were performed for sigmoid colon cancer at another hospital. Histopathological examination revealed a T4a, N0, M0, Stage Ⅱb tumor. Six months after the operation, Hartmann's operation and partial resection of the small intestine were performed for local recurrence. However, the tumor invading the retroperitoneum was unresectable. Postoperative SOX therapy was performed, but it was discontinued due to Grade 3 diarrhea during the first course. The laboratory test showed MSI-High during the first course. Pembrolizumab chemotherapy was introduced as second-line therapy. Computed tomography examination after 2 courses (6 weeks)revealed reduction in the major axis of the tumor by 30% or more. After 4 courses(12 weeks), the tumor was further reduced, and a partial response(PR)was diagnosed. The tumor completely disappeared after 6 courses, and a complete response was achieved after 8 courses. The CR has been maintained for about 7 months.

We experienced a case of low-grade appendiceal mucinous neoplasm complicated by pseudomyxoma peritonei that was successfully treated with cytoreductive surgery and early postoperative intraperitoneal chemotherapy. The patient was a 26- year-old man with massive ascites and a swollen appendix on the computed tomography(CT). The appendix was a cystic mass of 5 cm in size. The entire parietal peritoneum, omentum, stomach, spleen, gall bladder, and entire colon were covered with numerous mucous nodules. Total colectomy, total gastrectomy, splenectomy, cholecystectomy, total omentectomy, parietal peritonectomy, ileostomy, and intraperitoneal irrigation were performed. The pathological diagnosis was low-grade appendiceal mucinous neoplasm. Postoperative intraperitoneal chemotherapy with cisplatin and mitomycin C was performed. A residual tumor was found on the dorsal side of the hepatoduodenal ligament 3 months postoperation on the CT. The residual tumor was successfully excised via a concomitant resection of the hepatic caudate lobe. Postoperative intraperitoneal chemotherapy was then performed. No recurrence was found at 8 months postoperation. The addition of early postoperative intraperitoneal chemotherapy improved the patient's quality of life in a short period. This could be one of the treatment options.