Long-term outcomes and survival analysis of cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy in patients with pseudomyxoma peritonei at a newly established peritoneal malignancy centre in Japan.

Background: Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is established in the management of pseudomyxoma peritonei (PMP), selected cases of peritoneal mesothelioma, and resectable colorectal or ovarian peritoneal metastases in Western countries. However, the efficacy and feasibility of these techniques are not well established in the Asian population, and little has been reported on long-term survival outcomes for surgically resected PMP patients. Materials and Methods: Retrospective analysis of a prospective database of short- and longer-term outcomes of consecutive patients who underwent CRS and HIPEC for PMP in a newly established peritoneal malignancy unit in Japan between 2010 and 2016. Results: A total of 105 patients underwent CRS and HIPEC and 57 maximal tumor debulking (MTD) for pseudomyxoma peritonei. In the CRS group, the primary tumor was appendiceal in 94 patients (90%) followed by ovarian and colorectal. Major postoperative complications occurred in 22/105 patients (21%) with one in-hospital mortality (0.9%). The 5-year overall and disease-free survival rates for the CRS group were 74.2% and 50.1%, respectively. Multivariate analysis revealed unfavorable histology to be the significant predictor of reduced overall and disease-free survival. Completeness of cytoreduction, CA19-9, and CA125 were also associated with disease-free survival. Conclusions: This is the first report on long-term outcomes and survival analysis of CRS and HIPEC for PMP in the Asian population. CRS and HIPEC can be conducted with reasonable safety and favorable survival in a new center. Complete tumor removal and histological type are the strongest prognostic factors for both overall and disease-free survival.

Non-operative management involving chemoradiation therapy combined with high-dose-rate brachytherapy for T3 rectal cancer using a vaginal shielded cylindrical applicator: a technical report.

It has been shown that a group of rectal cancer patients will achieve a pathological complete response following preoperative chemoradiotherapy, and non-operative management has recently gained attention. To escalate the tumour dose and increase the likelihood of pathological complete response, brachytherapy can play an important role in safely increasing the total dose. However, at the time this report was published, an applicator dedicated to rectal brachytherapy was unaffordable in Japan. Here, we report two T3 rectal cancer patients who were inoperable or refused surgery and treated by chemoradiotherapy following intracavitary brachytherapy involving a vaginal cylinder applicator with lead shielding.

Prediction of mismatch repair deficient biliary tract cancer: Role of morphological features and host immune response detected by routine hematoxylin-eosin staining.

BACKGROUND/PURPOSE: The objective of this study was to determine the frequency and predictors of biliary tract cancer (BTC) with deficient DNA mismatch repair (dMMR) in Japan. METHODS: Immunostaining and microsatellite instability analysis were performed for mismatch repair-related proteins in tissue specimens from 662 patients who underwent surgery for BTC between 2001 and 2017 to identify dMMR-BTC. We compared dMMR-BTC and proficient MMR (pMMR)-BTC based on patient demographics, pathological features, and host immune responses characterized by the percentage of stromal tumor infiltrating lymphocytes (sTIL percentage) and tertiary lymphoid structures (TLS). RESULTS: The incidence of dMMR-BTC was 2.3%. Significant predictors of dMMR-BTC were its primary lesion being intrahepatic cholangiocarcinoma (odds ratio [OR] 6.34, P = .004), presence of signet ring cell component (OR 35.62, P < .001), sTIL percentage ≥40% (OR 3.43, P = .038), and presence of TLS (OR 22.22, P < .001). The sensitivity, specificity, and negative likelihood ratio for any one or more of these four variables to be positive were 93.3%, 57.8%, and 0.12, respectively. CONCLUSION: Evaluation of histopathological findings and host immune response based on conventional histochemical staining is useful for efficient and inexpensive diagnostic screening of dMMR-BTC patients.

[A Case of Jejunal Ectopic Pancreatic Cancer with Small Bowel Obstruction].

Were port a caseof an 82-year-old man who presented with vomiting. Computed tomography(CT)revealed a jejunum tumor and small bowel obstruction. Enteroscopy revealed a protruded lesion and biopsy indicated adenocarcinoma. PET-CT revealed nothing without jejunal tumor. Therefore, with a preoperative diagnosis of primary small bowel cancer, we performed operation. Surgery indicated peritoneal disseminations and a jejunal tumor 40 cm distal from the ligament of Treitz, and we performed small bowel partial resection. Pathological examination revealed adenocarcinoma originating from a Heinrich type I ectopic pancreas in the jejunum. Ectopic pancreatic cancer in the jejunum is rare, and we review case reports in the literature.

A case of ileocecal actinomycosis treated by preoperative antibiotic treatment to reduce mass size followed by surgical resection.

A 65-year-old woman presented to a nearby clinic with a painful mass in the right lower abdominal region. She was suspected of having an appendiceal tumor on abdominal computed tomography (CT) and was referred to our hospital for surgery. Blood testing revealed increased inflammatory markers. Contrast-enhanced abdominal CT revealed a mass with poorly defined margins in the ileocecal region, which was adjacent to the external iliac vessels. A barium enema revealed unilateral wall deformities in the cecum through to the terminal ileum, whereas lower gastrointestinal endoscopy showed no clear epithelial tumor component. The patient was clinically diagnosed with ileocecal actinomycosis and treated with high-dose penicillin G. On day 15 of treatment, contrast-enhanced abdominal CT showed a reduction in mass size. On day 26, right hemicolectomy (D3) with combined resection of the external iliac vein (which could not be separated from the mass) was performed. Pathological examination revealed granulation tissue with granules of actinomyces, with filamentous bacteria detected by Grocott staining. With no evidence of malignancy, the final diagnosis of ileocecal actinomycosis was made. This report presents a case of clinically suspected ileocecal actinomycosis treated by preoperative antibiotic treatment to reduce mass size, followed by surgical resection.

Molecular profiles of high-grade and low-grade pseudomyxoma peritonei.

Pseudomyxoma peritonei (PMP) is a rare disease exhibiting a distinct clinical feature caused by cancerous cells that produce mucinous fluid in the abdominal cavity. PMPs originate most frequently from the appendix and less frequently from the ovary. This disease can range from benign to malignant, and histologically, PMP is classified into two types: disseminated peritoneal adenomucinosis (DPAM) representing the milder phenotype, and peritoneal mucinous adenocarcinomas (PMCA) representing the aggressive phenotype. Although histological classification is clinically useful, the pathogenesis of PMP remains largely unknown. To elucidate the molecular mechanisms underlying PMP, we analyzed 18 PMP tumors comprising 10 DPAMs and 8 PMCAs. DNA was extracted from tumor and matched non-tumorous tissues, and was sequenced using Ion AmpliSeq Cancer Panel containing 50 cancer-related genes. Analysis of the data identified a total of 35 somatic mutations in 10 genes, and all mutations were judged as pathological mutations. Mutations were frequently identified in KRAS (14/18) and GNAS (8/18). Interestingly, TP53 mutations were found in three of the eight PMCAs, but not in the DPAMs. PIK3CA and AKT1 mutations were also identified in two PMCAs, but not in the DPAMs. These results suggested that KRAS and/or GNAS mutations are common genetic features of PMP, and that mutations in TP53 and/or genes related to the PI3K-AKT pathway may render malignant properties to PMP. These findings may be useful for the understanding of tumor characteristics, and facilitate the development of therapeutic strategies.

Acinar cell carcinoma of the pancreas with colon involvement.

We report a case of acinar cell carcinoma of the pancreas with colon involvement that was difficult to distinguish from primary colon cancer. A 60-year-old man was admitted with a 1-month history of diarrhea. Contrast-enhanced computed tomography (CT) revealed a large tumor (10.6 × 11.6 cm) at the splenic flexure of the colon. Colonoscopy showed completely round ulcerative lesions, and biopsy revealed poorly differentiated adenocarcinoma. Left hemicolectomy, resection of the jejunum and pancreas body and tail, and splenectomy were performed based on a diagnosis of descending colon cancer (cT4N0M0, stage IIB), and surgery was considered to be curative. Diagnosis was subsequently confirmed as moderately differentiated acinar cell carcinoma of the pancreas by immunohistochemical staining (pT3N0M0, stage IIA). Multiple liver metastases with portal thrombosis were found 8 weeks postoperatively. Despite combination chemotherapy with oral S-1 and gemcitabine, the patient died of hepatic failure with no effect of chemotherapy 14 weeks postoperatively. Correct diagnosis was difficult to determine preoperatively from the clinical, CT, and colonoscopy findings. Moreover, the disease was extremely aggressive even after curative resection. Physicians should consider pancreatic cancer in the differential diagnosis of similar cases.

Increase in colonic diverticulosis and diverticular hemorrhage in an aging society: lessons from a 9-year colonoscopic study of 28,192 patients in Japan.

PURPOSES: Colonoscopic evidence of epidemiological trends in diverticulosis and diverticular bleeding is scarce. We evaluated trends in diverticular disease and associated factors over 9 years. METHODS: Twenty-eight thousand one hundred ninety-two patients who underwent colonoscopy at an emergency hospital were reviewed from an electronic endoscopy database. Diverticula were classified as right-sided, left-sided, and bilateral types, and time trends in the proportion in diverticulosis, type, and diverticular bleeding were determined. Associations of age (≤39, 40-59, and ≥60 years), sex, and year increase with disease and odds ratios were estimated using logistic regression. RESULTS: Diverticulosis was identified in 6,150 patients (20.3 %; mean age, 67.6 years) and was predominantly right-sided (48.0 %). Diverticular bleeding was found in 427 (1.5 %; mean age, 69.7 years) and was predominantly bilateral (47.0 %). Proportion of colonic diverticulosis increased significantly (P < 0.01 for trend) from 66.0 % (1,424/2,157) in 2003 to 70.1 % (2,914/4,159) in 2011 and was associated (P < 0.01) with an increased number of patients aged ≥60 years. Proportion of diverticular bleeding increased significantly (P < 0.01 for trend) from 1.02 % (22/2,157) in 2003 to 1.67 % (69/4,159) in 2011 and was associated (P = 0.04) with an increased number of patients aged 40-59 years. Diverticulosis, right and bilateral type, and diverticular bleeding were independently associated with the 9-year trend after adjustment by age and sex. CONCLUSIONS: Colonic diverticulosis and diverticular bleeding are prevalent and increasing in Japan. Given the significant association of age with this trend, both diseases can be expected to increase for decades to come.

Impact of non-congestive graft size in living donor liver transplantation: new indicator for additional vein reconstruction in right liver graft.

Addition of the middle hepatic vein (MHV) or reconstruction of its tributaries to increase noncongestive graft volume is expected to improve graft function in right liver living donor liver transplantation (LDLT). However, the relationship between noncongestive graft volume and graft function after transplantation has not been clarified and definitive criteria for the reconstruction of MHV tributaries have yet to be established. We analyzed 29 right liver LDLT cases. The noncongestive graft weight was calculated as the total weight of the graft regions drained by hepatic veins reconstructed without postoperative occlusion. We calculated the noncongestive graft-to-recipient weight ratio (ncGRWR) by comparing it to the GRWR. Indocyanine green (ICG) clearance results on days 1 and 3 were significantly correlated with ncGRWR, but not with GRWR. Patients were then divided into 2 groups based on ncGRWR: lower than the median (L-ncGRWR group) and above the median (H-ncGRWR group). ICG clearance in the H-ncGRWR group was significantly better on days 1 and 3. For a different analysis, the patients were again divided into 2 groups, those with and without prolonged cholestasis after transplantation. ncGRWR was significantly lower in patients with prolonged cholestasis, and 7 of 9 patients with an ncGRWR value lower than 0.65 suffered from prolonged cholestasis. Our results demonstrated that the noncongestive volume of a right liver graft has a significant association with early graft function. Further, ncGRWR can play a key role in preoperative determination for additional vein reconstruction of MHV tributaries. When the estimated ncGRWR value with reconstruction of only the right hepatic vein (RHV) (+ inferior right hepatic vein [IRHV]) is less than 0.65, additional vein reconstruction of MHV tributaries should be planned.