Pancreatobiliary Maljunction-associated Gallbladder Cancer Is as Common in the West, Shows Distinct Clinicopathologic Characteristics and Offers an Invaluable Model for Anatomy-induced Reflux-associated Physio-chemical Carcinogenesis.

OBJECTIVE: To determine the associations of pancreatobiliary maljunction (PBM) in the West. BACKGROUND: PBM (anomalous union of common bile duct and pancreatic duct) is mostly regarded as an Asian-only disorder, with 200X risk of gallbladder cancer (GBc), attributed to reflux of pancreatic enzymes. Methods: Radiologic images of 840 patients in the US who underwent pancreatobiliary resections were reviewed for PBM and contrasted with 171 GBC cases from Japan. RESULTS: Eight % of the US GBCs (24/300) had PBM (similar to Japan; 15/ 171, 8.8%), in addition to 1/42 bile duct carcinomas and 5/33 choledochal cysts. None of the 30 PBM cases from the US had been diagnosed as PBM in the original work-up. PBM was not found in other pancreatobiliary disorders. Clinicopathologic features of the 39 PBM-associated GBCs (US:24, Japan:15) were similar; however, comparison with non-PBM GBCs revealed that they occurred predominantly in females (F/M = 3); at younger (<50-year-old) age (21% vs 6.5% in non-PBM GBCs; P = 0.01); were uncommonly associated with gallstones (14% vs 58%; P < 0.001); had higher rate of tumor-infiltrating lymphocytes (69% vs 44%; P = 0.04); arose more often through adenoma-carcinoma sequence (31% vs 12%; P = 0.02); and had a higher proportion of nonconventional carcinomas (21% vs 7%; P = 0.03). Conclusions: PBM accounts for 8% of GBCs also in the West but is typically undiagnosed. PBM-GBCs tend to manifest in younger age and often through adenoma-carcinoma sequence, leading to unusual carcinoma types. If PBM is encountered, cholecystectomy and surveillance of bile ducts is warranted. PBM-associated GBCs offer an invaluable model for variant anatomy-induced chemical (reflux-related) carcinogenesis.

Peripherally acting µ-opioid antagonist for the treatment of opioid-induced constipation: Systematic review and meta-analysis.

BACKGROUND AND AIM: Opioid-induced constipation (OIC) is a frequent adverse event (AE) that impairs patients' quality of life (QOL). Peripherally acting µ-opioid receptor antagonists (PAMORAs) have been recognized as a treatment option for OIC, but the effect consistent across the studies has not been evaluated. METHODS: We conducted a quantitative meta-analysis to explore the efficacy of PAMORA for OIC (registered with PROSPERO: CRD42018085298). We systematically searched randomized controlled trials (RCTs) in Medline, Embase, and Central databases. Change from baseline in spontaneous bowel movements, pooled proportion of responders, QOL, and AEs were calculated and compared with results in placebo cases. RESULTS: We included 31 RCTs with 7849 patients. A meta-analysis revealed that patients under PAMORA therapy had considerably improved spontaneous bowel movement from baseline compared with those given placebo (20 RCTs; mean difference, 1.43; 95% confidence interval [CI], 1.18-1.68; n = 5622) and more responded (21 RCTs; risk ratio [RR], 1.81; 95% CI, 1.55-2.12; n = 4821). Moreover, QOL of patients receiving PAMORA was significantly better (8 RCTs; mean difference, -0.22; 95% CI, -0.28 to -0.17; n = 2884). AEs were increased significantly in the PAMORA group (26 RCTs; RR, 1.10; 95% CI, 1.06-1.15; n = 7715), especially in gastrointestinal disorders, whereas serious AEs were not significant (17 RCTs; RR, 1.04; 95% CI, 0.85-1.28; n = 5890). CONCLUSION: Peripherally acting µ-opioid receptor antagonist has been shown to be effective and durable for patients with OIC and is the only drug with confirmed evidence in meta-analysis. The possibility of publication bias was the limitation of this study.

Reflux-Associated Cholecystopathy: Analysis of 76 Gallbladders From Patients With Supra-Oddi Union of the Pancreatic Duct and Common Bile Duct (Pancreatobiliary Maljunction) Elucidates a Specific Diagnostic Pattern of Mucosal Hyperplasia as a Prelude to Carcinoma.

Pancreaticobiliary maljunction (PBM) is the anomalous union of the main pancreatic duct and common bile duct outside the Oddi-sphincter, allowing the reflux of pancreatic juice to the gallbladder. There is only limited awareness and understanding of the pathologic correlates of this condition, mostly from Japan; this entity is largely unrecognized in the West. In this study, 76 gallbladders from patients with PBM (64 from Japan; 12 from the United States) were analyzed and contrasted with 66 from non-PBM patients. These were predominantly females (54 vs. 22), mean age, 53 (range: 14 to 81). Cholelithiasis was uncommon (16% vs. 80% in non-PBM, P<0.01) whereas cholesterolosis was more common (49% vs. 29%, P=0.02) suggesting an altered chemical milieu. There was a distinctive diffuse mucosal hyperplasia (82% vs. 42%, P<0.01) with markedly elongated folds (mean: 1.1 vs. 0.7 mm, P<0.01) composed of compact villoglandular proliferation, often showing broad-based pushing into muscle, accompanied by prominent and more complex Rokitansky-Aschoff sinus formation (2.0 vs. 1.0/cm, P<0.01) at the base. At the tips, this villiform hyperplasia displayed frequent horizontal bridging of the folds (68% vs. 47%, P=0.01), bulbous dilatation (52% vs. 21%, P<0.01) as well as deposition of a peculiar amyloid-like hyaline material (56% vs. 15%, P<0.01). Despite paucity of inflammation and gallstones, findings attributed to mucosal injury were common including: pyloric gland metaplasia (70% vs. 48%, P=0.01) and intestinal metaplasia (24% vs. 6%, P<0.01). Invasive gallbladder carcinoma was present in 22 (29%) of the cases with 6 of these (27%) arising in association with intracholecystic papillary tubular neoplasm. Five cases had bile duct carcinoma at the time of cholecystectomy and 1 developed it 4 years after. In conclusion, gallbladders with patients with PBM display a distinctive pattern of mucosal hyperplasia with distinguishing features, which in constellation render it a microscopically diagnosable specific entity. We propose to refer to this entity as "reflux-associated cholecystopathy." Recognition of the pathologic characteristics of this entity is important so that investigation for, as well as treatment and prevention of, PBM-associated complications (biliary tract cancers and pancreatitis) can be instituted. This group also offers a distinct model of carcinogenesis (chemical rather than inflammatory) in the gallbladder for cancer researchers to scrutinize.

Acute airway obstruction due to benign asymptomatic nodular goiter in the cervical region: A case report.

Benign nodular goiter is a common disease. Although large goiters with obstructive symptoms including shortness of breath and dyspnea are a clear indication for surgery, acute upper airway obstruction, particularly in benign cervical goiter cases, is rare. We herein report the case of 46-year-old female with acute upper airway obstruction due to benign nodular goiter. The patient had a large and elastic goiter which was more pronounced on the left side of her neck, and surgery was scheduled for within a few months. Three months after the initial presentation, while still waiting for surgery, the patient was brought to the emergency room due to loss of consciousness and breathing difficulty and was immediately intubated. A computed tomography (CT) scan revealed that the trachea was markedly compressed by a nodular lesion in the left lobe, and bilateral pneumonia was also evident. Total thyroidectomy was immediately performed via the supraclavicular approach. The patient had an uneventful postoperative course and recovered well. The resected specimen included a well-encapsulated solid and cystic mass. Histopathological examination mainly revealed adenomatous goiter. The present case suggests that benign asymptomatic nodular goiter mostly located in the neck may cause acute airway obstruction, even if the nodules are not large. Early surgery should be performed when tracheal deviation and stenosis due to a large goiter is prominent by CT scan.

Seminal vesicle-rectal fistula secondary to anastomotic leakage after low anterior resection for rectal cancer: a case report and brief literature review.

We report a case of a patient with seminal vesicle-rectal fistula, an extremely rare complication of low anterior resection of the rectum. A 53-year-old man with rectal adenocarcinoma underwent low anterior resection in our hospital. The patient experienced diarrhea, pneumaturia, and low-grade fever on postoperative day 13. A computed tomography scan showed emphysema in the right seminal vesicle. We concluded that anastomotic leakage induced a seminal vesicle-rectal fistula. The patient underwent conservative therapy with total parenteral nutrition and oral intake of metronidazole. Diarrhea and pneumaturia rapidly improved after metronidazole administration and the patient was successfully cured without invasive therapy such as colostomy or surgical drainage. A seminal vesicle-rectal fistula is a rare complication of low anterior resection, and therapeutic strategies for this condition remain elusive. Our report provides valuable information on the successful conservative treatment of a secondary seminal vesicle-rectal fistula that developed after low anterior resection of the rectum in a patient.

Humoral hypercalcemia associated with gastric carcinoma secreting parathyroid hormone: a case report and review of the literature.

Hypercalcemia with concomitant elevation of serum parathyroid hormone (PTH) and PTH-related protein (PTHrP) levels was found in a patient with advanced gastric carcinoma and multiple liver metastases. The most common features are hypercalcemia associated with hypersecretion of PTHrP and physiological suppression of PTH secretion in the syndrome of humoral hypercalcemia of malignancy (HHM). Although we initially made a diagnosis of primary hyperparathyroidism concomitant with HHM due to gastric cancer, diagnostic imaging studies, such as echography, CT, sestamibi scintigraphy, and autopsy findings, did not reveal evidence of any parathyroid tumors or ectopic parathyroid glands in the mediastinum. Both primary and metastatic tumor cells showed positive staining with PTH-specific antibody as well as PTHrP-specific antibody on immunohistochemical examination. PTH concentration in the cytosolic fraction of the metastatic tumor was elevated compared to that from a control patient with no calcium metabolic disorders in vitro. These findings indicated that PTH secreted ectopically by gastric cancer cells, not by parathyroid glands, caused hypercalcemia in this patient. To our knowledge, this is the first case report of PTH-secreting gastric carcinoma cells. We report the case and a review of the previous reported PTH-secreting non-parathyroid tumors along with the mechanisms of secretion.

Clinical characteristics of de novo nonalcoholic fatty liver disease following pancreaticoduodenectomy.

BACKGROUND: Hepatic steatosis may develop after pancreatic resection, but its clinicopathological features remain unclear. We explored the clinical characteristics of newly appearing nonalcoholic fatty liver disease (NAFLD) after pancreaticoduodenectomy (PD), designated as de novo NAFLD after PD. METHODS: Of 83 patients who underwent PD between 2001 and 2006, the patients with regular alcohol consumption after PD (n = 3), those who were unavailable for regular abdominal computed tomography follow-up (n = 12), and those who died within 6 months of PD (n = 8) were excluded from the study. In the remaining 60 patients, the prevalence and clinical features of de novo NAFLD after PD were examined. RESULTS: NAFLD developed after PD in 14 (23%) patients in our cohort. Liver biopsy was performed in 8 patients and all showed typical steatohepatitis. Compared with the patients who had conventional nonalcoholic steatohepatitis (NASH), patients with post-PD de novo NASH demonstrated significant decreases in body mass index and lower levels of serum albumin, cholesterol, apolipoprotein B, and homeostasis model assessment for insulin resistance. Multivariate logistic regression analysis revealed that pancreatic head cancer was associated with an increased risk of developing NAFLD after PD (odds ratio 12.0, 95% confidence interval 2.0-71.4, P = 0.006). Increased dosage of oral pancreatic enzymes significantly ameliorated the steatosis, as well as leading to the recovery of body weight loss and resolution of the biochemical abnormalities. CONCLUSIONS: De novo NAFLD/NASH after PD is characterized by non-obesity and lack of hyperlipidemia and insulin resistance and is associated with pancreatic exocrine insufficiency. In such patients, intensifying pancreatic enzyme supplementation may be useful.

Malignant tumor, of the gastrointestinal stromal tumor type, in the greater omentum.

We report herein a rare case of gastrointestinal stromal tumor (GIST) type, arising from the greater omentum. A 65-year-old man who had a large abdominal tumor was referred to our hospital. Ultrasonography (US) and computed tomography (CT) scans showed a mass occupying almost the entire abdomen anterior to the bowel loops. Abdominal angiography showed that the main feeding artery of the tumor was the right gastroepiploic artery. The preoperative diagnosis was suspected gastric leiomyosarcoma. Laparotomy revealed a large mass arising from the greater omentum, and the tumor seemed to be completely excised. Histopathological and immunohistochemical studies indicated the tumor had the same characteristics as GIST. Twelve months after the operation, the tumor recurred in the peritoneal cavity at the site of the stomach, and was associated with multiple liver metastases. The patient died of hypovolemic shock. Necropsy revealed that rupture of one of the metastatic liver tumors had resulted in a massive intraperitoneal hemorrhage.