Naoto Horigome

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.

Gas-forming liver abscess after transcatheter arterial embolization for hepatocellular carcinoma: Report of a case

A case of a gas-forming liver abscess developing after transcatheter arterial embolization for recurrent hepatocellular carcinoma (HCC) in a 65-year-old man is presented herein. He was admitted to hospital with fever and jaundice, following which ultrasonography (US) and computed tomography revealed a gas-containing abscess in the posterior segment of the hepatic lobe with multiple HCC. Percutaneous transhepatic drainage was performed using US. Antibiotics which were sensitive to theEscherichia coli bacteria detected in the abscess were administered both intravenously and through the drainage tube into the abscess. Four months later, the abscess had diminished and the patient was discharged after receiving percutaneous ultrasonographically guided ethanol injection therapy for the recurrent HCC.

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.

The antitumor activity and immunosuppressive effects of 5-fluorouracil suppositories in rectal cancer patients

The antitumor activity and immunological effects of the local administration of 5FU were investigated by determining the tissue concentration of 5FU, histological appearance of the primary tumor, and lymphocyte subsets of the regional lymph nodes in 23 rectal cancer patients. Twelve patients were treated with 5FU suppositories preoperatively, being the 5FU group, while 11 patients were given no preoperative treatment, being the control group. The 5FU concentrations in the primary tumors were higher than those in the regional lymph nodes and appeared to remain high for an extended period. No histological changes peculiar to the 5FU group were observed in the primary tumors. An analysis of the lymphocyte subsets in the pararectal nodes revealed that Leu2a+15− cells, or cytotoxic T lymphocytes, were significantly decreased in numbers in the 5FU group compared to the control group. These results suggest that the local use of 5FU may not only exert an antitumor effect against rectal cancer, but can also cause the suppression of antitumor immunity in the regional lymph nodes.

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.