No abstract

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.

To evaluate the potential of dextran-coated magnetite (DM) particles in enhancing the detection of hepatocellular carcinoma with magnetic resonance (MR) imaging, the authors induced liver tumors in rats by oral administration of diethylnitrosamine and examined the rats before and after intravenous injections of DM with various iron concentrations. Because of the intense and preferential T2 relaxativity of DM, use of DM with an iron concentration of 10 mumol/kg yielded effective MR signal reduction in each normal liver at 1 hour after the injection. Because no significant signal change in the tumors was observed on DM-enhanced MR images, the contrast between hepatocellular carcinoma and adjacent uninvolved liver increased remarkably on even relatively T1-weighted images. The detection rate for the 89 tumors, including small tumors less than 2 mm in diameter, increased from 10% (nine of 89) before DM administration to 65% (58 of 89) with DM-enhanced T1-weighted imaging. Iron staining of rat liver performed about 1 hour after DM administration showed sparse deposits of DM selectively in reticuloendothelial cells but not in liver tumors.

Although reports on primary squamous cell carcinoma of the breast have been increasing in number, the morbidity rate of the disease is comparatively low. Its onset in pregnant women, especially, is quite rare. We herein report a case of primary squamous cell carcinoma of the breast in a pregnant woman. A 33-year-old woman was admitted with a lump in the right breast and an abnormal bloody nipple discharge. The breast mass was 5.6 x 5.4 cm in size, and both ultrasonogram and CT scanning showed that it consisted of a cystic tumor for the most part. A large amount of bloody cystic fluid was aspirated by fine-needle aspiration; squamous cell carcinoma of the breast was suspected by a cytological study on the fluid. Twelve days after an induced abortion was performed, a modified radical mastectomy was carried out. Histological findings of the resected specimen demonstrated that the tumor was squamous cell carcinoma which had been well differentiated with partial keratinization and cancer pearls. Noninvasive ductal carcinoma was also observed in a very small region of the specimen, which indicated that the tumor was probably originally adenocarcinoma which later transformed into squamous cell carcinoma.