Vinik Ai

Microgastrinomas of the duodenum: a cause of failed operations for the Zollinger-Ellison syndrome

Gastrinomas are now being detected at an earlier stage than was formerly the case. Furthermore, with the ability to control acid secretion, emphasis has been placed on identifying gastrinoma patients who are potentially curable by tumor resection rather than by palliative gastrectomy. Despites estimates suggesting that 20-40% of sporadic gastrinoma patients can be successfully resected for cure, as many as 40% of such patients have occult tumors that elude detection. In an effort to better localize gastrinomas, we have used percutaneous transhepatic venous (THVS) gastrin sampling over the past 10 years. From 1978 to 1988, THVS was used in 46 patients in whom there was no other evidence of metastatic gastrinoma by conventional studies. Gastrinomas were found at operation in all but one patient. The purpose of this report is to emphasize that occult tumors are most often found in the duodenal wall, and frequently they may be no greater than 2 mm in diameter. Five recent cases illustrate that these small tumors or microgastrinomas may be the sole source of hypergastrinemia and can be cured by local excision. These recent cases emphasize that microgastrinomas are not usually palpable through the duodenal wall. They may be detected only after duodenotomy and meticulous evaluation of the mucosa by eversion and direct palpation. Duodenotomy and intraluminal exploration should be considered an essential component of the operation for patients with extrapancreatic gastrinomas.

Cystic neuroendocrine neoplasms of the pancreas and liver.

Four cases involving cystic endocrine neoplasms of the pancreas and liver are reported. Because of their rich collateral blood supply, islet cell tumors of the pancreas, even if large in size, rarely undergo central or cystic degeneration. However, failure to appreciate that a small percentage of these neoplasms may mimic benign pancreatic pseudocysts by their clinical and radiological appearance can lead to inappropriate surgical therapy. Ultrasound, computerized tomography, and/or angiography are rarely helpful in distinguishing between benign and neoplastic cysts. The definitive diagnosis can be made with assurance only by obtaining a generous biopsy of the cyst wall or any intracystic excrescences for histologic examination. Functional cystic tumors of the pancreas or liver should be excised totally whenever possible, and efforts should be made to remove as much of the tumor mass as possible even when a curative resection cannot be accomplished. Internal drainage may be acceptable as palliation for large, unresectable tumors.

Clinical Features of Carcinoid Syndrome and the Use of Somatostatin Analogue in Its Management

A review is given on the clinical features of carcinoid syndrome including symptomatology, diagnostics, biochemistry and treatment. We have reviewed the literature on current therapy of carcinoid patients with special emphasis on the use of the somatostatin analogue SMS 20-1995. In addition, we present data on the effects of SMS 201-995 on indices of a clinical, biochemical and tumor growth. Diarrhea is abolished or significantly reduced in 75% of patients, flushing improves in 100%, wheezing in 100% with a decrease in airways resistance, and in one patient myopathy has improved. Blood serotonin is notoriously resistant to intervention and urinary 5-HIAA will decrease in 75% of causes but subsequently rebounds in 38%. Tumors, in general, continue to grow, but this may be slowed or in rare cases tumor growth is arrested. In individual instances the tumor may even infarct, leading to spontaneous cure. Tumors secreting PP, ACTH and calcitonin may be particularly resistant to treatment, whereas VIP secreting tumors appear to be sensitive.