1/4. Multiple effects of somatostatin analogs verified in three cases of metastasized neuroendocrine tumors of the gastroenteropancreatic system.AIMS AND BACKGROUND: In neuroendocrine tumors of the gastroenteropancreatic (GEP) system, radiolabeled analogs of somatostatin (SST) are useful to the surgeon in different phases of treatment: preoperatively, to identify the lesion with somato-statin receptor scintigraphy (SRS), intraoperatively for localization using a hand-held gamma probe, and postoperatively acting directly to eliminate any residual tumor cells. Additional features of these analogs that are of value in treating such GEP tumors include their antiproliferative potential, which is in the process of being verified, and, above all, their anti-secretory action, so effective in symptom control. In this study the authors, based on their own experience, evaluate the effectiveness of SST analogs in treating GEP endocrine tumors. methods: Three patients with malignant GEP apudomas were studied. In case 1, an insulinoma, the patient underwent four surgical procedures for ablation of the pancreatic tumor and of hepatic and lymph node metastases in addition to local radiofrequency treatment and radiometabolic therapy. Case 2 was a carcinoid tumor of the small intestine with hepatic metastases, managed by ileal resection, local radiofrequency treatment and receptor-mediated radionuclide therapy. In case 3, a non-functioning pancreatic carcinoma with liver and lymph node metastases, the patient underwent four surgical procedures, hepatic chemoembolization, antiproliferative treatment using octreotide (OCT) and metabolic radionuclide therapy. RESULTS: In all three cases SRS proved highly sensitive in the early detection of even the smallest recurrences. There was uncertainty, however, regarding the effectiveness of therapy with radiolabeled SST analogs. Hepatic metastases from the carcinoid were completely unresponsive, but in the case of the insulinoma, the hepatic metastases showed necrosis following treatment, while lymph node metastases were unaffected. In the case of the non-functioning carcinoma, there was a correlation between treatment and a marked improvement in the patient's clinical condition, although the appearance of the lesions themselves remained unchanged. The antiproliferative effect of OCT in this case was nil. CONCLUSIONS: SRS proved highly accurate in detecting recurrences during follow-up. The merits of radiometabolic therapy, on the other hand, were unclear, a finding reported elsewhere in the literature, and in the only case treated by prolonged OCT treatment, no antiproliferative action was observed. The diagnostic usefulness of SRS was thus confirmed and it appears likely that radiolabeled analogs used intraoperatively for tumor localization will prove equally of value. The effectiveness of receptor-mediated radionuclide therapy is still in the process of being verified. Based on the expectation of analogs with an universal affinity for SST receptors (sst), it is reasonable to look forward to a significant increase in the efficacy of this type of therapy.- - - - - - - - - - ranking = 1keywords = endocrine (Clic here for more details about this article) |
2/4. Perioperative use of long-acting somatostatin analog (SMS 201-995) in patients with endocrine tumors of the gastroenteropancreatic axis.The clinical manifestations of hormone excess caused by functioning neuroendocrine tumors of the gastroenteropancreatic (GEP) axis can be life threatening and frequently prove refractory to conventional antisecretory drugs. Administration of a long-acting somatostatin analog (SMS 201-995) proved effective in three patients with complex management problems related to GEP tumors. A patient with an insulinoma was maintained euglycemic intraoperatively with a single 100 micrograms dose of SMS given before surgery. Gastric suction in two patients with gastrinomas caused hypochlorhydric alkalosis that was preventable with preoperative SMS. Iatrogenic pancreatic fistula occurring after resection of a benign insulinoma healed within 4 days of SMS administration. This drug may be a useful adjunct in the perioperative management of patients with GEP endocrine tumors. Caution is advised regarding potential hazards related to malabsorption and gastric dysmotility.- - - - - - - - - - ranking = 1keywords = endocrine (Clic here for more details about this article) |
3/4. Neuroendocrine gut neoplasms. Important lessons from uncommon tumors.OBJECTIVE: To review our experiences in order to high-light some important lessons learned in the treatment of patients with neuroendocrine gut neoplasms. DESIGN: Retrospective analysis of case series of 70 patients with neuroendocrine gut neoplasms treated between 1983 and 1993. The clinical features of individual patients illustrate lessons in surgical treatment. SETTING: University hospitals with tertiary care referral practice. INTERVENTIONS: The main intervention was abdominal exploration in 43 patients, with resection of the primary tumor in 39 and of hepatic metastases in four. MAIN OUTCOME MEASURES: To describe the tumors seen and to identify major lessons learned. RESULTS: Of 70 patients with neuroendocrine tumors treated, 31 had carcinoid tumors, 10 each had insulinomas and gastrinomas, five had vipomas, nine had non-functioning islet cell tumors, three had glucagonomas, and one each had somatostatinoma and a possible cholecystokinin-secreting tumor (or CCKoma). Important lessons learned include: (1) the importance of preoperative tumor localization; (2) in multiple endocrine neoplasia, type I syndrome, the tumor found may not be the one responsible for the patient's symptoms; (3) solitary sporadic tumors secreting multiple peptides may mimic multiple tumors in multiple endocrine neoplasia, type I syndrome; (4) one needs to be prepared for the unexpected, such as the carcinoid crisis; (5) resection may sometimes be necessary even with advanced local disease; and (6) selected patients may benefit from pancreaticoduodenectomy. CONCLUSIONS: These rare tumors are interesting in their clinical presentation and can be challenging in their treatment.- - - - - - - - - - ranking = 1.5keywords = endocrine (Clic here for more details about this article) |
4/4. Endoscopic ultrasonography: a new diagnostic imaging modality.Endoscopic ultrasonography uses high-frequency ultrasound to visualize the gut wall and the surrounding structures of the mediastinum, the abdomen and the pelvis. Echoendoscopes are available in two different designs. A radial scanning echoendoscope produces a 360 degree real-time view perpendicular to the shaft of the echoendoscope. A linear-array instrument produces a 100 degrees real-time view parallel to the shaft of the echoendoscope, permitting direct ultrasonographic guidance of fine needles exiting the biopsy channel. Endoscopic ultrasonography has been established as the preferred diagnostic tool for the evaluation of submucosal masses of the upper gastrointestinal tract and the rectosigmoid, for differentiating benign from pathologic thickened gastric folds and for locating pancreatic endocrine tumors. The widest application of endoscopic ultrasonography is in the diagnosis and staging of esophageal, gastric, rectal and pancreaticobiliary neoplasms. endosonography is the most accurate modality available for determining the T and N stages of these tumors. The recent development of endoscopic ultrasound-guided fine-needle aspiration provides physicians with the ability to cytologically diagnose lesions visualized endosonographically and to confirm cancer staging with tissue.- - - - - - - - - - ranking = 0.16666666666667keywords = endocrine (Clic here for more details about this article) |