Medical Care:
" Chemotherapeutic treatment of metastatic somatostatinoma usually consists of combination treatment with intravenous 5-fluorouracil (5-FU) and streptozotocin. Somatostatinomas are very rare; therefore, assessing the efficacy of chemotherapy is difficult, although up to 50% of patients have had an objective humoral and clinical response to this treatment. Doxorubicin and 5-FU have also been used and may be a more effective combination. Palliative hepatic embolization or chemoembolization is another treatment option for patients with unresectable hepatic metastatic disease.
" Patients with metastatic and unresectable somatostatinomas also require specific symptomatic treatments. Associated diabetes can usually be controlled with oral agents and rarely requires the use of insulin. Pancreatic enzyme supplementation is useful to reduce diarrhea and steatorrhea.
Surgical Care:
" Surgical resection is the only option that offers the hope of cure. The goals of surgical therapy are the same as for any pancreatic endocrine neoplasm, as follows:
o To control symptoms of hormone excess
o To safely resect maximal tumor mass
o To preserve maximal pancreatic parenchyma
" Though most somatostatinomas are localized preoperatively, surgical exploration begins with a complete evaluation of the pancreas and peripancreatic regions. Dividing the gastrocolic ligament exposes the body and tail of the pancreas. This portion of the pancreas can be partially elevated out of the retroperitoneum by dividing the inferior retroperitoneal attachments to the gland. After the second portion of the duodenum has been elevated out of the retroperitoneum using the Kocher maneuver, the pancreatic head and uncinate process are palpated bimanually. The liver is carefully assessed for evidence of metastatic disease. Though somatostatinomas are less likely to originate from extrapancreatic locations than gastrinomas, evaluate potential extrapancreatic tumor sites. Evaluation includes inspection, palpation, and ultrasonographic examination of the duodenum, splenic hilum, small intestine (and its mesentery), peripancreatic lymph nodes, and, in women, the reproductive tract.
" Small (<2 cm) benign lesions that are remote from the main pancreatic duct may be enucleated. Regional pancreatectomy is usually necessary for tumors that are deep in the substance of the pancreatic gland (and therefore near the main duct), have ill-defined capsules, or are large (>2 cm). Tumors in the body or tail of the pancreas can be managed with distal pancreatectomy, whereas lesions in the head or uncinate process of the gland can be resected via pancreaticoduodenectomy. Tumors in the neck of the pancreas can be managed with middle segment pancreatectomy (oversewing the proximal pancreatic stump and draining the distal pancreatic duct via pancreaticogastrostomy or pancreaticojejunostomy).
" Debulking cytoreductive surgical resection of liver metastases can be performed in patients with limited hepatic spread. Unique among surgical treatment of pancreatic endocrine tumors, perform cholecystectomies during the first exploration of patients with somatostatinomas, so that if recurrence develops, cholelithiasis will not add to patient morbidity.
Diet: Fluid, electrolyte, and nutritional deficits are common complications of somatostatinoma syndrome. Patients in hormone-excess states may require parenteral supplementation.
Activity: Encourage patients to engage in activity as tolerated. No specific activity requirements or restrictions exist.
DRUG TREATMENT :
1. ANTINEOPLASTIC AGENTS :
- STREPTOZOCIN
- FLUOROURACIL
- DOXORUBICIN