Nonsurgical Treatment of Advanced Malignant Neuroendocrine Pancreatic Tumors and Midgut Carcinoids

Abstract.

Neuroendocrine enteropancreatic tumors are relatively uncommon and present variable biologic and clinical features. Surgery at early disease stages is currently the only available cure. Evidenced-based medicine and consensus on systemic treatment of advanced malignant disease is virtually nonexistent, and the various available therapeutic regimens should be considered primarily palliative. Symptomatic treatment of patients with endocrine functioning tumors, however, is of utmost importance and leads to extensive prolongation of survival. Biotherapy by means of somatostatin analogs and interferon-α facilitates symptomatic control and offers stabilization of tumor progression for extended periods of time. Pancreatic endocrine tumors metastatic to the liver frequently respond to chemotherapy by means of a significant reduction in tumor volume. Programs including streptozotocin and 5-fluorouracil or doxorubicin are generally regarded as first line treatment for pancreatic endocrine tumors with liver metastases, whereas midgut carcinoid tumors often are resistant to systemic chemotherapy. Treatment attempts in patients with the latter disease may rather include interferon-α and somatostatin analogs. Somatostatin receptor-targeted radiotherapy is still investigational. Repeated surgical intervention including various debulking procedures should be considered here and in patients with advanced neuroendocrine pancreatic tumors and midgut carcinoids requiring systemic antitumor treatment.