Current management of gastrointestinal carcinoid tumors.

Gastrointestinal carcinoid tumors are rare neuroendocrine tumors arising from the embryologic primitive gut. Depending on the location in the gastrointestinal tract, these tumors may secrete a variety of hormonally active substances. However, many of these tumors are found incidentally, or the diagnosis is made postoperatively. Also, there is a significant incidence of multicentric carcinoid tumors and synchronous noncarcinoid malignancies in these patients. Treatment is usually based on the size of the tumor. Surgical resection remains the cornerstone of therapy. For advanced metastatic disease, somatostatin analog therapy and surgical debulking provide the best symptomatic relief and may improve survival. Recent studies have demonstrated a benefit from radiolabeled somatostatin analogs for carcinoid tumor localization. In contrast, radiolabeled somatostatin analogs have shown little therapeutic benefit. Future directions include somatostatin receptor profiling of carcinoid tumors, with somatostatin analog therapy targeting the specific receptors.