Carcinoid tumor of the kidney: case report and review of the literature.

Carcinoid tumors are low-grade malignant tumors that arise from neuroendocrine cells. Primary renal carcinoid tumors are extremely uncommon. They seem to be more indolent than renal cell carcinomas, although metastases to regional lymph nodes, liver, and bone have been described. The presence of metastases seems to indicate a more malignant course; however, even with metastases a patient might live for 3 or 4 years. Renal carcinoid tumors should be managed by radical or partial nephrectomy, and good outcomes have been obtained for organ-confined disease after radical excision. Conventional methods of imaging are inadequate for detecting smaller carcinoids, so somatostatin receptor scintigraphy should complement computed tomography and magnetic resonance imaging when searching for occult or metastatic disease. Close follow-up after surgery is necessary.