[A case report of primary renal carcinoid tumor]

A 54-year-old woman was referred to our institute because of abdominal pain and constipation. The computed tomography of the abdomen revealed a 3 x 3 cm of low density tumor at the upper pole of the left kidney and para-aortic lymphadenopathy. Gastrointestinal investigation revealed no particular findings suggesting a carcinoid syndrome associated with the left kidney tumor. The specimen of the resected tumor showed staining pattern specific to carcinoid tumor; positive staining for chromogranin A and neuron-specific-enolase. Electron microscopy confirmed the presence of dense-core granules in the tumor cells. No evidence of metastasis or recurrence was noted for 13 months after the operation. This was a very rare case of primary renal carcinoid, representing the 26th case in the literature.