Incidental Detection of Neuroendocrine Carcinoma of Rectum During Staging Workup of Renal Cell Carcinoma.

Malignancies of rectum and kidneys are common pathologies in clinical practice; however, the incidence of these malignancies coexisting together is unclear. The main purpose of this article was to show the usefulness of computed tomography (CT) in diagnosing these rare synchronous tumors. We report a case of neuroendocrine carcinoma of the rectum in a 57-year-old male patient who came for staging workup of renal cell carcinoma (RCC) of the left kidney. To our knowledge, this is the first case of synchronous RCC and rectal neuroendocrine carcinoma coexisting in the same patient.