Ureteroscopic diagnosis of intraluminal metastatic rectal carcinoma.

Ureteral obstruction resulting from metastatic adenocarcinoma is almost always extrinsic in nature. In contrast, true intraluminal metastases are extremely rare. With this report, we document the videoendoscopic appearance of true intraluminal ureteral metastases from metastatic rectal cancer confirmed with histopathologic examination. The value of transureteroscopic biopsy for accurate diagnosis is also demonstrated.