Ureteric obstruction: an unusual presentation of metastatic colon carcinoma

We present the case of a 78-year-old male who presented to clinic for follow-up of a papillary transitional cell carcinoma of the urinary bladder. Notably, the patient also had a history of colorectal resection for an adenocarcinoma. The follow-up appointment revealed left hydronephrosis with evidence of a distal ureteric stricture. Cytology and biopsy from the ureter subsequently disclosed the presence of malignant cells that were originally thought to be of urothelial origin. Upon surgical resection the lesion was found to be an adenocarcinoma, morphologically consistent with a metastasis from the patient's primary colonic adenocarcinoma. This case illustrates a diagnostically challenging situation, with metastatic colonic carcinoma to the ureter occurring in a patient with two previously documented malignancies.