A Rare Case of Hematuria from Colonic Adenocarcinoma Spreading to the Bladder via the Stented Ureter

Abstract

Background The direct extension of advanced tumors from adjacent organs to the bladder is not uncommon. Secondary bladder involvement through hematogenous and/or lymphatic metastases and implant of cells by tumors involving higher urinary tract via the ureter are rare. Therefore, the histological resemblance between primary bladder adenocarcinoma and colorectal adenocarcinoma can be a dilemma for pathologists. Methods A 67-year-old female underwent total right hemicolectomy for ascending colon adenocarcinoma. After a 20-month follow-up the lesion was removed (which was histopathologically similar to the previous colon cancer) and the patient underwent ureteral stenting because of a mass in the right internal iliac nodes with homolateral hydronephrosis. Subsequently intermittent gross hematuria urged on performing cystoscopy detecting a non-papillary mass situated above the right ureteral orifice, previously revealed on ultrasonography and CT scan. Results A TURBT was performed. Histopathologically the mass, partially covered by intact urothelium, consisted of tubular and pseudoglandular structures intermixed with solid foci of mucin-producing signet-ring-cells-type adenocarcinoma, very similar to the original colon cancer. The tumor base was healthy. Immunohistochemically stains for cytokeratin 7 (CK7) and cytokeratin 20 (CK20) presented multifocal positivity, suggesting the colorectal origin of the neoplasm. Conclusions In order to optimize the therapeutic options, it is important to distinguish the primary disease of the bladder from other causes of hematuria, and achieve a correct differentiation between primary enteric-type adenocarcinoma of the bladder and secondary colorectal adenocarcinoma involving the bladder, these entities being morphologically indistinguishable. Therefore, in patients with history of colonic adenocarcinoma, the presence of a subsequent bladder tumor should be considered as an eventuality of a secondary disease.