Does Variant Histology Change Management of Non-muscle-invasive Bladder Cancer?

Abstract

A 52-yr-old man, 35 pack-year smoker, is diagnosed with two non-muscle-invasive urothelial tumors, pTa and pT1, the former upstaged to pT1 by a reference pathologist. Two possible treatment strategies include intravesical bacillus Calmette-Guérin (BCG) and/or primary or rescue cystectomy. The importance or even accurate existence of "variant histology" is put into perspective, and whether the reference pathologist's diagnosis of a micropapillary variant requires a real change in treatment strategy is considered. PATIENT SUMMARY: The reference urologist diagnosed two small bladder tumors as two different depths of infiltration: one as pTa and the other (slightly more severe) as pT1. Suspecting a variant, the reference urologist referred to a second pathologist, who upstaged the less severe tumor to T1, with both defined as micropapillary cancer. This presentation discusses removal of the bladder versus a trial of treatment with bladder preservation.

Keywords: Bacillus Calmette-Guérin; ERBB2; HER2; Micropapillary differentiation; Radical cystectomy; Variant histology.