TERT- beyond the territory: Usage of PCR-based TERT promoter assay in defining urothelial carcinoma in a case of long-standing prostatic adenocarcinoma.

Bladder cancer continues to be a source of disease burden worldwide. In patients with a long-standing history of prostate cancer, distinguishing between new/independent and synchronous poorly differentiated urothelial carcinoma and residual/recurrent high grade/poorly differentiated prostatic adenocarcinoma or prostatic adenocarcinoma with therapy-related changes can be diagnostically and therapeutically challenging. In the present case report, along with morphological features, immunohistochemical (IHC) studies and a novel polymerase chain reaction (PCR) based telomerase reverse transcriptase (TERT) promoter mutation assay were used as essential ancillary tools in reaching a final diagnosis. This is important as spatially, topographically and temporally multi-focal and multi-differentiating tumors can behave differently with different prognostic and therapeutic connotations.