Expression of PDL1 (B7-H1) Before and After Neoadjuvant Chemotherapy in Urothelial Carcinoma

Expression of the costimulatory ligand PDL1 (B7-H1) on tumors allows escape from antitumor immunity. PDL1 expression has been reported in urothelial carcinoma (UC), suggesting it could be used as an immunotherapy target. We investigated the impact of cytotoxic neoadjuvant chemotherapy (NAC) on PDL1 expression in UC. Immunohistochemical staining for PDL1 was performed using an anti-B7-H1 monoclonal antibody (5H1) on a tissue microarray with matched pre-NAC and post-NAC UC samples from 40 patients treated between 1999 and 2011. PDL1 expression was significantly higher in post-NAC specimens than in matched pre-NAC specimens (p = 0.0235, Wilcoxen's signed rank test). PDL1 expression in pre-NAC tissue did not correlate with clinical or pathologic stage but was associated with recurrence free survival. The increase in PDL1 expression following NAC in our limited cohort has potential to guide optimal combination and sequencing of immune and cytotoxic therapies in UC patients. Patient summary: We investigated the relationship between levels of the drug target PDL1 before and after chemotherapy in patients with bladder cancer. We found that levels of PDL1 increased following chemotherapy. We conclude that this information may help doctors in optimizing the sequence of therapies in bladder cancer. (C) 2015 European Association of Urology. Published by Elsevier B.V. All rights reserved.