Limited information is available regarding the use of androgen receptor (AR) immunohistochemical expression in muscle-invasive or metastatic urothelial carcinoma. We aimed to evaluate the frequency of AR expression by tumor cells (TC), its prognostic role, and its relationship with programmed cell-death ligand 1 (PD-L1) expression in these patients.
From September 2015 to January 2017, we collected tissue from patients who received platinum-based chemotherapy at our center. Immunohistochemistry for AR was performed (1% cutoff of TC). PD-L1 coexpression, by TC or immune cells (1% cutoff), was also analyzed. Molecular analysis of AR gene was performed by sequencing of exons 5 to 8 and by fluorescence in-situ hybridization analysis. Cox models for overall survival (OS), adjusted for stage, visceral metastases, and platinum type, were fitted.
A total of 110 patients had tumor samples stained. Overall, 48 (43.6%) had AR-expressing TC: 19 (17.3%) had 1%-5% expression, 15 (13.6%) 5%-25% expression, and 14 (12.7%) > 25% expression. Among the latter, 7 had molecularly evaluated tumor tissue: no AR gene mutations or amplifications were found, but polysomy of Xq chromosome was seen. PD-L1 expression by TC and immunohistochemistry concordantly decreased with increasing levels of AR expression by TC. In Cox analyses, AR expression was not associated with OS, both on univariable (P = .477) and multivariable (P = .505) analyses.
AR is frequently expressed in patients with muscle-invasive and advanced urothelial carcinoma, and it does not seem to be prognostic for OS. The AR pathway is worthy of clinical studies to assess its synergistic action with anti-PD-L1 therapy.
Clinical genitourinary cancer. 2017 Oct 07 [Epub ahead of print]
Andrea Necchi, Salvatore Lo Vullo, Patrizia Giannatempo, Daniele Raggi, Federica Perrone, Nicola Nicolai, Mario Catanzaro, Davide Biasoni, Tullio Torelli, Luigi Piva, Silvia Stagni, Roberto Salvioni, Luigi Mariani, Maurizio Colecchia
Department of Medical Oncology, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy. Electronic address: ., Medical Statistics, Biometry and Bioinformatics, Unit of Clinical Epidemiology and Trial Organization, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy., Department of Medical Oncology, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy., Department of Pathology and Laboratory Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy., Department of Surgery, Urology Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy.