To assess the prognostic and diagnostic utility of PSA immunostaining, tissue microarrays containing 17,747 prostate cancers, 3,442 other tumors from 82 different (sub) types and 608 normal tissues were analyzed at two different antibody concentrations (1:100 and 1:800). In normal tissues, PSA expression was limited to prostate epithelial cells. In prostate cancers, PSA staining was seen in 99.9-100% (1:800-1:100) primary tumors, 98.7-99.7% of advanced recurrent cancers, in 84.6-91.4% castration resistant cancers, and in 7.7-18.8% of 16 small cell carcinomas. Among extraprostatic tumors, PSA stained positive in 0-3 (1:800-1:100) of 19 osteosarcomas, 1-2 of 34 ovarian cancers, 0-2 of 35 malignant mesotheliomas, 0-1 of 21 thyroid gland carcinomas and 0-1 of 26 large cell lung cancers. Reduced staining intensity and loss of apical staining were strongly linked to unfavorable tumor phenotype and poor prognosis (p < 0.0001 each). This was all the more the case if a combined “PSA pattern score” was built from staining intensity and pattern. The prognostic impact of the “PSA pattern score” was independent of established pre- and postoperative clinico-pathological prognostic features. In conclusion, PSA immunostaining is a strong prognostic parameter in prostate cancer and has high specificity for prostate cancer at a wide range of antibody dilutions.

Oncotarget. 2019 Sep 10*** epublish ***

Sarah Bonk, Martina Kluth, Claudia Hube-Magg, Adam Polonski, Greta Soekeland, Georgia Makropidi-Fraune, Christina Möller-Koop, Melanie Witt, Andreas M Luebke, Andrea Hinsch, Eike Burandt, Stefan Steurer, Till S Clauditz, Thorsten Schlomm, Daniel Perez, Markus Graefen, Hans Heinzer, Hartwig Huland, Jakob R Izbicki, Waldemar Wilczak, Sarah Minner, Guido Sauter, Ronald Simon

General, Visceral and Thoracic Surgery Department, University Medical Center Hamburg-Eppendorf, Hamburg, Germany., Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany., Urology Clinic, Charite – Universitätsmedizin Berlin, Berlin, Germany., Martini Clinic, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.