Carcinosarcoma prostate with osteosarcomatous differentiation: a rare de novo presentation.

Carcinosarcoma is a rare histological event in the history of prostatic malignancies. Historically aggressive tumours with dismal outcomes reported in scarce literature available so far. Very few recent studies suggest good outcomes with modern era surgery and radiotherapy techniques in localised disease. The case presented here had no history of known risk factors like prior adenocarcinoma or prior radiation therapy. This case presented with obstructive urinary symptoms with no prostate-specific antigen elevation, diagnosed with imaging, managed aggressively with robotic surgery. Detailed immunohistochemistry and pathological review suggested diagnosis as carcinosarcoma with osteosarcomatous differentiation. Very rare such cases were reported in the past with complete clinical, radiological, pathological details and managed aggressively with good outcomes. The patient is disease free after 6 months of follow-up. © BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.