Prostatic carcinosarcoma seven years after radical prostatectomy and hormonal therapy for prostatic adenocarcinoma: A case report

BACKGROUND Prostatic carcinosarcoma is a very rare and highly aggressive tumor. It may occur after androgen deprivation therapy (ADT) for adenocarcinoma even after a 7-year interval. CASE SUMMARY A 66-year-old man presented with recurrent symptoms of gross hematuria and urinary retention. The patient had a previous history of combined radical prostatectomy and ADT for prostate cancer 7 years prior. He received total pelvic exenteration for a recurrent pelvic carcinosarcoma. Pathology and immunostaining revealed a carcinosarcoma of prostatic origin with focal spindled cells and bizarre giant cells. The patient subsequently underwent transverse colostomy for carcinosarcoma recurrence and bowel obstruction 3 mo later. Five months after the diagnosis of prostatic carcinosarcoma, the patient died of multiple organ metastases. CONCLUSION Prostatic carcinosarcoma after adenocarcinoma is exceedingly rare. ADT mediated transformation and dedifferentiation of the epithelial components may be the origin of this malignancy.