CARCINOSARCOMA OF THE PROSTATE - REPORT OF 21 CASES

Background, Carcinosarcoma of the prostate is an unusual malignancy ch aracterized by adenocarcinoma intimately admired with sarcoma. Methods . The authors reviewed the clinical and pathologic findings of 21 case s of carcinosarcoma of the prostate from the files of the Mayo Clinic. Results, Patient age ranged from 50 to 89 years (mean, 68 years). Ten patients (48%) had a previous diagnosis of prostatic acinar adenocarc inoma 2-73 months (mean, 33 months) before the diagnosis of carcinosar coma, 8 of whom had received androgen deprivation therapy and/or or ra diation therapy in the interim, The Gleason score of adenocarcinoma ra nged from 7 to 10 (mean, 9; median, 9), The sarcomas consisted of oste osarcoma (13), leiomyosarcoma (5), fibrosarcoma (1), malignant fibrous histiocytoma (1), and rhabdomyosarcoma (1), and the grade of the sarc oma component ranged from 2 to 4 (mean, 4; median, 4), Adenocarcinoma was the dominant histologic pattern in 7 cases and sarcoma in 14, Immu nohistochemical staining revealed cytoplasmic reactivity for prostate specific antigen or keratin in 16 of 16 cases in the adenocarcinoma co mponent, The sarcoma component was positive for vimentin in 16 of 16 c ases, actin in 8 of 16 (focal in 2), S-100 protein in 2 of 16, and des min in 1 of 16, At the time of diagnosis of carcinosarcoma, 11 patient s had metastases, including 4 with metastatic adenocarcinoma before th e diagnosis of carcinosarcoma, Treatment varied, and nonsurgical thera py was ineffective. Sites of metastases included lung (10 cases), bone (7), brain (4), liver (1), and peritoneum (1). Follow-up ranged from 1 to 107 months after the diagnosis of carcinosarcoma (mean, 34 months ; median, 10 months). Mean time to tumor progression was 23 months (ra nge, 1-96 months; median, 18 months). Eighteen patients died of carcin osarcoma from 2 to 107 months (mean, 34 months; median, 9.5 months) af ter diagnosis, Five-year survival was 41%, and 7-year survival was 14% . Progression and survival were not affected by histologic pattern. Co nclusions, Carcinosarcoma of the prostate is an aggressive malignancy, regardless of histologic type.