acid-phosphatase and Carcinosarcoma

A very rare case of carcinosarcoma of the prostate is reported. The patient was a 77-year-old man in whom both primary and metastatic tumors presented the pathology of carcinosarcoma of the prostate. The carcinosarcoma was resistant to anti-androgen therapy, and the patient showed low level of serum prostatic acid phosphatase and was free from bony metastases despite multiple metastases to the lung, liver, pancreas, para-aortic lymph nodes, spleen and penis. The sarcomatous component consisted of chondrosarcoma and fibrosarcoma, both of which were positive for vimentin. The carcinomatous component was positive for both keratin and prostatic acid phosphatase.

Topics: Acid Phosphatase; Aged; Carcinosarcoma; Humans; Immunohistochemistry; Keratins; Male; Prostatic Neoplasms

Immunoperoxidase staining of tissue for prostatic acid phosphatase has been useful in confirming the prostatic origin of metastatic deposits. This technique was used on the prostate tumors of 2 patients to differentiate between a true carcinosarcoma and a pure epithelial carcinoma with sarcomatoid changes. Positive staining for prostatic acid phosphatase in both the sarcomatoid element, as well as the area of well-differentiated carcinoma, confirmed the common epithelial cell origin of these components. Electron microscopy further confirmed these findings by demonstrating desmosomes in the sarcomatoid areas. Although each type of tumor is rare, differentiation between true carcinosarcomas and true carcinomas with sarcomatoid changes is important to elucidate further their different clinical behaviors and responses to therapy.

Topics: Acid Phosphatase; Aged; Carcinoma; Carcinosarcoma; Diagnosis, Differential; Humans; Immunoenzyme Techniques; Male; Prostatic Neoplasms; Sarcoma