[Undifferentiated prostate sarcoma with cartilage metaplasia: a case report and review of the literature].

OBJECTIVE: To investigate the clinical presentations and pathologic features of undifferentiated sarcoma of the prostate with cartilage metaplasia, and to clarify its category. METHODS: We analyzed the clinical data of a case of undifferentiated sarcoma of the prostate with cartilage metaplasia treated by surgical resection. The tumor tissue was subjected to routine HE and immunohistochemical staining, its histological structure and immunohistochemical expression were observed under the light microscope, and relevant literature on its manifestations was reviewed. RESULTS: The case was pathologically diagnosed as gray prostate tumor, with chondrosarcomatous and undifferentiated malignant mesenchymal components under the light microscope. Immunohistochemical staining revealed vimentin (+), local CD117 (+/-), SMA (-), Des (-), myoglobin (-), CD34 (-), CK7 (-), and CK8 (-). Tumor metastasis was found 2 months after the operation, and the patient died 4 months later. CONCLUSION: Undifferentiated sarcoma of the prostate with cartilage metaplasia is a very rare and highly malignant aggressive tumor, which can be diagnosed by biopsy and immunohistochemistry.