[Retrovesical liposarcoma: a case report].

A case of retrovesical liposarcoma is reported. The patient was a 41-year-old man who complained of left scrotal pain and of hip discomfort. Digital rectal examination revealed a hen's egg-sized mass with an elastic hard consistency at the left side of the normal prostate. Pelvic CT and MRI showed a heterogeneous tumor in the retrovesical region. Transperineal biopsy revealed liposarcoma. Pelvic exenteration, colostomy and ileal conduit were performed. The resected weight was 1,680 grams, and the histopathological diagnosis was myxoid type of liposarcoma, grade II. Postoperatively, a metastatic lesion to vertebrae thoracicae I developed causing radiculoneuropathy of the left superior limb. Spot radiation (50 Gy) was administered to the lesion, but there was no response. Currently, the patient is being treated with combination chemotherapy consisting of dacarbazine, vincristine, adriamycin, and cyclophosphamide. Cases of retrovesical liposarcomas reported in Japan are reviewed and discussed.