[Bladder leiomyosarcoma. Report of a new case].

Non-epithelial bladder tumours are rare and account for 1% to 5% of all vesical tumours. Among them, malignant muscular sarcoma, myosarcoma, leiomyosarcoma and rabdomyosarcoma account for 0.5% of all malignant vesical tumours. Because of their rarity, a new case of vesical leiomyosarcoma is presented. The clinical, diagnostic and therapeutical aspects are evaluated. Due to its aggressiveness and speed growth, there is no effective treatment, since in most cases both surgery, and radiation plus chemotherapy fall behind the tumour's evolution.