[Postoperative pseudosarcomas of the genitourinary tract. A diagnostic trap. Presentation of 4 cases of which 2 were studied immunohistochemically and review of the literature].

Four cases of postoperative pseudosarcomatous nodules of the genitourinary tract are reported. Two occurred in the vagina of 38 and 57 year-old women, 1 and 3 months after vaginal hysterectomy. The third one occurred in the bladder of a 60-year-old man, 1 and 1/2 months after prostatic adenomectomy. The fourth one occurred in the bladder of a 60-year-old woman, 2 months after transurethral cystoscopy with biopsies. On microscopic examination, the lesions were cellular spindle cell proliferations with numerous mitoses and minimal or no cytonuclear atypia. They mimicked sarcoma, with an overall appearance suggestive of leiomyosarcoma. Immunohistochemical studies performed on 2 cases showed strong reactivity of the cells with vimentin. Cytokeratins, desmin, smooth muscle myosin, smooth and striated muscle actins and factor VIII were negative. Despite simple, sometimes partial, local excision of the nodules, there was neither recurrence nor metastasis 8 months to 5 years later.