Aggressive endometriosis: report of a case

A 54-year-old premenopausal woman presented with abdominal pain, constipati on, and raised serum CA-125 levels during routine follow-up of a low-grade endometrial stromal sarcoma with prominent sex cordlike features, which had been treated by vaginal hysterectomy 4 years previously. The findings at l aparotomy included: a 100-mm unilocular thick-walled right ovarian cyst, a solid 25-mm nodule in the left meso-ovarium, and a phlegmonous mass in the wall of the sigmoid colon, which proved to be a pericolic abscess due to di verticular disease. The ovarian cyst was a histologically benign endometrio id cystadenoma with stromal luteinization in the wall. Small islands of mor phologically benign endometrial tissue were present in vessels of the meso- ovarium. The left adnexal nodule exhibited florid morphologically benign en dometriosis, much of which was within and occluding large vascular spaces, and of apparently recent onset. No lesions resembled, in any way, the origi nal stromal sarcoma. There was no evidence of endometriosis elsewhere in th e pelvis or abdomen. The patient has made an uneventful recovery and is bei ng monitored, as before, by tumor markers only. The discordance in morphology between the uterine sarcoma and the subsequen t pelvic lesions was so complete as to raise doubts about any pathogenetic relationship between them. We propose the use of the term aggressive endome triosis to describe the changes observed.