1998 Volume 59 Issue 5 Pages 1385-1388
External endometriosis is a condition in which tissue like that of the uterine mucosa occurs outside the uterus. External endometriosis arising in the skin represents about 1.1% of all cases of endometriosis, and among of them, umbilical endometriosis is very rare that occupies about 30%. This paper presents a recent case of umbilical endometriosis.
A 46-year-old woman was admitted to the hospital because of an umbilical tumor. Hemorrhage from the foramen in the center of the tumor was recognized during menstrual period. She was diagnosed as having umbilical endometoriosis. Excision of the umbilical tumor under laparotomy was performed. Omphaloplasty was performed using a free skin flap to repair a skin defect at the umbilical region. Pathologically it was umbilical endometoriosis having the structure with tubular pattern like endothelium of the uterus.
The histogenesis of the external endometoriosis is not known, but there are four hypotheses; (1) retrograde menstruation, (2) a result of endometrial metaplasia of the peritoneal serosa, (3) mechanical transplantation in surgical scar, and (4) vascular or lymphatic dissemination. The umbilical endometoriosis as observed in this case supports the fourth hypotheses.