Umbilical Endometriosis

— A Case Report —

Abstract

A 37-year-old Japanese woman presented with a tender tumor in her navel in March 2009. She had noticed the tumor in October 2008, which gradually enlarged and was sometimes tender, though she thought that the occasional tenderness coincided with her period. On examination, a hard intradermal tumor, about 1 cm in diameter, was palpable on the right wall of the navel. The overlying skin showed brownish pigmentation. The tumor was excised under local anesthesia. Histological examination revealed endometrial glands and stroma in the dermis with focal siderophages. Review of the literature showed that endometriosis commonly occurrs in the ovaries, pouch of Douglas, uterine ligament, pelvic peritoneum, and other pelvic spaces, but rarely in the skin or subcutaneous tissue. However, it occurs in 40% of female navel tumors.