The patient is a 26 year old female with history of umbilical pain, cyclical with menstrual cycle, and with some cyclical discharge. Examination reveals two pink nodules in the umbilicus. A biopsy is performed.
Diagnosis: Cutaneous endometriosis.
Discussion: Cutaneous endometriosis is a subset of extrapelvic endometriosis presenting at a mean age of 34 years and represents 8.9% of reported cases of endometriosis. The most common presentations are a nodule within a Caesarean section or other pelvic surgery scar or a spontaneously appearing nodule at the umbilicus. Spontaneous cutaneous endometriosis, as seen in this case, represents less than 1% of all cases of extragenital endometriosis. Histologic diagnosis depends on the finding of endometrial glands and stroma in the dermis. There are often signs of recent and remote hemorrhage in the form of extravasated red blood cells and hemosiderin deposition. There may be variable acute and chronic inflammation.
References: Douglas C, Rotimi O. Extravaginal endometriosis: a clinicopathologic review of a Glasgow hospital experience with case illustrations. J Obstet Gynaecol 2004;24:804-8.