Background: The presence of ectopic functional endometrial glands and struma anywhere except in the lining of the uterine cavity is considered as endometriosis. Extrapelvic endometriosis involving the abdominal wall cesarean section scar is uncommonly seen, and it rarely involves the perineum, umbilicus, pleura, kidneys, lungs and liver. Objectives: The purpose of the present study is to highlight rare ectopic sites, explain the pathogenesis of extrapelvic endometriosis, and evaluate the diagnostic significance of clinical findings, serum CA 125 level, and ultrasonography. Materials and methods: 24 female patients with extrapelvic endometriomas in whom the final diagnosis was based on the surgical results and histopathological reports of the excised specimens. The patients underwent a clinical examination, an ultrasound scan, and evaluation of the serum CA 125 level. They were also examined by transvaginal ultrasound to rule out ovarian endometriosis or uterine adenomyosis. They were further subjected to abdominal wall ultrasound in cases of cesarean section scar or umbilical region swellings, and transperineal ultrasound for perianal lesions. Transvaginal ultrasound was performed in patients with perineal endometrioma to assess the relation between the lesion and the external anal sphincter. Results: In 19 patients, abdominal wall cesarean section scar endometrioma was detected. Three patients had perianal endometriomas, and two patients – umbilical endometriomas. Conclusion: Ultrasound scanning was a useful diagnostic tool to evaluate extrapelvic endometriosis and its extension, especially in cases without typical clinical features that can be suggestive of endometrioma, low diagnostic sensitivity of serum CA 125, and low incidence of concomitant intrapelvic disease.

extrapelvic endometriosis, cesarean section scar endometrioma, perineum endometrioma, umbilicus nodule