[Primary endometriosis of the abdominal wall: an entity to be included in the differential diagnosis of abdominal wall masses]. / Endometriosis primaria de pared abdominal, una enfermedad que debe ser considerada en el diagnóstico diferencial de las tumoraciones de la pared abdominal.

Endometriosis consists of the presence of extrauterine endometrial tissue. It is usually localized in the pelvis, although it can also be found in other sites. Cutaneous localization is unusual and the most frequent form appears on scars from obstetric or gynecological interventions. It can, however, develop spontaneously, especially in umbilical or inguinal areas and can be confused with irreducible hernias or granulomas. We present the cases of three patients with spontaneous endometriotic nodules of the abdominal wall. The lesions were located in the umbilical region in two patients and in the suprapubic area in one. In two patients clinical suspicion led to preoperative diagnosis, although diagnosis is usually established after histopathological analysis of the surgical specimen.