Ectopic endometriosis presenting as a breast abscess in a teenager

Ectopic endometriosis is a gynecologic disorder which is defined by the presence of endometriumtissue outside the uterus. Isolated breast involvement is a very uncommon manifestation of ec-topic endometriosis. We present a 16-year-old girl with compliant of left breast pain, fever, andbreast enlargement from 3 days ago. The ultrasound of left breast showed a well-defined hetero-geneous mass lesion with thick turbid fluid components measuring 6 × 3.5 cm, consistent withabscess formation. The mass was surgically excised without complication. The histopathology re-ports confirmed the left breast endometriosis. The main purpose of this report is for physicians toconsider this diagnosis when facing an unusual manifestation of endometriosis, especially in ar-eas where the prevalence of this disease is rare.