A mysterious case series of scar endometriosis

Abstract

Scar endometriosis is an uncommon form of extrapelvic endometriosis that most frequently develops following obstetric or gynaecological surgery, particularly caesarean section. Because its clinical presentation may mimic other scar-related lesions, diagnosis is frequently delayed. A painful scar-associated mass with cyclical variation in symptoms should raise suspicion of scar endometriosis. We present a retrospective case series of 3 women diagnosed with scar endometriosis at MCH Holenarasipura between January 2026 and June 2026. Clinical presentation, previous surgical history, imaging findings, operative findings, treatment and histopathological confirmation were reviewed. The three patients were aged 24, 26 and 27 years. All had a previous history of caesarean section. The interval between the preceding surgery and presentation was 18 months, 24 months and 16 months. The predominant clinical presentation was a painful scar-associated swelling, with all three patients reporting cyclical exacerbation of pain during menstruation. Ultrasonography was performed in all patients; MRI was not performed in any patient. All three patients underwent wide local excision of the endometriotic lesion. Histopathological examination demonstrated endometrial glands and stroma within fibrous and/or skeletal muscle tissue, confirming scar endometriosis. Scar endometriosis should be considered in the differential diagnosis of a painful abdominal or pelvic surgical scar, particularly in women with a previous caesarean section. A high index of suspicion, appropriate ultrasonography and complete surgical excision with histopathological confirmation are important for definitive treatment and prevention of recurrence.