Caesarean scar endometriosis: how to make an accurate diagnosis

Caesarean scar endometriosis is a rare condition characterised by the presence of endometrial tissue within a surgical scar following a caesarean section. A woman in her late 30s presented with a painful lump beneath her caesarean section skin scar, worsening during menstruation. Despite a previous incision and drainage procedure for a 'scar abscess', the symptoms persisted. Ultrasound imaging revealed a cystic lesion beneath the scar. A diagnosis of scar endometriosis was made, and surgical excision was performed. The patient remained symptom-free at 2-year follow-up postsurgery. Histopathology confirmed the presence of endometrial glands and stroma within the scar tissue. This case demonstrates that a reliable diagnosis of caesarean section endometriosis could be made with a triad of symptoms of a cyclic painful mass at the site of a caesarean section scar. Imaging is helpful in excluding other differential diagnoses. Diagnosis can be confirmed with histopathology and treated with complete surgical excision.