Isolated perineal endometriosis? Yes ... an exceptional location.

Endometriosis is a nonmalignant condition characterized by the growth of endometrial tissue outside the uterus. Perineal endometriosis, an uncommon occurrence, involves the presence of endometrial tissue in the superficial perineum. In this report, we present a unique case of a 40-year-old woman with no known history of endometriosis. She had undergone an episiotomy 10 months prior and presented with swelling in the left perineal region, with no signs of inflammation or fever. To investigate the condition, a pelvic MRI was performed, revealing a rounded collection in the left perineal area, leading to the suspicion of perineal endometriosis based on the patient's pain pattern and medical history. The diagnosis was subsequently confirmed after drainage.