Primary Periumbilical Endometriosis Mimicking Umbilical Hernia in a 37-Year-Old Woman: A Report of a Rare Case.

This case report describes a rare presentation of primary periumbilical endometriosis, also known as Villar's nodule, highlighting the diagnostic difficulties and the importance of maintaining clinical suspicion. A 37‑year‑old woman presented with a one‑year history of cyclical periumbilical pain along with severe menorrhagia and dysmenorrhea. Initial ultrasonography suggested an umbilical hernia, but subsequent imaging, including repeat ultrasound and contrast‑enhanced MRI, revealed subcutaneous periumbilical nodules without evidence of intraperitoneal extension or associated pelvic endometriosis. An incidental intramural uterine fibroid was also noted. The patient underwent surgical excision of the periumbilical nodules along with myomectomy. Histopathological examination confirmed the diagnosis of endometriosis. Her postoperative recovery was uncomplicated, and she remained asymptomatic at the six‑month follow‑up. This case underscores the need to consider primary periumbilical endometriosis in women presenting with cyclical umbilical pain and demonstrates that early diagnosis and complete surgical excision can lead to favorable clinical outcomes.