Inguinal Endometriosis in a Nulliparous Woman Mimicking an Inguinal Hernia: A Case Report with Literature Review.

BACKGROUND Endometriosis is a common gynecological disorder occurring in around 10% of women of reproductive age. Inguinal endometriosis is a rare condition; however, it should be considered in the differential for inguinal masses in women of reproductive age. Usually, it occurs after implantation of endometrial tissue during previous surgical procedures. Patients with inguinal endometriosis are often multiparous women with a history of previous gynecological or obstetric surgery. It represents a diagnostic dilemma, as it is often misdiagnosed as other inguinal pathologies. CASE REPORT Herein, we report a case of a 33-year-old nulliparous woman with left groin pain for 2 years increasing in the severity during menstruation. A physical examination revealed a 1.5-cm left inguinal mass. Ultrasound showed an ill-defined speculated solid hypoechoic left inguinal mass measuring 1.6×1.4 cm. Computed tomography (CT) of the pelvis revealed a left inguinal mass measuring 1.7×1.2 cm, demonstrating central hypo-attenuation with thickening of the round ligament. Exploration of the inguinal region revealed an adherent mass to the round ligament and floor of the canal, which was excised completely with a safety margin. The inguinal canal floor was strengthened using proline mesh. Histopathological examination of the mass confirmed the diagnosis of left inguinal endometriosis. CONCLUSIONS Inguinal endometriosis is a rare clinical entity mimicking other common inguinal conditions. A high index of suspicion is crucial for its preoperative diagnosis, especially in the presence of an inguinal mass associated with cyclic changes in size and pain severity. Its standard management is surgical excision.