EP31.20: Ultrasound findings of extraperitoneal endometriosis of round ligament: a case report

A patient, female, 48-year-old, complained of swelling pain occasionally in the right groin mass, and the mass was gradually enlarged. MR suggested that a mass in the right ventral femoral transit area, which was considered to be mostly caused by tumour. Ultrasonography: the right inguinal region showed a hypoechoic mass, clear boundary and the mass appeared to be connected with abdominal cavity. CDFI: A dot-like blood flow signal is visible inside. Postoperative pathology: “Right inguinal mass” adenomyoma. Extraperitoneal inguinal endometriosis was first described by Cullen in 1896. The right side is more common than left side and rarely occurs bilaterally. The round ligament exits the abdominal cavity through the inner ring of the inguinal canal and attaches to the labium majus through the inguinal canal. Extraperitoneal inguinal endometriosis lesions can be solid, cystic or complex cystic and solid components. Imaging features are non-specific but contribute to differential diagnosis. The diagnosis of endometriosis is predisposed to the presence of a cystic mass in the peritoneal sulcus, which varies with the size of the menstrual cycle according to medical history. In this case, the inguinal mass was solid, and the primary soft tissue tumour could not be excluded only by ultrasound imaging. Therefore, combined with the clinical history, it was very important for correct diagnosis. The presence of extraperitoneal endometriosis should be considered in the differential diagnosis of inguinal masses in women of childbearing age. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.