Inguinal endometriosis in a patient without a previous history of gynecologic surgery
A 40-year-old nulliparous woman presented with a painful mass in her right inguinal area. The mass had grown for 2 years and had occasionally been tender, especially during menstrual cycles. The patient had no specific medical or surgical history. She experienced regular menstruation at 30-day intervals and experienced menorrhagia. Her menstruation period lasted 7 days.\nPhysical examination revealed a non-erythematous swollen and tender mass measuring approximately 2×2 cm located lateral and superior to the pubic tubercle. The size and position of the mass remained unchanged, even when the patient coughed or changed positions. The patient also reported intermittent vaginal spotting, for which she had undergone simultaneous transvaginal and inguinal ultrasonography.\nThe transvaginal ultrasonography revealed two left ovarian cysts measuring 1.0 cm that seemed to be endometrioma or hemorrhagic corpus luteal cysts (). Inguinal ultrasonography showed an ill-defined hypoechoic lesion (size, 1.1×1.2 cm) in the right pubic area, with increased vascularity (). She underwent repeated inguinal ultrasonography during her menstrual period. She felt tenderness and swelling of the lesion, but there was no change of mass size on inguinal ultrasonography. After being informed about the presence of hemangioma or arteriovenous malformation, the patient opted for surgical excision of the inguinal mass.\nAn oblique skin incision was performed along the line running from the pubic tubercle to the anterior superior iliac spine, at the superior margin of the inguinal ligament. After identification of the femoral vessels, the hard mass was widely excised to include a part of the round ligament. Chocolate-colored fluid was drained from the hard cystic mass during the procedure, and the mass was connected with the intraperitoneal round ligament at the inguinal canal. The inguinal canal was opened and the extraperitoneal portion of the round ligament was resected by gentle traction and then cutting at the level of the internal inguinal ring. The proximal stump was fixed to the surrounding fibrous structure of the inguinal canal. Histological examination showed a cuff of endometrial stroma surrounding the endometrial glands with hemorrhaging from smooth muscle and fibrous tissues (). After 2 months of the surgery, the patient's pain completely resolved and she was fully recovered without complications. Considering the possibility of recurrence of the inguinal endometriosis and progression of the ovarian endometrioma, we recommended her to use the oral contraceptives and planned regular follow-up.