Unexpected diagnosis of stage IIA dysgerminoma in streak gonad in a patient with Swyer syndrome: a case report

A Case of Swyer Syndrome Complicated with Left-sided Gonadoblastoma and Asexual Cell Tumor

Introduction: 46,XY pure gonadal dysgenesis (PGD) is also known as Swyer syndrome. The chromosome analysis indicates a 46,XY karyotype. As different degrees of gonadal hypoplasia or degeneration occur in the process of embryonic development due to several factors, gonadal dysplasia or gonadal tumors are probable. Case Presentation: The patient was a 22-year-old female with no menstruation during puberty. Her chest was funnel-shaped, the breast development was classified as Tanner III grade, the vulva was normal, the pubic hair was classified as Tanner II grade, and the vaginal long was 6 cm. The endocrine examination indicated a follicle-stimulating hormone level of 95.0 mIU/mL and an estradiol level of 34.0 pg/mL. Tumor markers, including alpha-fetoprotein (AFP), carbohydrate antigen 125 (CA125), carbohydrate antigen 199 (CA199), and carcinoembryonic antigen (CEA), were normal. Dual-energy X-ray absorptiometry revealed that the bone mineral density was lower than the normal range at this age. Ultrasonography showed a hypoechoic mass in the left adnexal area, considering gonadal tissue with calcification. Pelvic MRI indicated a gonadal malignancy, and the gonadal tissue of the right adnexal area was cord-shaped. The chromosome analysis indicated a 46,XY karyotype. Accordingly, a clinical diagnosis of PGD was established. Moreover, laparoscopic gonadectomy and pathological examination were performed, and a final diagnosis of Swyer syndrome, complicated with a left-sided gonadoblastoma and asexual cell tumor, was made. Conclusion: PGD is associated with a high risk of gonadal tumors. Considering the rarity of this disease, a detailed evaluation of gonadal size and timely preventive gonadectomy are recommended for patients with gonadal dysplasia. Overall, imaging examinations can provide important information for the diagnosis of gonadal dysplasia. MRI can clearly indicate the size and shape of the gonads and the tumor, as well as the relationship between the tumor and the surrounding tissue.