Giant struma ovarii with pseudo-Meigs’syndrome and raised cancer antigen-125 levels: A case report

BACKGROUND: Struma ovarii is a type of monodermal mature teratoma composed entirely or mainly of thyroid tissue, accounting for 1% to 3% of all ovarian teratomas and 0.3% to 1.0% of all ovarian tumors. Of which, struma ovarii with ascites and pleural effusion, called pseudo-Meigs’syndrome and raised cancer antigen-125 levels (CA 125) is even rarer. CASE SUMMARY: This paper reports the diagnosis and treatment of a patient of struma ovarii with pseudo-Meigs’syndrome, presenting with the clinical features of ovarian carcinoma: Complex pelvic mass, gross ascites, right pleural effusion and markedly elevated serum CA 125 levels. During the operation, a cystic-solid mass about 20 cm × 10 cm × 5 cm in the right adnexa and a solid mass with the size of 3 cm × 2 cm × 0.1 cm in the left ovary were observed. She underwent right adnexectomy and resection of the left ovarian mass and histopathology revealed a mature left-sided ovarian teratoma and struma ovarii of right adnexal mass. During 1-year follow-up, the patient recovered well, tumor markers and other indicators returned to normal. CONCLUSION: The diagnosis and treatment process of this case suggests that the clinical symptoms of struma ovarii with pseudo-Meigs’syndrome are lack specificity, which is easily misdiagnosed. Clinicians should improve the understanding of this disease, enhance the awareness of early screening, and improve the level of diagnosis and treatment.