2014 Volume 66 Issue 1 Pages 43-49
We report a case with a recurrent right ovarian mature cystic teratoma which showed malignant transformation to squamous cell carcinoma (SCC) after laparoscopic enucleation of a right ovarian tumor. A 34-year-old patient, para 0, visited our hospital for evaluation of a mass 11 cm in diameter in the right ovary. The blood test findings were as follows : carbohydrate antigen (CA) 19-9, 904 U/ml; CA125, 29 U/ml; and SCC antigen, 2.8 ng/ml. Magnetic resonance imaging (MRI) showed no evidence of malignancy, and laparoscopic enucleation of a right ovarian tumor (pathological diagnosis of mature cystic teratoma) was performed. Nine months after this operation, she visited our department with a right ovarian tumor and ascites. Transvaginal sonography revealed a solid tumor 8 cm in diameter, and the serum SCC antigen level was 30.5 ng/ml. MRI showed a solid tumor 8 cm in diameter in the right ovary with enlarged pelvic lymph nodes. Fluorine-18-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (CT) also showed FDG uptake not only at the tumor site (maximum standardized uptake value, 15.9) but also in the para-aortic lymph nodes suggestive of metastases. Contrast-enhanced CT also revealed an enlarged lymph node in the left supraclavicular fossa. The patient was diagnosed with stage IV ovarian cancer and underwent surgery. The tumor was present in the right adnexa, which had infiltrated the posterior lobe of the broad ligament of the uterus. The surgery was completed with excision of the right adnexa, biopsy of pelvic lymph nodes, omentectomy, and intraperitoneal administration of carboplatin. The final diagnosis was SCC of the ovary with only inflammatory changes in the biopsied lymph nodes (pT2bN0M0). There was a possibility that the lymph node in the supraclavicular fossa might also show inflammatory changes. Although radical surgery after biopsy was also suggested to the patient, she refused. Nine courses of chemotherapy with paclitaxel and carboplatin (TC therapy) were performed, and her clinical course has been uneventful without recurrence for 20 months to date since the second surgery. To our knowledge, there are no prior case reports describing metachronous malignant transformation to SCC after the enucleation of a mature cystic teratoma, as in our present case. Moreover, treatment was difficult due to the multiple suspected metastases to the lymph nodes in this case ; however, she has followed a favorable course thus far. Though extremely rare when the pathological diagnosis was benign tumor at the time of ovary-preserving surgery in young patients, we should keep in mind the possibility of recurrence as malignant transformation when treating patients with risk factors for malignant transformation. [Adv Obstet Gynecol, 66 (1) : 43-49, 2014 (H26.2)]
