Malign Transformation in the Mature Cystic Teratoma of the Ovary: Presentation of 9 Case Studies

Abstract

A AB BS S TTR RA AC CT T O Ob bj je ec ct ti iv ve e: : Mature cystic teratoma (MCT) is the most frequently observed ovarian germ cell tumor. It constitutes up to 10-20% of the ovarian tumors. The incidence rate of malign transformation in ovarian mature cystic teratoma is approximately 2%. Clinical presentation of malignant MCT depends on the extension and histological type of the secondary malignancy. Squamous cell carcinoma is the most common secondary tumor seen in malignantly-transformed MCT cases. The prognosis of patients with malignant transformation in teratoma is very poor and most patients die within 1 year. However, the prognosis is better if the tumor is limited to one ovary, with an intact capsule not adhered to adjacent structure and with a uniform thickness of the cyst wall. In this study, the incidence, histologic types, and prognosis of the malign transformed MCT were assessed. M Ma at te er ri ia al l a an nd d M Me et th ho od ds s: : Six hundred seventy-six cases were diagnosed as mature cystic teratoma of the ovary between January 2000 and December 2010 in our Pathology Laboratory, Tepecik Obstetrics and Gynecology Hospital. Malignant transformation was determined in 9 of these patients (1.48%) of whom operative data, histopathologic findings, and postoperative follow-up data were evaluated in light of the literature. R Re es su ul lt ts s: : Out of 676 mature cystic teratoma cases, malignant transformation was determined in nine of them (1.48%). Six out of nine patients were in the postmenopausal period while two were in perimenopausal period and one was premenopausal period. Median age was found to be 45.7 (34-71 years). The average diameter of the ovarian tumor was 9.5 (7-15) cm. The tumor settled on the left in five cases, whereas it settled on the right in four cases. Squamous cell carcinoma was found in three cases, mucinous cystadenocarcinoma was found in two cases, thyroid papillary carcinoma was found in two cases, carcinoid tumor was found in one case and signet ring cell carcinoma was found in one case. According to surgical FIGO staging, four cases were classified as stage IA, three cases were classified as stage IC, one case was classified as stage II B and one case was classified as stage II C. Average follow-up period was 71 months (5-126 months). C Co on nc cl lu us si io on n: : In cases preliminary diagnosed as mature cystic teratoma, malign transformation possibility should be considered especially in women in postmenopausal period and in those with large-size tumors. Frozen section examination plays an important role in identifying both the method of surgical treatment and the patient prognosis. K Ke ey y W Wo or rd ds s: : Ovarian neoplasms; teratoma; carcinoma; cell transformation, neoplastic Ö ÖZ ZE ET T A Am ma aç ç: : Matür kistik teratom (MKT) en sık görülen ovarian germ hücreli tümördür. Over tümörlerinin %10-20 kadarını oluşturur. Overin matür kistik teratomlarının malign transformasyon insidensi yaklaşık %2 civarındadır. Malign değişim gösteren MKT'nin klinikte ...