LAUSR

OBJECTIVE Endometriosis is an estrogen-dependent chronic disease, which is regarded as a disease of reproductive-aged women. Endometriosis is most frequently diagnosed during reproductive period. We aimed to determine the frequency of endometrioma in women over 40 years of age who were operated for adnexial mass. MATERIALS AND METHODS A total of 1100 women over 40 years of age underwent surgery for adnexal mass were included in this cohort study between 2006 and 2016. Women who met the criteria were compared regarding the type of adnexial mass, age groups, menopausal status and malignant transformation. RESULTS A total of 299 women (27.2%) with benign ovarian mass were determined to have endometrioma. Women with endometrioma were younger and nulliparous more frequently comparing women without endometrioma. Although 20% of the patients in the endometrioma group were postmenopausal, 70% of the patients in the control group were postmenopausal. Endometrioma-associated ovarian tumors were developed in nearly 11% of women with endometrioma. CONCLUSIONS Even though endometriosis is accepted as a disease of reproductive-aged women, it can occur over 40 years of age. Detailed anamnesis and careful gynecological examination provide key information for differential diagnosis. Accurate information about the risk of malignant transformation should be informed.