Background Adnexal masses detected in breast cancer survivors are of particular concern because of the increased risk of ovarian malignancy. Aims This study was performed to analyse adnexal masses among women with breast cancer with regard to variables predictive of malignancy. Methods The study included women with breast cancer who had undergone surgery for an adnexal mass between 2002 and 2010 at Hacettepe University Hospital. A total of 45 consecutive women with a mean age of 47.3years (range 2576) were analysed retrospectively. Results Of 45 cases reviewed, benign ovarian pathology was found in 35 cases (77.8%) and malignant ovarian neoplasms were found in 10 cases (22.2%). A simple ovarian cyst was observed in 25 cases (71.4%) as the most common type of benign pathology. Of the 10 cases with malignancy, 5 (50%) had primary ovarian carcinoma, while the remaining five women had breast carcinoma metastases to the ovary. Complex mass at ultrasonography, increased CA 125 level and oestrogen receptornegative tumour were found to be the significant predictors of ovarian malignancy. Conclusions Although an adnexal mass in a woman with breast cancer is most commonly a benign ovarian cyst, the overall risk of ovarian malignancy is increased with breast cancer. An adnexal mass with complex architecture detected by ultrasonography and high CA 125 level were the strongest risk factors associated with increased risk of malignancy.