Hi, I understand your concern. It would help me to know the size of the cyst in serial ultrasounds and your menopausal status as well as any family history of cancer. Your issues about the CA 125 test and BRCA test. The CA125 is a substance that is increased in many females having ovarian cancer. Sometimes it is increased in women with normal ovaries and in other conditions like liver tumors etc. So elevated levels make us think in term of malignancy but normal levels do not mean that there is no malignancy. In other words it is not a 100% guarantee that the tumor is malignant or not. If BRCA is positive it means that the person is more predisposed to malignancy or has higher chance of having a cancer. But again it does not mean that cancer is there. You must have understood by now that these tests help us but are not 100% sure of predicting a cancer. Hence other issues like age and menopause are important in addition to these test. Another finding that you mentioned is that the cyst is complex. This increases the chances of it being malignant, but agin not a 100% true finding in every case. The ovaries do continue to function after menopause but to a very low level. Also, if one ovary is removed the other can be kept [provided the tumor is not cancerous] and you can still enjoy the benefits. The issue of keeping or removing the ovaries arises in women that are undergoing a hysterectomy for reasons other than ovaries like fibroid uterus etc. In these cases preservation of ovaries is desirable, but if ovaries themselves are diseased, there is no question of keeping them. I suggest that you discuss these with your doctor and have a CA125 and BRCA done. If they are positive it is better to remove the ovary [or at least the cyst] as the cyst is a complex one. Hope I was able to help you. Thanks for using Health Care Magic. I would be happy to answer any further queries. Have a nice day. Dr. Madhuri Bagde Consultant Obstetrician and Gynecologist