What did they say about your sister's ovarian tumors? Did the Doctor mention a biopsy of the ovarian tumors, because that is only way to be certain if it is cancer or not. Does she have any of the symptoms of ovarian cancer? The endometiral biopsy is being done because she has had frequent periods. That can be the start of menopause or diagnostic of a problem in the uterus. Did the Dr. do any blood work? a CA-125? You need more information, next week when you go with your sister ask the questions. You and your sister can write down what you want to know, it helps when you are nervous. If cancer is mentioned, you want to go to a GYN-Oncologist, they specialize in women's cancer, and are best trained to operate if it is cancer. In the mean time you could write to the physician forum on ovarian cancer, she answers on the weekend. Good luck to your sister, the majority of ovarian tumors, cysts are benign.
They are doing a biopsy on the masses she has no symptoms of ovarian cancer just getting her period every 20 days. The doctor said she does not know what it is that is why they are doing the biopsy.