Ob-Gyn questions? Ask a gynecologist online.
I am assuming that you have a moderate risk mass or a simple oophorectomy (removal of the ovary) would not be planned. You do not give any info about the size of the mass or the CA125 level. If this is a moderate risk mass, the risk of cancer is 20 % You should be having the surgery in a cancer center with a gyn oncologist. Not with a regular ob gyn Dr.
This is low risk due to the size and negative ca 125 Risk of cancer is 3-20 percent. Unfortunately this is the protocol. It would be better though if a gyn oncologist could operate. Thats not going to happen, but at least it seems that your regular gyn is just planning to take out the ovary and refer you if its malignant. I doubt it will be and good luck.
No Its not hyperplasia. Or anything close. It is disordered uterine lining due to hormone imbalance. Please consider a positive rating. Thanks