What r the chances that my large cantaloupe size fibroid on my uters will be cancerous?

Very Very small: The FDA estimates the chance of a fibroid being cancer (at the time of a myomectomy or hysterectomy for a benign fibroid) to be about 1 in 350. That is still very very low odds.

Leiomyosarcoma: The rate of leiomyosarcomas (cancerous fibroid) is around 1 in 20,000. The media has made it sound much much more common. The size of fibroid is less of an issue than how rapidly it enlarged. A CA-125 may be of use even though it is more associated with ovarian cancer and an MRI may help with your situation. However, if done with having children, I would consider a simple hysterectomy.

Consult your OBGYMD: Surgical removal of that large fibroid can give you peace of mind, although fibroids are benign uterine lesions there is always a possibility of cancerous changes

No one knows for: sure. Usually fibroids dont turn cancerous, but it is not possible to guess on the basis of symptoms. Fibroids cause pain and heavy periods and make people weak sometimes. Go see your OB GYN and if they feel then your fibroid need to come out and with your uterus also. So if your symptoms are not bad, dont worry about cancer and that it out when appropriate.

VERY SLIM!: Less than one in a thousand. MANY women have fibroids--any they usually are no problem. SOMETIMES thy are the cause of heavy periods, but unless they are blocking kidneys, or pressing on your bladder etc, you can just watch them. If there are worrisome findngs such as central "rotting", sudden increase in growth -not well defined), your doctor may advise surgery.