Uterine sarcoma is a rare cancer of the uterus (womb). It is not the same as endometrial cancer, a much more common cancer that starts in the lining of the uterus. Uterine sarcoma most often starts in the muscle underneath that lining. The most common symptom of uterine sarcoma is bleeding after menopause. Let your health care provider know as soon as you can about:

Any bleeding that is not part of your menstrual period
Any bleeding that happens after menopause 

Most likely, the bleeding will not be from cancer. But you should always tell your provider about unusual bleeding.

Other possible symptoms of uterine sarcoma include:
Vaginal discharge that does not get better with antibiotics and may occur without bleeding
A mass or lump in the vagina or uterus
Having to urinate often 

Some of the symptoms of uterine sarcoma are similar to those of fibroids. The only way to tell the difference between sarcoma and fibroids is with tests, such as a biopsy of tissue taken from the uterus.