Uterine Adenosarcoma, from the CureRays guide library.

Uterine adenosarcoma is a rare cancer of the uterus made of a benign glandular part and a cancerous connective-tissue part; most behave gently, but a feature called sarcomatous overgrowth makes them far more dangerous.

What it is.

Uterine adenosarcoma is an uncommon cancer of the uterus that is a 'mixed' tumor — it contains benign-looking glands (the 'adeno' part) woven together with a low-grade cancerous connective tissue (the 'sarcoma' part). It often grows as a polyp-like mass inside the uterine cavity and may show up as abnormal bleeding, a mass protruding through the cervix, or pelvic pain, in women across a wide age range. Most adenosarcomas are low-grade and have a good outlook. The crucial exception is 'sarcomatous overgrowth,' meaning more than a quarter of the tumor is pure high-grade sarcoma — this, along with deep growth into the muscle of the uterine wall, sharply raises the risk of recurrence and spread. Surgery is the main treatment, and pathology determines who needs more.

How radiation treats it.

Radiation damages the DNA inside cancer cells so they can no longer divide. After surgery for a higher-risk adenosarcoma, pelvic radiation or vaginal brachytherapy targets the areas most likely to harbor leftover cells — the pelvis and the top of the vagina — to lower the chance the cancer returns there. Brachytherapy delivers its dose from inside the body, concentrating it exactly where it is needed and sparing nearby organs. Treatment is painless, given over a series of short sessions, and leaves no radioactivity in the body afterward.

The ways we can treat it.

Pelvic external-beam radiation (IMRT/IGRT). Image-guided, intensity-modulated radiation treats the pelvis when there is a higher risk of local return, shaping the dose around the bladder, bowel, and rectum to limit side effects.

Vaginal brachytherapy. A radiation source is placed inside the vagina for a short time to deliver a concentrated dose to the top of the vagina — a common site of recurrence — while sparing surrounding organs.

Stereotactic body radiation (SBRT). Delivers a few high, focused doses to an isolated recurrence or metastasis when surgery is not the best choice.

Questions we hear often.

What is 'sarcomatous overgrowth' and why does it matter so much? It means that more than a quarter of the tumor is made of pure, high-grade sarcoma rather than the usual gentler mix. It is the most important predictor of how an adenosarcoma will behave — tumors with it are far more likely to come back or spread, so your team may recommend radiation or chemotherapy in addition to surgery.

Will I need anything besides surgery? Many women with early, low-risk adenosarcoma are cured by hysterectomy alone. Added radiation or chemotherapy is considered when the pathology shows sarcomatous overgrowth, deep invasion of the uterine muscle, or spread beyond the uterus.

Can my ovaries be preserved? It depends on your age, the tumor's features, and your wishes. Removing the ovaries is common, especially after menopause, but preservation is sometimes discussed for younger women with early, low-risk tumors. This is an individual decision to make with your gynecologic oncologist.

This guide is informational only. It is not medical advice — please confirm anything here with your care team.