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Definition of uterine sarcoma:
A rare type of uterine cancer that forms in muscle or other tissues of the uterus (the small, hollow, pear-shaped organ in a woman's pelvis in which a fetus develops). It usually occurs after menopause. The two main types are leiomyosarcoma (cancer that begins in smooth muscle cells) and endometrial stromal sarcoma (cancer that begins in connective tissue cells).
Uterine sarcoma is a disease in which malignant (cancer) cells form in the muscles of the uterus or other tissues that support the uterus.
The uterus is part of the female reproductive system. The uterus is the hollow, pear-shaped organ in the pelvis, where a fetus grows. The cervix is at the lower, narrow end of the uterus, and leads to the vagina.
Anatomy of the female reproductive system. The organs in the female reproductive system include the uterus, ovaries, fallopian tubes, cervix, and vagina. The uterus has a muscular outer layer called the myometrium and an inner lining called the endometrium.
Uterine sarcoma is a very rare kind of cancer that forms in the uterine muscles or in tissues that support the uterus. (Information about other types of sarcomas can be found in the summary on Soft Tissue Sarcoma in the A-Z List of Cancers.) Uterine sarcoma is different from cancer of the endometrium, a disease in which cancer cells start growing inside the lining of the uterus. (See the summary on Endometrial Cancer in the A-Z List of Cancers for information).
Being exposed to x-rays can increase the risk of uterine sarcoma.
Anything that increases your risk of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn’t mean that you will not get cancer. Talk with your doctor if you think you may be at risk. Risk factors for uterine sarcoma include the following:
- Past treatment with radiation therapy to the pelvis.
- Treatment with tamoxifen for breast cancer. If you are taking this drug, have a pelvic exam every year and report any vaginal bleeding (other than menstrual bleeding) as soon as possible.
Signs of uterine sarcoma include abnormal bleeding.
Abnormal bleeding from the vagina and other signs and symptoms may be caused by uterine sarcoma or by other conditions. Check with your doctor if you have any of the following:
- Bleeding that is not part of menstrual periods.
- Bleeding after menopause.
- A mass in the vagina.
- Pain or a feeling of fullness in the abdomen.
- Frequent urination.
Uterine Carcinosarcoma /Malignant mixed mullerian tumours (MMTs)
Carcinosarcoma of the uterus (also known as malignant mixed Mullerian tumour, MMT) is an extremely rare and highly aggressive subtype of uterine cancer.
MMT constitutes only 3-4% of uterine malignancies overall yet accounts for a disproportionate percentage of mortality, with five year survival rates ranging from 5-40%.
It is a biphasic (two-component) tumour containing a mixture of:
- Carcinoma: cancer showing epithelial differentiation
- Sarcoma: cancer showing mesenchymal differentiation
In the majority of uterine carcinosarcoma, both the carcinoma and the sarcoma components are histologically high grade (high grade cancer cells tend to grow and spread more quickly than low-grade cells).
It is not certain whether uterine carcinosarcoma starts out as carcinoma that undergoes sarcomatous transformation or as sarcoma that undergoes epithelial differentiation.
These tumours are most commonly found in the endometrium, however, they can arise in any organ of the female genital tract including:
- Fallopian tube
Clinically, patients with uterine MMT present with abnormal vaginal bleeding or pelvic or abdominal pain
MMTs are most often found in post-menopausal women, however rare cases have been found in younger women.
Tests that examine the uterus are used to detect (find) and diagnose uterine sarcoma.
The following tests and procedures may be used:
- Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.
- Pelvic exam: An exam of the vagina, cervix, uterus, fallopian tubes, ovaries, and rectum. The doctor or nurse inserts one or two lubricated, gloved fingers of one hand into the vagina and the other hand is placed over the lower abdomen to feel the size, shape, and position of the uterus and ovaries. A speculum is also inserted into the vagina and the doctor or nurse looks at the vagina and cervix for signs of disease. A Pap test or Pap smear of the cervix is usually done. The doctor or nurse also inserts a lubricated, gloved finger into the rectum to feel for lumps or abnormal areas.
Pelvic exam. A doctor or nurse inserts one or two lubricated, gloved fingers of one hand into the vagina and presses on the lower abdomen with the other hand. This is done to feel the size, shape, and position of the uterus and ovaries. The vagina, cervix, fallopian tubes, and rectum are also checked.
- Pap test: A procedure to collect cells from the surface of the cervix and vagina. A piece of cotton, a brush, or a small wooden stick is used to gently scrape cells from the cervix and vagina. The cells are viewed under a microscope to find out if they are abnormal. This procedure is also called a Pap smear. Because uterine sarcoma begins inside the uterus, this cancer may not show up on the Pap test.
Pap test. A speculum is inserted into the vagina to widen it. Then, a brush is inserted into the vagina to collect cells from the cervix. The cells are checked under a microscope for signs of disease.
- Transvaginal ultrasound exam: A procedure used to examine the vagina, uterus, fallopian tubes, and bladder. An ultrasound transducer (probe) is inserted into the vagina and used to bounce high-energy sound waves (ultrasound) off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. The doctor can identify tumors by looking at the sonogram.
Transvaginal ultrasound. An ultrasound probe connected to a computer is inserted into the vagina and is gently moved to show different organs. The probe bounces sound waves off internal organs and tissues to make echoes that form a sonogram (computer picture).
- Dilatation and curettage: A procedure to remove samples of tissue from the inner lining of the uterus. The cervix is dilated and a curette (spoon-shaped instrument) is inserted into the uterus to remove tissue. The tissue samples are checked under a microscope for signs of disease. This procedure is also called a D&C.
Dilatation and curettage (D and C). A speculum is inserted into the vagina to widen it in order to look at the cervix (first panel). A dilator is used to widen the cervix (middle panel). A curette is put through the cervix into the uterus to scrape out abnormal tissue (last panel).
- Endometrial biopsy: The removal of tissue from the endometrium (inner lining of the uterus) by inserting a thin, flexible tube through the cervix and into the uterus. The tube is used to gently scrape a small amount of tissue from the endometrium and then remove the tissue samples. A pathologist views the tissue under a microscope to look for cancer cells.
Certain factors affect prognosis (chance of recovery) and treatment options.
The prognosis (chance of recovery) and treatment options depend on the following:
- The stage of the cancer.
- The type and size of the tumor.
- The patient's general health.
- Whether the cancer has just been diagnosed or has recurred (come back).
For more information on Uterine Sarcoma click here
This link is to the National Cancer Institute (NCI) cancer website in the United States. There may be references to drugs and clinical trials that are not available here in Australia.
Information has also been sourced from sarcomahelp.org
For information about clinical trials that are available in Australia click here