Uterine sarcoma
Encyclopedia
A uterine sarcoma is a malignant tumor that arises from the smooth muscle
or connective tissue
of the uterus
.
s, endometrial stromal sarcoma
s, carcinosarcoma
s and "other" sarcomas.
cancer staging
system.
is a screening test for cervical cancer
and not designed to detect uterine sarcoma.
, CAT scan, MRI) and, if possible, obtaining a tissue diagnosis by biopsy
, hysteroscopy
, or D&C
.
Ultimately the diagnosis is established by the histologic examination of the specimen. Typically malignant lesions have >10 mitosis
per high power field. In contrast a uterine leiomyoma as a benign lesion would have < 5 mitosis per high power field.
Surgery
is the mainstay of therapy if feasible involving total abdominal hysterectomy
with bilateral salpingo-oophorectomy. Other approaches include radiation therapy
, chemotherapy
, and hormonal therapy.
Prognosis is relatively poor.
- only about 4% will be uterine sarcomas. Generally, the cause of the lesion is not known, however patients with a history of pelvic radiation are at higher risk. Most tumors occur after menopause
.
Women who take long-term tamoxifen
are at higher risk.
Smooth muscle
Smooth muscle is an involuntary non-striated muscle. It is divided into two sub-groups; the single-unit and multiunit smooth muscle. Within single-unit smooth muscle tissues, the autonomic nervous system innervates a single cell within a sheet or bundle and the action potential is propagated by...
or connective tissue
Connective tissue
"Connective tissue" is a fibrous tissue. It is one of the four traditional classes of tissues . Connective Tissue is found throughout the body.In fact the whole framework of the skeleton and the different specialized connective tissues from the crown of the head to the toes determine the form of...
of the uterus
Uterus
The uterus or womb is a major female hormone-responsive reproductive sex organ of most mammals including humans. One end, the cervix, opens into the vagina, while the other is connected to one or both fallopian tubes, depending on the species...
.
Histology
Subtypes include leiomyosarcomaLeiomyosarcoma
Leiomyosarcoma , aka LMS, is a malignant cancer of smooth muscle....
s, endometrial stromal sarcoma
Endometrial stromal sarcoma
Endometrial stromal sarcoma is a rare endometrial tumor arising from the stroma of the endometrium rather than the glands. There are three grades for endometrial stromal tumors, as follows...
s, carcinosarcoma
Carcinosarcoma
Carcinosarcoma is a malignant tumor that is a mixture of carcinoma and sarcoma ....
s and "other" sarcomas.
- If the lesion originates from the stroma of the uterine lining it is an endometrial stromal sarcoma.
- If the uterine muscleMuscleMuscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...
cell is the originator the tumor is a uterine leiomyosarcoma. - Carcinosarcomas comprise both malignant epithelial and malignant sarcomatous components.
Classification
Uterine sarcoma is staged like endometrial carcinoma at time of surgery using the FIGOInternational Federation of Gynecology and Obstetrics
The International Federation of Gynaecology and Obstetrics, usually just FIGO as the acronym of its French name Fédération Internationale de Gynécologie et d'Obstétrique, is a worldwide NGO organisation representing obstetricians and gynaecologists in over one hundred territories...
cancer staging
Cancer staging
The stage of a cancer is a description of the extent the cancer has spread. The stage often takes into account the size of a tumor, how deeply it has penetrated, whether it has invaded adjacent organs, how many lymph nodes it has metastasized to , and whether it has spread to distant organs...
system.
- Stage IA: tumor is limited to the endometrium
- Stage IB: invasion of less than half the myometriumMyometriumThe myometrium is the middle layer of the uterine wall, consisting mainly of uterine smooth muscle cells , but also of supporting stromal and vascular tissue...
- Stage IC: invasion of more than half the myometrium
- Stage IIA: endocervical glandular involvement only
- Stage IIB: cervical stromal invasion
- Stage IIIA: tumor invades serosa or adnexa, or malignant peritoneal cytology
- Stage IIIB: vaginal metastasis
- Stage IIIC: metastasis to pelvic or para-aortic lymph nodes
- Stage IVA: invasion of the bladder or bowel
- Stage IVB: distant metastasis, including intraabdominal or inguinal lymph nodes
Signs and Symptoms
Unusual or postmenopausal bleeding may be a sign of a malignancy including uterine sarcoma and needs to be investigated. Other signs include pelvic pain, pressure, and unusual discharge. A nonpregnant uterus that enlarges quickly is suspicious. However, none of the signs are specific. Specific screening test have not been developed; a Pap smearPap smear
The Papanicolaou test is a screening test used in to detect pre-cancerous and cancerous processes in the endocervical canal of the female reproductive system. Changes can be treated, thus preventing cervical cancer...
is a screening test for cervical cancer
Cervical cancer
Cervical cancer is malignant neoplasm of the cervix uteri or cervical area. One of the most common symptoms is abnormal vaginal bleeding, but in some cases there may be no obvious symptoms until the cancer is in its advanced stages...
and not designed to detect uterine sarcoma.
Diagnosis
Investigations by the physician include imaging (ultrasoundUltrasound
Ultrasound is cyclic sound pressure with a frequency greater than the upper limit of human hearing. Ultrasound is thus not separated from "normal" sound based on differences in physical properties, only the fact that humans cannot hear it. Although this limit varies from person to person, it is...
, CAT scan, MRI) and, if possible, obtaining a tissue diagnosis by biopsy
Biopsy
A biopsy is a medical test involving sampling of cells or tissues for examination. It is the medical removal of tissue from a living subject to determine the presence or extent of a disease. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically...
, hysteroscopy
Hysteroscopy
Hysteroscopy is the inspection of the uterine cavity by endoscopy with access through the cervix. It allows for the diagnosis of intrauterine pathology and serves as a method for surgical intervention .-Method:...
, or D&C
Dilation and curettage
Dilation and curettage refers to the dilation of the cervix and surgical removal of part of the lining of the uterus and/or contents of the uterus by scraping and scooping . It is a diagnostic gynecological procedure.D&C normally is referred to a procedure involving a curette, also called sharp...
.
Ultimately the diagnosis is established by the histologic examination of the specimen. Typically malignant lesions have >10 mitosis
Mitosis
Mitosis is the process by which a eukaryotic cell separates the chromosomes in its cell nucleus into two identical sets, in two separate nuclei. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membrane into two cells containing roughly...
per high power field. In contrast a uterine leiomyoma as a benign lesion would have < 5 mitosis per high power field.
Management
Therapy is based on staging and patient condition and utilizes one or more of the following approaches.Surgery
Surgery
Surgery is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, or to help improve bodily function or appearance.An act of performing surgery may be called a surgical...
is the mainstay of therapy if feasible involving total abdominal hysterectomy
Hysterectomy
A hysterectomy is the surgical removal of the uterus, usually performed by a gynecologist. Hysterectomy may be total or partial...
with bilateral salpingo-oophorectomy. Other approaches include radiation therapy
Radiation therapy
Radiation therapy , radiation oncology, or radiotherapy , sometimes abbreviated to XRT or DXT, is the medical use of ionizing radiation, generally as part of cancer treatment to control malignant cells.Radiation therapy is commonly applied to the cancerous tumor because of its ability to control...
, chemotherapy
Chemotherapy
Chemotherapy is the treatment of cancer with an antineoplastic drug or with a combination of such drugs into a standardized treatment regimen....
, and hormonal therapy.
Prognosis is relatively poor.
Epidemiology
The vast majority of malignancies of the uterine body are endometrial carcinomasEndometrial cancer
Endometrial cancer refers to several types of malignancies that arise from the endometrium, or lining, of the uterus. Endometrial cancers are the most common gynecologic cancers in the United States, with over 35,000 women diagnosed each year. The incidence is on a slow rise secondary to the...
- only about 4% will be uterine sarcomas. Generally, the cause of the lesion is not known, however patients with a history of pelvic radiation are at higher risk. Most tumors occur after menopause
Menopause
Menopause is a term used to describe the permanent cessation of the primary functions of the human ovaries: the ripening and release of ova and the release of hormones that cause both the creation of the uterine lining and the subsequent shedding of the uterine lining...
.
Women who take long-term tamoxifen
Tamoxifen
Tamoxifen is an antagonist of the estrogen receptor in breast tissue via its active metabolite, hydroxytamoxifen. In other tissues such as the endometrium, it behaves as an agonist, hence tamoxifen may be characterized as a mixed agonist/antagonist...
are at higher risk.