Leiomyosarcoma is a rare form of cancer (malignant) tumor that develops in smooth muscle cells. While it can develop nearly anywhere inside the body like the intestines, liver, skin, pancreas, and blood vessels, it usually arises in the uterus, pelvis, or abdomen, especially in the gastrointestinal system or bladder. Often referred to as soft tissue sarcoma, this disease involves involuntary and voluntary muscle groups and can be defined as a malignant cancer to differentiate this condition from leiomyoma, a benign form of the disease. When diagnosed in its initial stages, leiomyosarcoma is considered treatable.
Usually, the most effective treatment of leiomyosarcoma is surgical removal of the affected area or organ. To ensure that the cancer has been fully removed from the body, the doctor will usually excise (cut out) healthy surrounding tissue to minimize the potential risk of a new tumor growing at the same location. Nearly fifty percent of all patients who have been treated or cured of leiomyosarcoma must undergo additional treatments within the first eight months or so after the initial diagnosis.
- What Causes Leiomyosarcoma?
- Who Is at Risk for Leiomyosarcoma?
- Common Symptoms
- Diagnosing Leiomyosarcoma
- Leiomyosarcoma Treatment Options
What Causes Leiomyosarcoma?
Doctors, scientists, and researchers have yet to determine the actual cause of leiomyosarcoma. It might develop because of a genetic mutation that allows abnormal cells to grow out of control and eventually form tumor masses. If so, the genetic mutation likely occurs on its own or through a genetic predisposition meaning it is inherited from a parent.
Doctors know that soft tissue sarcoma can develop in areas that were previously treated using radiation therapy to cure or manage another form of cancer. However, the development of leiomyosarcoma usually does not happen until at least a decade after the final radiotherapy treatment. Exposure to chemicals is also thought to be a factor in the development of leiomyosarcoma.
Who Is at Risk for Leiomyosarcoma?
Individuals with the highest risk of developing leiomyosarcoma include those who:
- Are over 50 years of age
- Have previously received radiation treatments to cure or manage another form of cancer
- Been exposed to specific chemicals including weed killers, vinyl chloride (in the production of plastic), and dioxins used to manufacture paper and pesticides
Both men and women appear to be equally at risk for developing soft tissue leiomyosarcoma. Statistics maintained by the American Cancer Society reveal that approximately 15,000 new cases of leiomyosarcoma are diagnosed every year in the United States which account for approximately one percent of all cancers that affect adults.
Some studies have shown that women who have undergone gynecological surgical procedures involving a power morcellator to remove a tumor or diseased organ/tissue might be at higher risk of developing leiomyosarcoma. This is because power morcellation has been proven to spread cancers cells including leiomyosarcoma throughout the pelvic area during the procedure. This allows the cancer to spread and affect other areas and organs in the abdominal cavity that include the abdominal wall, intestines, bladder, kidneys, and liver.
Research has revealed that cancer cells spread by a power morcellator during a gynecological procedure have the potential of entering the bloodstream and lymphatic system and move throughout the body to affect the brain, heart, lungs, and/or bones.
In the initial stages of development of the disease, many individuals never notice or experience any symptoms. However, the most common leiomyosarcoma symptoms include:
- A swollen area or lump
- Swollen or painful areas on the body
- Abdominal bloating and/or discomfort
- Vaginal bleeding in postmenopausal women or a notable change in menstrual periods in women who are pre-menopausal
- Vaginal discharge
- Urinating more often than normal
- Black-colored stools
- Melena (foul-smelling stools)
- Hematemesis (blood in vomit)
- Stomach aches
Any individual who experiences any of the symptoms should consider talking to their doctor about a diagnosis that might or might not involve the disease.
Usually, an accurate diagnosis verified by a competent doctor or pathologist will be based on a comprehensive patient medical history and a thorough physical examination that includes test results. It might also involve surgical removal of a tissue biopsy for an under the microscope examination along with MRI, CT and PET scans that generate visual imaging of the affected area to identify an undetectable painful mass or lump. The doctor might also recommend:
- Fine Needle Aspiration – Using a long thin needle inserted through the skin into a nodule or cancerous mass, the doctor can aspirate (obtain) a tissue sample that can be examined under a microscope.
- Incisional Biopsy – The doctor can make an incision into the affected area and surgically withdraw a small tissue sample for microscopic examination to determine its histopathology (biological makeup).
- Hysteroscopy – This test can diagnose leiomyosarcoma-associated issues that occur in the womb. This often involves a biopsy, or a tissue sample was taken and examined under a microscope. This test is often performed in an outpatient environment using a local anesthetic. However, some women require or prefer general anesthesia to minimize discomfort.
- Laboratory Tests – Certain laboratory tests using conjunction with MRI or CT imaging can determine any possible infiltration of leiomyosarcoma into regional lymph nodes and determine if it has metastasized (spread) to other areas of the body.
Through laboratory tests, biopsies, and a physical examination, the doctor may be able to determine the histological features of the different forms of leiomyosarcoma subtypes that could include:
- Myxoid Leiomyosarcoma
- Epithelioid Leiomyosarcoma
- Granular Cell Leiomyosarcoma
- Inflammatory Leiomyosarcoma
- Dedifferentiated Leiomyosarcoma
This rare disease often requires a team of medical experts in a specialized hospital or medical setting to plan and provide the best treatment. The desired treatment for the disease will depend on numerous factors including the patient's overall health, the position in size of the tumor in the body, and its progression that was likely staged during when the condition was first diagnosed. The most common available treatments to cure or manage leiomyosarcoma include:
- Surgery – Locally controlling soft tissue sarcoma is often highly successful after a surgical resection where the affected part is cut away from the body. Usually, preoperative planning must be performed before the surgery is conducted to ensure that surgical margins are well defined where removing enough healthy tissue surrounding the affected area can prevent local recurrence of the disease.
- Radiotherapy – Radiation therapy is highly effective when treating tumors or vital structures that are adjacent to the cancerous area. Radiotherapy is important because it can improve the rate of controlling leiomyosarcoma and be used as a palliative measure when extensive metastasis has already developed in the advanced stages of the disease.
- Chemotherapy – Doctors typically recommend chemotherapy to treat metastatic diseases including advanced age leiomyosarcoma. While this treatment does not provide a cure, it can slow down the progression of the disease and help improve survival rates. In addition, it is often used postoperatively to shrink a tumor that could not be successfully removed during a surgical procedure.
If the above treatments have failed, individuals can participate in clinical trials if they meet basic criteria. However, participating in a clinical trial requires an application by the treating doctor and approval by an ethics committee that protects the integrity of the test and the interests of the patient.