Leiomyosarcoma (LMS) is a rare type of malignant (cancerous) tumor
Leiomyosarcoma (LMS) is a rare type of malignant (cancerous) tumor that arises from the smooth muscle cells. Smooth muscle cells are the muscle cells of the internal organs and blood vessels that are not controlled consciously. LMS is classified as a soft tissue sarcoma and can arise in any part of the body, the most common site being the abdomen.
LMS is resistant cancer that is generally less responsive to chemotherapy or radiation. If LMS is identified early and removed by surgery while still small and have not spread locally, the outlook is good. If LMS is large or has spread to other parts of the body, the treatment becomes more difficult, and the prognosis is not very good. Most forms of LMS are aggressive tumors that may spread to other areas of the body potentially causing life-threatening complications.
LMS has a high risk of recurrence, and patients must examine themselves routinely after the treatment. In about 50% of the patients, it recurs within 8-16 months of the initial diagnosis and treatment. Sometimes, they remain dormant for long periods and recur after a few years.
Where does leiomyosarcoma occur?
Leiomyosarcoma (LMS) can appear in the blood vessels, heart, liver, pancreas, bladder, gastrointestinal system, retroperitoneum (the space behind the abdominal cavity), uterus, and skin.
It is most commonly found in the uterus, stomach, intestines, and retroperitoneum.
- Uterine LMS forms in the smooth muscle layer of the uterus.
- Gastrointestinal LMS might originate from the smooth muscles in the gastrointestinal tract or from a blood vessel.
- Cutaneous LMS arises from the piloerector muscles in the skin.
- Other primary sites are in the abdomen, intestines, truncal and abdominal organs, blood vessels, etc. LMS arises from the smooth muscle layer of the blood vessel known as tunica media.
What causes leiomyosarcoma?
The exact cause of leiomyosarcoma (LMS) is unknown. Malignant tumors may develop due to abnormal changes in oncogenes or tumor suppressor genes. Genetic changes in deoxyribonucleic acid (DNA), which are the carriers of genetic code, cause cellular malignant changes. Genetic changes may occur either spontaneously due to unknown reasons or may be inherited. Certain inherited conditions that may increase the risk of LMS include:
- Gardner syndrome
- Li-Fraumeni syndrome
- Werner syndrome
- Neurofibromatosis type 1
- Hereditary retinoblastoma
- Tuberous sclerosis
- Nevoid basal cell carcinoma syndrome
- Immune deficiency syndromes
What are the signs and symptoms of leiomyosarcoma?
Symptoms may vary from patient to patient and depend upon the location, size, and progression of the tumor. A patient with leiomyosarcoma (LMS) in the early stages may not have any obvious symptoms (asymptomatic). When the tumor gets, larger symptoms appear.
Signs and symptoms of LMS include:
- Fatigue, fever, and weight loss
- Malaise (general feeling of ill health)
- Nausea and vomiting
- Pain may occur but is uncommon
- Lump under the skin
- Change in bladder or bowel habits
- Melena (black, tarry, foul-smelling stools)
- Hematemesis (vomiting of blood)
- Abdominal discomforts
- Abnormal vaginal discharge or bleeding (in uterine LMS)
How is leiomyosarcoma treated
Treatment may vary for each patient and depends on the size, location, extent of tumor, metastasis to distant sites, patient’s age, and general health. Treatment may include:
- Surgery: The best option for LMS treatment is the surgical removal of the entire tumor and any affected tissues. If some cancer cells remain, there are chances of cancer arising in site or in a different part of the body.
- Radiation therapy: It may be used before surgery to reduce the size of a tumor. Radiation may also be used after the surgical removal of the tumor to prevent it from growing back.
- Chemotherapy (anti-cancer drugs): When the leiomyosarcoma (LMS) tumor is large or if the cancer cells have spread to other parts of the body, then chemotherapy is used in combination with surgery and radiation therapy to treat patients.