Leiomyosarcoma (LMS) is a rare form of sarcomacancer arising from bones and/or soft tissue (cancera disease where abnormal cells split without control and spread to other nearby body tissue and/or organs arising from bone, connective tissuea group of cells that work together to perform a function and/or soft tissuetissue/the material that joins, holds up or surrounds inside body parts such as fat, muscle, ligaments and lining around joints) that develops in smooth muscle cellsthe basic structural and functional unit of all living things. It is most commonly found in the abdomenstomach, stomach area, belly or uterus; however it can also be found in the skin, bloodthe red bodily fluid that transports oxygen and other nutrients around the body vessels, or bones.
There are two kinds of muscle cells: smooth muscle cells and skeletal muscle cells. Smooth muscle cells are responsible for involuntary movement, and are found within organs, glands, and blood vessels. They aid in food digestion, pumping blood throughout the body, urine flow and pregnancy contractions. Cancer that originates from smooth muscles is called leiomyosarcoma (LMS). In contrast, skeletal muscle cells are responsible for voluntary movement, and are attached to the bones in the body. They enable movement by contracting and relaxing in response to voluntary messages sent by the brain. Cancer that originates in skeletal muscle cells is called rhabdomyosarcoma (RMS).
LMS is more common in women, and tends to be diagnosed over the age of 50. However, anyone can develop this disease.
Types of Leiomyosarcoma
There are several different types of LMS, which are classified by the location they develop in.
Leiomyosarcoma of Soft Tissue
LMS of soft tissue is the most common type of LMS. It is most commonly found in the retroperitoneuma space located behind the abdomen that contains many important bodily structures, such as the kidneys (a space located behind the abdomen that contains many important bodily structures, such as the kidneys) and the uterus, however it can also occur in the abdominal organs or in the extremities. This type of LMS is often aggressive, and may not have as good of a prognosisto predict how a disease/condition may progress and what the outcome might be as other LMS subtypes.
For more information on Leiomyosarcoma of the uterus, please refer to the Rare Cancers Australia Uterine Sarcoma page.
Leiomyosarcoma of Cutaneous Origin
LMS of cutaneous origin, also known as LMS of the skin, is a less common type of LMS that tends to develop in the middle layer of the skin (dermis). These tumours are thought to arise from pilar arrector muscles, which are tiny muscles attached to hair follicles in the skin that contract when we are cold in order to generate heat. Unlike other types of LMS, this subtype is slightly more common in men. While cutaneous LMS can be aggressive and metastasise, this type of tumoura tissue mass that forms from groups of unhealthy cells can have a good prognosis.
Leiomyosarcoma of Vascular Origin
LMS of vascular origin, also known as LMS of the blood vessels, is a very rare type of LMS. It is most likely to develop in larger veins, such as the inferior vena cava (carries deoxygenated blood from the lower parts of the body to the heart to become oxygenated) and pulmonary arteries (carry deoxygenated blood from the heart to the lungs to become oxygenated). In rare cases, it may also develop in the peripheral arteries (supply oxygenated blood from the heart to the rest of the body). Vascular LMS can be aggressive, and may not have as good of a prognosis as other types of LMS.
Leiomyosarcoma of the Bone
LMS of the bone is a very rare type of LMS that usually develops in the long bones of the body, such as the femur (thigh bone), humerus (upper arm bone), radius and ulna (forearm bones), and fibula and tibia (lower leg bones). Unlike most types of LMS, this type is more common in males. LMS of bone is often aggressive, and may not have as good of a prognosis as other types of LMS.
Treatment
If LMS is detected, it will be staged and graded based on size, metastasiswhen the cancer has spread to other parts of the body, also known as mets (whether the cancer has spread to other parts of the body) and how the cancer cells look under the microscope. Stagingthe process of determining how big the cancer is, where it started and if it has spread to other areas and grading helps your doctors determine the best treatment for you.
TNM Staging System
Cancers can be staged using the TNM staging system:
- T (tumour) indicates the size and depth of the tumour.
- N (nodes) indicates whether the cancer has spread to nearby lymph nodessmall bean-shaped structures that filters harmful substances from lymph fluid.
- M (metastasis) indicates whether the cancer has spread to other parts of the body.
This system can also be used in combination with a numerical value, from stage 0-IV:
- Stage 0: this stage describes cancer cells in the place of origin (or ‘in situ’) that have not spread to nearby tissue.
- Stage I: cancer cells have begun to spread to nearby tissue. It is not deeply embedded into nearby tissue and had not spread to lymph nodes. This stage is also known as early-stage cancer.
- Stage II: cancer cells have grown deeper into nearby tissue. Lymph nodes may or may not be affected. This is also known as localisedaffecting only one area of body cancer.
- Stage III: the cancer has become larger and has grown deeper into nearby tissue. Lymph nodes are generally affected at this stage. This is also known as localised cancer.
- Stage IV: the cancer has spread to other tissues and organs in the body. This is also known as advancedat a late stage, far along or metastatic cancer.
Cancers can also be graded based on the rate of growth and how likely they are to spread:
- Gradea description of how abnormal cancer cells and tissue look under a microscope when compared to healthy cells I: cancer cells present as slightly abnormal and are usually slow growing. This is also known as a low-grade tumour.
- Grade II: cancer cells present as abnormal and grow faster than grade-I tumours. This is also known as an intermediate-grade tumour.
- Grade III: cancer cells present as very abnormal and grow quickly. This is also known as a high-grade tumour.
FIGO Staging System
Gynaecological cancers, such as uterine LMS, can be staged using the Federation of Gynaecologythe study of the female reproductive system and related diseases and Obstetrics (FIGO) system from stage I to IV:
- Stage I: cancer cells are confined to the uterus only. This stage is also known as early-stage cancer.
- Stage II: cancer cells have grown deeper into nearby organs in the pelvis, such as the ovaries, fallopian tubes, bladdera hollow, muscular sac in the pelvis that stores urine and/or bowelportion of the digestive system that digests food (small bowel) and absorbs salts and water (large bowel); also called intestines. This is also known as localised cancer.
- Stage III: the cancer has become larger and has spread beyond the pelvis into the lining of the abdomen (peritoneumthe membrane that lines the abdominal cavity). Lymph nodes are also often affected. This is also known as advanced or metastatic cancer.
- Stage IV: the cancer has spread to more distant organs, such as the lungs or the liver. This is also known as advanced or metastatic cancer.
Treatment Options
Once your tumour has been staged and graded, your doctor may recommend genetic testinga procedure that analyses DNA to identify changes in genes, chromosomes and proteins, which can be used to analyse tumour DNA to help determine which treatment has the greatest chance of success, which analyses your tumour DNA and can help determine which treatment has the greatest chance of success. They will then discuss the most appropriate treatment option for you.
Treatment is dependent on several factors, including fertility (if tumour is in the uterus), type, stage of disease and overall health.
Treatment options for LMS may include:
- Surgerytreatment involving removal of cancerous tissue and/or tumours and a margin of healthy tissue around it to reduce recurrence to remove as much of the tumour as possible (varies based on location).
- Radiation therapya treatment that uses controlled doses of radiation to damage or kill cancer cells.
- Chemotherapya cancer treatment that uses drugs to kill or slow the growth of cancer cells, while minimising damage to healthy cells.
- Targeted therapymedication that targets specific molecular features of cancer cells.
- Clinical trialsresearch studies performed to test new treatments, tests or procedures and evaluate their effectiveness on various diseases.
- Palliative carea variety of practices and exercises used to provide pain relief and improve quality of life without curing the disease.
For more information on the treatment options, please refer to the Rare Cancers Australia Treatment Options page.
Treatment for Uterine LMS and Fertility
Treatment for uterine LMS may make it difficult to become pregnant. If fertility is important to you, discuss your options with your doctor and a fertility specialist prior to the commencement of treatment.
Risk factors
While the cause of LMS remains unknown, the following factors may increase the likelihood of developing the disease:
- Hereditary retinoblastoma
- Li-Fraumini syndrome.
- Neurofibromatosis type 1 (NF1).
- Tuberous sclerosis.
- Nevoid basal cell carcinomacancer arising from tissues that line organs syndrome.
- Gardner syndrome.
- Werner syndrome.
- Being immunocompromised.
Not everyone with these riskthe possibility that something bad will happen factors will develop the disease, and some people who have the disease may have none of these risk factors. See your general practitioner (GP) if you are concerned.
Symptoms
Symptoms of LMS often vary based on location.
General Symptoms of Leiomyosarcoma
General symptoms of LMS may include:
- Pain in affected area.
- Swelling.
- Massa growth of cells that come together to make a lump, may or may not be cancer in affected area.
- Fatiguea state of extreme tiredness or exhaustion, can be physical or mental.
- Fever.
- Unexplained weight loss and/or loss of appetite.
- Malaise (general feeling of unwell).
- Nauseato feel sick or likely to vomit and/or vomiting.
Symptoms of Gastrointestinal Leiomyosarcoma
In addition to the general symptoms listed above, patients with LMS in the gastrointestinal tract may experience:
- Changes in bowel habits, such as black and foul-smelling stools.
- Vomiting of blood.
- Abdominal discomfort.
Symptoms of Uterine Leiomyosarcoma
In addition to the general symptoms listed above, patients with LMS in the uterus may experience:
- Abnormal vaginal bleeding (not associated with menstruation).
- Abnormal vaginal discharge.
- Changes in bladder and/or bowel habits.
- Abdominal or pelvic pressure and/or pain.
Symptoms of Cutaneous Leiomyosarcoma
In addition to the general symptoms listed above, patients with LMS in the skin may experience:
- Pink, purple, brown, or red skin discolouration.
- Painful lesions on the skin.
- Crusting and/or ulceration of affected area.
- Itching.
- Burning.
- Bleeding.
Symptoms of Vascular Leiomyosarcoma
In addition to the general symptoms listed above, patients with LMS in blood vessels may experience:
- Hepatomegalyenlargement of the liver (enlargement of the liver).
- Jaundiceyellowing of the skin and the whites of the eyes (yellowing of the skin and/or the whites of the eyes).
- Ascitesa buildup of fluid in the abdomen (fluid build-up in the abdomen).
- Lower extremity oedemaswelling in parts of the body caused by a buildup of fluid, also known as fluid retention (swelling of the ankles, feet, and legs).
- Abdominal pain.
- Dyspnea (shortness of breath).
- Chest discomfort.
Symptoms of Leiomyosarcoma in the Bone
In addition to the general symptoms listed above, patients with LMS in bones may experience:
- Inconsistent pain in affected bone.
- Pain in affected bone that becomes worse at night.
- Easily broken bones.
- Numbness in affected area.
Not everyone with the symptoms above will have cancer, but see your general practitioner (GP) if you are concerned.
Diagnosis/diagnosing
If your doctor suspects you have a LMS, they may order the following tests to confirm the diagnosisthe process of identifying a disease based on signs and symptoms, patient history and medical test results and refer you to a specialist for treatment.
Physical examination
Your doctor will collect your overall medical history, as well as your current symptoms. Following this, they may examine your body to check for any abnormalities.
Imaging & blood tests
The doctor will take images of your body using magnetic resonance imagingtests that create detailed images of areas inside the body (MRI), a computed tomography scan (CT scan), and/or positron emission tomography (PET scan), depending on where it is suspected the cancer is. The doctor may also look at other parts of the body and looks for signs of metastasis. Additionally, a blood test may be taken to assess your overall health and help guide treatment decisions.
Biopsy
Once the location(s) of the cancer has been identified, the doctor will perform a biopsyremoval of a section of tissue to analyse for cancer cells to remove a section of tissue using a needle. The tissue sample will then be analysed for cancer cells. This can be done by a fine needle aspiration (FNA) or a core needle biopsy (CNB).
