A synovial sarcoma can be hard or soft to touch and become large enough to produce pain, numbness, and restrict motion.
Synovial sarcoma in the early stages looks like a painless, harmless, and immovable mass or lump (a swollen spot). Initially, it may resemble common conditions, such as a cyst (fluid-filled mass) or a lipoma (fatty lump).
The tumor can be hard or soft to touch, grows gradually, and may become large enough to produce symptoms, such as pain, restricted motion, and numbness (due to pressure on the nerves, muscles, or blood vessels).
The term synovial sarcoma is defined as:
- Synovial: Comes from the name “synovium,” a connective tissue that lines the inside of the joints.
- Sarcoma: Presence of cancer cells in bone and soft tissues including cartilage, fat, muscle, blood vessels, and fibrous tissues.
What is synovial sarcoma?
Synovial sarcoma is a rare type of soft tissue (cells that connect, support, and surround the bones and other organs) sarcoma that can arise anywhere in the body but most commonly develops in the extremities, particularly in the thighs, knees, feet, and forearms and, sometimes, the head and neck or abdomen.
Each year, it affects only one to three individuals in a million people (estimated to be less than one percent of all the diagnosed cancers).
It can affect people of all age groups, with a higher tendency to affect teenagers and young adults, and men more often than women.
Other types of soft tissue sarcoma
- Leiomyosarcoma, occurs in muscles
- Liposarcoma, occurs in fat tissues
- Angiosarcoma, develops in the blood or lymph glands
- Gastrointestinal stromal tumors, occur in the connective tissues
What are the symptoms of synovial sarcoma?
In the early stages, there may be no noticeable symptoms, but as the tumor grows, symptoms may vary depending on the tumor location, size, and spread to other sites.
- A painless lump or a mass
- Swelling under the skin, cannot be moved and increases in size over time
- Difficulty swallowing and shortness of breath (if the head and neck region or lungs are affected)
- Abdominal pain, the feeling of fullness, and constipation (develops in the abdomen)
What causes synovial sarcoma?
There are no proven or well-established causative factors known for this disease. However, the disease is known to be associated with a chromosomal translocation of chromosome 18 and chromosome X.
This translocation leads to a mutation of the gene, which, in turn, leads to abnormal and uncontrolled growth of the cells forming a tumor, a contributing factor in the development of this disease.
The risk of developing synovial sarcoma is increased in people who have:
- Been exposed to chemicals, such as thorium dioxide, vinyl chloride, or arsenic
- Undergone radiation therapy
- Had a previous history of long-term swelling in the arms or legs
- Inherited conditions, such as Li Fraumeni syndrome or neurofibromatosis type I
How is synovial sarcoma diagnosed?
Synovial sarcoma is a high-grade tumor that can metastasize and spread to distant parts of the body (almost 50 percent of cases), the lungs being the most common and the first site of metastasis.
- X-rays: Images of soft tissues are taken for analysis.
- Computed tomography scan: To determine the extent of the tumor.
- Magnetic resonance imaging: To determine the extent of adjacent tissue involvement.
- Biopsy: A sample of the tumor is removed for further analysis.
- Open biopsy: Sample is removed by a surgical incision.
- Core needle biopsy: Sample is taken by using a large needle.
- Positron emission tomography scan: To identify possible metastasis.
How is synovial sarcoma treated?
The risk of developing distant metastases is higher for patients with tumors larger than 5 cm.
Treatment is planned by considering factors, such as:
- Size of the tumor
- Location of the tumor
- How invasive the tumor is
- Is the tumor metastasize at the time of diagnosis
- Are lymph nodes involved
The treatment plan may consist of:
- Surgery: Entire tumor removal along with some of the surrounding healthy tissues to make sure all the cancerous cells are removed. In rare cases, amputation of the affected limb is the only option left.
- Chemotherapy: Doxorubicin and ifosfamide might be recommended, especially in advanced or metastatic disease.
- Radiation: High-powered energy rays are used to shrink the tumor; they can be used before, during, and after the surgical removal of the tumor.
- Targeted therapy: Involves drugs that block substances necessary for cancer cell growth.
Skin Cancer Symptoms, Types, Images
Medically Reviewed on 2/1/2022
Image Source: iStock Images
DerSarkissian C. What is Synovial Sarcoma. WebMD. https://www.webmd.com/cancer/synovial-sarcoma-overview
National Institutes of Health. Synovial Sarcoma. https://www.cancer.gov/pediatric-adult-rare-tumor/rare-tumors/rare-soft-tissue-tumors/synovial-sarcoma
Genetic and Rare Diseases Information Center. Synovial Sarcoma. https://rarediseases.info.nih.gov/diseases/7721/synovial-sarcoma
Cleveland Clinic. Synovial Sarcoma. https://my.clevelandclinic.org/health/diseases/22012-synovial-sarcoma