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Spotting the red flags of synovial sarcoma can make all the difference.


Synovial Sarcoma—What It Is and How to Detect It

Defining Sarcoma

Sarcomas are a large but rare group of cancers that start in the connective tissue of the body. Connective tissue is a body tissue that supports, protects, and gives structure to other tissues and organs in the body. Examples of connective tissue include bone and cartilage.

By definition, the word “sarcoma” means a tumor that is malignant (cancerous). The many types of sarcomas are defined based on where the tumors form in the body, be it bone or soft tissue.

Soft tissue sarcomas can form in fat, muscle, nerves, fibrous tissues, blood vessels, or deep skin tissues. They can develop in any part of the body; most commonly in the arms and legs.

About Synovial Sarcoma

Synovial sarcoma is a rare and aggressive form of soft tissue sarcoma that most commonly occurs near the joints. The term "synovial sarcoma" can be misleading, as these lesions do not originate from intra-articular synovium—the connective tissue lining the joints.

Although these tumors can occur anywhere in the body, they most commonly arise next to the knee joint. The tumors may also be located near the ankles, wrists, shoulders, and hips.

The first physical sign of synovial sarcoma may be a lump

Synovial sarcoma may evolve slowly with a high incidence of late metastasis, which is the spread of cancer to a different part of the body. Metastasis can occur in up to 50% of all synovial sarcoma cases.

Synovial Sarcoma—A Rare Disease

Synovial Sarcoma Is a Rare Type of Sarcoma

Synovial sarcoma accounts for ~5-10% of soft tissue sarcomas.

In a retrospective review of synovial sarcoma cases:

Synovial sarcoma more commonly occurs in young adults, ≤30 years of age.

Like many soft tissue sarcomas, the regional or remote spread of synovial sarcoma is known to be associated with poor prognosis.

Signs and Symptoms of Synovial Sarcoma

The majority of synovial sarcomas grow slowly, and symptoms usually last up to 2 years before diagnosis. Before swelling or the formation of a lump, patients may have pain or joint stiffening.

Given the insidious onset, younger age at presentation, and atypical symptoms, patients may initially be misdiagnosed with non-cancerous conditions, including myositis, synovitis, bursitis, or tendonitis.



Numbness and/or pain

How Synovial Sarcoma Is Diagnosed

Before starting therapy, all patients should be evaluated by a multidisciplinary team of sarcoma experts. After the history intake and physical examination, imaging—usually magnetic resonance imaging (MRI)—of the tumor is indicated. A biopsy and resection should then be carried out by an experienced sarcoma pathologist.

Methods that help diagnose synovial sarcoma include:

Regular X-rays may identify synovial sarcoma if large areas of the tumor are marked or outlined by calcifications. However, many synovial sarcomas don't show up on X-rays.

Computerized tomography (CT) scans are often useful in determining the extent of the tumor, including the severity and the size.

MRIs can show the degree to which the tumor is affecting nearby soft tissue, such as blood vessels and nerves.

If a tumor is detected, your doctor will need to review a sample of the tumor.

A procedure called a biopsy will be performed wherein a sample of the tumor will be removed. The sample is studied under a microscope to establish the presence of cancer and to determine the best treatment option.

If you think you may have synovial sarcoma, contact your healthcare provider.

Contacting your healthcare provider at the first sign of symptoms is important for finding the best method of tumor detection and receiving the correct diagnosis.

What Synovial Sarcoma Treatment Looks Like Today

Surgery to remove the tumor with the addition of radiotherapy and/or chemotherapy is currently the best practice in synovial sarcoma treatment.

The goal of surgery is to remove the full tumor along with a small amount of healthy tissue around it. In certain cases, this could mean the removal of an entire muscle or muscle group.

Synovial sarcoma treatment may also include radiotherapy or chemotherapy to further decrease the chances of recurrence.

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