How Synovial Sarcoma Is Diagnosed

Table of Contents
View All
Table of Contents

Synovial sarcoma can grow for a long time before a person is aware that something is wrong.

As a result, the approach to diagnosing this condition is made through a physical examination and various imaging tests, such as a computed tomography (CT) scan or an X-ray.

Doctors may also perform a biopsy, removing a sample of the tumor to be examined to determine if it contains cancerous cells.

This article will detail the specific tests doctors use to effectively diagnose Synovial sarcoma.

Synovial Sarcoma Diagnosis

Verywell / Theresa Chiechi


The earliest sign of synovial sarcoma is often a lump or swelling that seemingly comes out of nowhere. However, on average, this type of tumor has been present for two years before diagnosis. These lumps often occur in the arms, legs, or feet.

Synovial sarcoma may or may not be painful, depending on the location of the tumor. If the cancer presses on nearby nerves, it can be extremely painful. You might also have numbness and tingling sensations if a nerve is affected.

Because synovial sarcoma frequently grows in the arms and legs, another early sign of this condition can be difficulty moving the affected joint.

Decreased range of motion can be a sign of many other medical conditions, including arthritis. However, some forms of arthritis cause stiffness that may come and go. Joint issues caused by synovial sarcoma will stay the same or get worse. Undergoing imaging tests can help rule out conditions like arthritis and bursitis.

Age of Diagnosis

One-third of patients diagnosed with synovial sarcoma are under the age of 30. Joint issues occurring in teenagers and young adults should be assessed by a doctor—particularly when not caused by a recent injury.

Physical Examination

Physical examination for synovial sarcoma begins with the doctor asking questions about your symptoms and your medical history.

The doctor will palpate, or touch, the affected area to get an idea of the shape, size, firmness, and general location of the tumor. The doctor will also move the affected joint to assess your range of motion.

Labs and Tests

There are no specific blood tests for the diagnosis of synovial sarcoma. However, your doctor might include blood work in your initial examination to rule out other causes of your symptoms, such as infection.

A definitive diagnosis of cancer typically requires a biopsy. This procedure is usually performed after imaging tests suggest that the tumor may be cancerous. A biopsy can be performed with fine needle aspiration, in which a thin, hollow needle is inserted into the tumor and a small sample of cell tissue is removed.

In some cases, an endoscopic biopsy is performed by making a small incision in the skin and removing a piece of the tumor. In either case, the tissue is then examined under a microscope.

Genetic Testing

Synovial sarcoma can sometimes be diagnosed through genetic testing. In some people who have this condition, a gene translocation—or rearrangement of the chromosomes—occurs which causes the X chromosome and chromosome 18 to fuse together. This can occur in both females and males with synovial sarcoma.


Imaging types used to assess and monitor synovial sarcoma include:

  • Radiographs, or X-rays, provide the doctor with images of bones and joints. Even though X-rays are not required to make the diagnosis of synovial sarcoma, they are often performed as a first step in determining why a patient has pain or decreased movement in a joint. Doctors can also see if the sarcoma has caused any changes to the bones around the tumor.
  • Ultrasound, a test that produces images using sound waves, might also be performed to help determine if a lump is fluid-filled (like a cyst) or solid (like a tumor).
  • Computed tomography scans, or CT scans, also help diagnose synovial sarcoma. CT scans are a more powerful type of X-ray that produces 3D images of the affected area. CT scans help the doctor determine if the tumor has spread to other nearby organs.
  • Magnetic resonance imaging, or MRI, provides more detailed information about the exact size and location of synovial sarcoma.
  • Positron emission tomography, or PET scan, uses radioactive sugar to aid in the diagnosis of cancer. This type of testing is useful to determine whether cancer has spread to other parts of the body.

Staging Synovial Sarcoma

Once a diagnosis of synovial sarcoma is made, the next step is staging—a process that determines how much cancer is in the body. Stages of synovial sarcoma range from one to four, with four being the most severe.

There are multiple systems that are used to stage cancer and ultimately determine the best treatment. However, the American Joint Committee on Cancer (AJCC) TNM system is most commonly used. This system is based on four factors:

  • The size and extent of the tumor
  • Whether the cancer is present in nearby lymph nodes
  • Whether the cancer has metastasized, or spread, to distant areas of the body
  • The grade of the tumor, which predicts how quickly the tumor will grow and spread

Differential Diagnosis

Please remember that lumps and bumps can be caused by a variety of factors, including a recent injury, benign (not harmful) tumors, a hematoma (a collection of blood outside a vessel), an abscess (a collection of pus), or even a mass of fat. Confirming a diagnosis with your doctor can help you determine your next steps—and give you peace of mind.

A Word From Verywell

It can take a while for symptoms of synovial sarcoma to be noticed. See your doctor if you have pain, joint stiffness, or notice a lump or swelling, particularly if you haven't had a recent injury. While these symptoms can be caused by different, less-serious conditions than cancer, early detection improves overall outcomes.

If you have been diagnosed with synovial sarcoma, consider joining a support group to help you cope with your condition.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Cancer Institute. Synovial Sarcoma.

  2. Gazendam AM, Popovic S, Munir S, Parasu N, Wilson D, Ghert M. Synovial sarcoma: a clinical review. Curr Oncol. 2021;28(3):1909-1920. Doi:10.3390%2Fcurroncol28030177

  3. American Cancer Society. Types of biopsies used to look for cancer.

  4. Nakano K, Takahashi S. Translocation-related sarcomas. Int J Mol Sci. 2018;19(12):3784. doi:10.3390%2Fijms19123784

  5. American Cancer Society. Soft tissue sarcoma stages.

By Aubrey Bailey, PT, DPT, CHT
Aubrey Bailey is a physical therapist and professor of anatomy and physiology with over a decade of experience providing in-person and online education for medical personnel and the general public, specializing in the areas of orthopedic injury, neurologic diseases, developmental disorders, and healthy living.