Imaging is required to thoroughly evaluate bone lesions or soft tissue lumps and bumps for a potential sarcoma diagnosis. Results are evaluated by our experienced radiologists, who specialize in musculoskeletal imaging of bones, joints, and soft tissues.

The scans used depend on the type of sarcoma suspected. They include:

• Ultrasound: For soft tissues, ultrasound imaging can show the size, shape, and location of the suspected mass. It can also help tell if it’s a fluid-filled cyst or tumor. Ultrasound is not used for diagnosing bone sarcomas.
• X-rays: Though not effective for diagnosing soft tissue tumors, X-ray images can show our team if cancer started in a bone or spread there from elsewhere. X-rays can sometimes also help doctors tell the type of bone sarcoma present.
• Computed tomography (CT): By taking X-rays from many angles, our team can create a 3D image of the suspected tumor while measuring its size. CT scans can also determine if cancer has spread to other areas such as the lungs.
• Magnetic Resonance Imaging (MRI): Using magnetic fields instead of radiation, these scans help our team confirm a sarcoma diagnosis. They provide detailed information about the tumor and the tissues around it. They also help with treatment planning, including determining whether sarcoma surgery can remove the tumor.

Sometimes imaging is all we need to determine an accurate diagnosis, but in many cases, you may need further testing.

Unless imaging tests definitely rule out sarcoma, a biopsy should be performed before any treatment in order to confirm if the bone lesion or soft tissue lump or bump is a sarcoma, and which kind. We can also get a better sense of how quickly the cancer may grow and spread.

If we have your imaging studies in the Penn Medicine system, we can often offer a biopsy the same day as your consultation—an option not often available elsewhere. We then return at least preliminary results within a day or two.

Once we take a sample, one of our musculoskeletal pathologists studies the tissue under a microscope. Our pathologists see a high number of sarcomas each year, so they know exactly what to look for. Other sarcoma programs often come to our pathologists for guidance in reviewing their own tissue samples.

To stage bone sarcomas, we may recommend additional, specialized imaging. Bone sarcoma staging includes four main stages, with additional sub-stages:

• Stage IA: The tumor is smaller (8 centimeters or less) and the cancer has not spread. The tissue should look fairly close to healthy tissue, meaning grade 1, or low grade.
• Stage IB: As with stage IA, cancer has not spread and tumor tissue appears fairly normal when it can be graded. However, the tumor is larger (greater than 8 centimeters) or there is more than one tumor present.
• Stage IIA: Cancer still has not spread, but the tumor is a higher grade (grade 2 or 3). At this stage, it’s still 8 centimeters or smaller.
• Stage IIB: Like stage IIA, tumors are either grade 2 or 3 and the cancer has not spread. The tumor is bigger than 8 centimeters.
• Stage III: While the cancer has not spread, the bone has developed more than one high-grade tumor.
• Stage IVA: Cancer has spread to the lungs.
• Stage IVB: Cancer has spread to other locations, such as lymph nodes or other bones or organs.

Soft tissue sarcomas in the legs and retroperitoneum (back part of the belly) are divided into four main stages and several sub-stages:

• Stage IA: The tumor is still small (5 centimeters or less) and the cancer has not spread. The tumor’s tissue looks fairly close to healthy tissue, and is grade 1 or low grade.
• Stage IB: The tumor is larger than 5 centimeters but the cancer has not spread and tumor tissue appears fairly normal.
• Stage II: Cancer still has not spread. However, tumor tissue is high grade, and looks different than healthy tissue. It may differ by a modest amount (grade 2) or by a lot (grade 3). Stage II tumors are 5 centimeters or less.
• Stage IIIA: Like stage II, the tumor is either grade 2 or 3 and cancer has not spread. The tumor is larger–between 5 and 10 centimeters.
• Stage IIIB: The tumor has grown beyond 10 centimeters and is either grade 2 or 3, and the cancer has not spread.
• Stage IV: The cancer has spread, to nearby lymph nodes or places farther away in the body.

When evaluating treatment options, we also consider the tumor’s depth because deeper tumors often require more extensive treatment than shallower tumors.