Got a funny-looking bump or lump somewhere on your body? If so, it's best to get it checked out because it might be a sarcoma, said Dr. Vincent Y. Ng, an assistant professor of orthopaedics at the University of Maryland School of Medicine. Sarcomas are cancerous tumors that are often missed by doctors, said Ng, also co-director of the bone, cancer and soft tissue sarcoma service at the University of Maryland Greenebaum Comprehensive Cancer Center. Ng said only a specialist can really determine if a sarcoma is present.
What are sarcomas?
Sarcomas are a category of rare, malignant (cancerous) tumors that originate from connective tissues, such as bone, muscle, fat or cartilage. There are about 14,000 new cases of sarcoma per year in the United States. About 1 in 23,000 people per year will be diagnosed with sarcoma. About 1 in 300 people will be affected by sarcoma at some point in their life, and 1 in 1,000 families will have a child affected by sarcoma. Sarcomas arise either in the "soft tissue" (flesh) or in the bone. Unlike other types of cancer that can spread to the bone, such as breast, prostate or kidney cancer, sarcomas typically are from the bone or soft tissue itself.
How is it diagnosed?
Many sarcomas are overlooked by patients or misdiagnosed by physicians who are not familiar with the tumors. Any abnormal lump, bump or mass should be evaluated by a specialist, typically an orthopedic oncologist. If the sarcoma occurs in the abdominal or chest region, a general surgeon or thoracic surgeon is appropriate. It is important to note the following features about sarcomas:
•Sarcomas may be painful OR painless. Do not assume it is not worrisome just because it does not hurt.
•Sarcomas may be very slow growing or very rapidly growing.
•Sarcomas can occur in adults or children.
•Sarcomas can occur anywhere in the body, even in your fingers.
•Sarcomas can be right under the skin or deep within the body.
•Sarcomas may be very firm or relatively soft.
•Sarcomas can be very large (the size of a football) or very small (the size of a grape).
Do not assume a lump is simply a fatty tumor, muscle strain, or bruise. It can easily be a sarcoma or other malignant tumor. Delaying your diagnosis of a sarcoma may allow it to grow or spread to other parts of your body.
After seeing a specialist, imaging such as an X-ray, MRI or CT scan is typically performed. A biopsy may be necessary to make the diagnosis of sarcoma. It is crucial that the biopsy is performed by a surgeon or radiologist who is experienced in treating sarcomas. A poorly performed biopsy can jeopardize the ability to later remove the tumor.
What are the risk factors?
Most patients who develop sarcoma do not have identifiable risk factors. Some rare genetic abnormalities or mutations can contribute to the incidence of sarcoma. Prior exposure to high levels of radiation can increase the risk of certain types of sarcoma. Some benign tumors can turn into sarcomas over time.
What are the symptoms?
Oftentimes, sarcomas do not have any symptoms. This is why many soft tissue sarcomas are not diagnosed right away. In comparison, bone sarcomas are often painful. If you have a lump or bump, you should have it examined by a specialist.
How is it treated?
Treatment of almost all sarcomas will typically require surgical removal of the tumor. It is very important to remove the entire tumor. Even if a small portion of the sarcoma is left behind, there is a high probability that it will recur. Only surgeons who are specialized in the treatment of sarcomas should perform surgical resection of the tumor. After the tumor is removed, reconstructive surgery may be necessary to replace missing bone or soft tissues in order to optimize function. Amputation is rarely necessary for sarcoma and a skilled surgeon will usually be able to preserve your limb.
Radiation is used to help treat many types of sarcoma. While radiation alone typically is not sufficient to completely kill the tumor, it can sterilize some of the surrounding area to make it easier to surgically remove. There are different forms of radiation including photons and protons and different ways of delivering the radiation. An experienced radiation oncologist will help maximize destruction of the tumor and minimize damage to normal tissue.
Chemotherapy may be necessary to treat microscopic tumor cells that may have spread from the original tumor to other parts of the body. Preventing or treating these "metastases" is the key to surviving sarcoma. Not all sarcomas, however, are responsive to chemotherapy. New antibodies and targeted molecular therapy drugs are currently being tested for sarcomas that do not respond to traditional chemotherapy.
The University of Maryland Bone and Soft Tissue Sarcoma Service is starting a first-in-the-nation clinical trial that pairs immunotherapy for high-risk soft tissue sarcomas with the current standard of care. The current odds of survival from high-risk soft tissue sarcoma are approximately 50 percent. Our goal with immunotherapy is to improve those odds. The rationale behind the trial is to jump start the patient's immune system to help clear any microscopic deposits of soft tissue sarcoma. The science behind the trial is that cancer suppresses the body's natural immune system which allows it to grow and spread throughout the body essentially unchecked. Radiation "exposes" the cancer and allows the immune system to recognize the cancer as a dangerous entity. Immunotherapy revs up the immune system to seek and destroy cells that are recognized as cancerous.
What are the chances of survival?
The chances of survival from sarcoma vary widely depending on the type of sarcoma. Whether or not it has spread and is detectable in other parts of the body is the most important determinant of survival. Other factors that affect prognosis are aggressiveness, size and location. Generally, younger and healthier patients tend to do better than more elderly and frail patients. Receiving treatment by a highly specialized sarcoma team will ensure that patients have the best chance at survival.