By Dr. Herbert Loong for Cancer.net
What are sarcomas?
Sarcomas are a group of rare diseases that develop in the body’s muscle, bone, nerves, cartilage, tendons, blood vessels, and fatty and fibrous tissues. There are more than 70 different subtypes. They can affect almost any part of the body, inside or outside, but are most common in the arms, legs, and trunk (torso). Sarcomas are uncommon adults. But they make up 15% of all childhood cancers (0–14 years) and 11% of all cancers diagnosed in teenagers and young adults (15–24 years).
What are the main groups of sarcomas?
Bone sarcomas account for 0.2% of all new cancer cases in adults, making it a very rare form of cancer. There are under 3,500 new cases per year in the United States. Not all bone cancers are sarcomas.
Soft-tissue sarcomas account for 1% of all new cancer cases in adults. These sarcomas can affect any part of the body, developing in supporting or connective tissue such as the muscle, nerves, fatty tissue, and blood vessels. Soft-tissue sarcomas include:
Gastrointestinal stromal tumor (GIST). A GIST develops in the gastrointestinal tract, or digestive system, which includes the stomach and intestines.
Gynecological sarcomas. These sarcomas occur in the female reproductive system, which includes the uterus (womb), ovaries, vagina, vulva, and fallopian tubes. They can affect women of any age.
Retroperitoneal sarcomas. These sarcomas occur in the retroperitoneum. This is an area deep in the abdomen and pelvis, behind the abdominal lining (called the peritoneum), where organs such as the major blood vessels, kidneys, pancreas, and bladder are located.
How should sarcomas be treated?
Because sarcomas are rare and different parts of the body can be involved, it’s vital to take a multidisciplinary team (MDT) approach toward treatment. This means that a group of different types of doctors will work together to create a patient’s overall treatment plan. All people who are newly diagnosed should be referred to a cancer center that has experience treating sarcomas.
MDT discussions often start with a review of the tumor tissue that was used to make the sarcoma diagnosis. A pathologist, a doctor who specializes in interpreting laboratory tests, will look at the tissue sample again to ensure that the diagnosis is accurate. This is important because the decision on what sort of treatment to give depends on what type of disease a person has.
The MDT will also discuss the best sequence of different treatments, such as surgery, radiation therapy, or chemotherapy, to create a personalized treatment plan for the individual. The MDT will continue to follow the progress of a patient and, together, make important and time-sensitive treatment decisions.
Cancer centers with sarcoma MDTs are also more likely to have access to clinical trials that may provide different treatment options.
Are we making progress in treating sarcomas?
Over the last 2 decades, we’ve made significant strides in understanding sarcoma. Our knowledge of the molecular biology of this unique group of diseases allows us to better classify and group them. By understanding that sarcoma is not just 1 disease, but a large collection of distinct diseases, each with differing biologies, we’ve made significant treatment advances. They include new chemotherapies as well as targeted drugs for different sarcoma subtypes.
How we administer radiation therapy during sarcoma treatment has also improved in recent years. We’re able to provide it in a more focused manner, which reduces the risks of short- and long-term side effects. Surgery continues to be the most important treatment for many sarcomas. However, our improved understanding of how to best sequence chemotherapy and radiation therapy, and how to identify those who’ll most likely benefit from specific types of treatment, has been the cornerstone of recent success.
Where can I get more information or support?
Although sarcomas are rare diseases, it’s important for patients to know that they’re not alone. There are numerous local and national patient advocacy groups dedicated to increasing the awareness and knowledge of sarcomas among patients and their caregivers, and to providing support. You can find pages on Cancer.Net that list support organizations for soft-tissue sarcoma, Kaposi sarcoma, sarcoma of specific organs, bone cancer, and GIST.