Learn about the different stages of soft tissue sarcoma, a type of rare cancer.
When you’re diagnosed with soft tissue sarcoma, your medical team will want to find out if the cancer has spread (and if so, how much) using a process called staging. Staging helps doctors know how serious the soft tissue sarcoma diagnosis is and how to best treat it. Here’s more information on soft tissue sarcoma treatment options.
How Soft Tissue Sarcoma Is Staged
“Soft tissue sarcoma is staged based on tumor size, whether or not it’s spread to lymph nodes, and whether or not it has metastasized to a site different than its site of origin,” says Richard Bakst, MD, a radiation oncologist at Mount Sinai Hospital.
The staging system that most doctors use for soft tissue sarcoma is called the American Joint Committee on Cancer (AJCC) TNM system, which helps doctors learn more details about the patient’s condition. The TNM system is based on four key pieces of information:
- (T) Tumor: How large is the cancer?
- (N) Lymph nodes: Has it spread to the lymph nodes?
- (M) Metastasis: Has it spread to nearby organs?
- (G) Grade: How much do the sarcoma cells look like cancer cells?
Tumor (T) Stage
“T stage refers to size, and it’s typically broken up into 5 centimeter intervals, and it’s staged T1 to T4,” says Dr. Bakst.
- T1: 5 cm or less
- T2: 5 to 10 cm
- T3: 10 to 15 cm
- T4: 15 cm or more
Lymph Nodes (N) Stage
“N stage refers to whether or not it’s spread to lymph nodes,” says Dr. Bakst.
- N0: Hasn’t spread to lymph nodes
- N1: Has spread to lymph nodes
Metastasis (M) Stage
“[M stage means] either it has metastasized to another site or it hasn’t,” says Dr. Bakst.
- M0: has not spread to distant sites
- M1: has spread to distant sites
“The 4th component is grade, and that is determined by how the pathologist describes the cancer under the microscope,” says Dr. Bakst.
- G1: cells appear almost normal and aren’t particularly aggressive
- G2: cells appear moderately abnormal and are semi aggressive
- G3: cells appear clearly abnormal and are very aggressive
After Soft Tissue Sarcoma Staging: Next Steps
“So in general we try to get all patients to surgery to have the mass excised,” says Dr. Bakst. After surgery, doctors will then reassess the size of the tumor, and whether or not it has spread to the lymph nodes. “[This] determines whether or not they need radiation. And there we look at the grade, and whether the surgeon got it all out,” says Dr. Bakst.
“In general, for tumors that are bigger than 5 centimeters and are intermediate to high grade, we tend to give radiation after. We’re looking at those variables from surgery to understand what the next step is,” says Dr. Bakst.
Soft Tissue Sarcoma Staging and Your Prognosis
Stages are also used to help understand a patient’s survival rate. Doctors often use the five-year survival rate, which is a percentage of patients who live for at least five years after they’ve been diagnosed with cancer. This rate is often based on previous outcomes of large numbers of people who have had the disease, but they can’t predict every case because every patient’s cancer is different. And of course, many patients live much longer than five years or are cured completely.
The overall relative five-year survival rate of people with soft tissue sarcomas is around 50% according to the National Cancer Institute (NCI), but the NCI does not use the AJCC system. The NCI groups sarcomas by whether they haven’t spread from the site of origin (called localized), have spread to nearby lymph nodes or tissues (called regional), or have spread to distant sites away from the main tumor (called distant). A patient’s outlook depends on many factors, but according to the NCI system, the five-year survival rates look like this:
- 83% for localized sarcomas
- 54% for regional stage sarcomas
- 16% for sarcomas with distant spread
Soft Tissue Sarcoma Stages. American Cancer Society. (Accessed on March 7, 2018 at https://www.cancer.org/cancer/soft-tissue-sarcoma/detection-diagnosis-staging/staging.html)
Survival by Stage of Soft Tissue Sarcoma. American Cancer Society. (Accessed on March 7, 2018 at https://www.cancer.org/cancer/soft-tissue-sarcoma/detection-diagnosis-staging/survival-rates.html)