This page was reviewed under our medical and editorial policy by
Maurie Markman, MD, President, Medicine & Science at CTCA.
This page was updated on September 12, 2022.
The staging guidelines developed by the American Joint Committee on Cancer (AJCC) are often used to stage bone cancers, and they allow doctors to communicate important information with each other in a standardized way.
Bone cancer stages are based on four categories:
T (tumor) describes the size of the original tumor.
N (node) indicates whether cancer is present in the lymph nodes.
M (metastasis) refers to whether cancer has spread to other parts of the body.
G (grade) describes the appearance of cancerous tissue and how much it resembles healthy tissue when studied under a microscope.
Bone cancers that contain many different cell types (like healthy tissue does) are considered low grade and generally are slow to grow and spread. Low-grade tumors may also be described as well differentiated.
High-grade bone cancer looks very abnormal compared with healthy tissue and tends to grow and spread more quickly. High-grade tumors may also be described as poorly differentiated.
The bone cancer grade may help your care team determine how quickly the cancer is likely to spread and how best to treat it. The grade influences your prognosis and the likelihood that the cancer will respond well to treatment. Low-grade tumors tend to have a better outlook, while high-grade tumors may be more difficult to treat.
There are four grades designated for bone cancer.
After the grade and TNM score are assigned, these measures are combined to determine the cancer’s overall stage.
Tumors are generally measured in centimeters. Eight centimeters is about 3 inches.
The cancer cells are still localized to the bone, and the tumor is considered low-grade. Stage 1 bone cancer is divided into two subcategories.
These cancers are still localized to the bone, but they’re considered high grade. Stage 2 bone cancer is divided into two subcategories:
Primary bone cancers at this stage are still localized to the bone, but they are high grade and have spread to several places within the same bone. These are multiple G2 or G3 high-grade tumors.
This is the most advanced form of the disease. In stage 4, the cancer has spread beyond the bone to other areas of the body. For bone cancer, staging also takes into account how abnormal the cells look under the microscope (the grade). Stage 4 bone cancer can be any T or N, meaning the tumor may be any size and may have grown into the lymph nodes. The cancer may be categorized as stage 4A or 4B.
Bone cancer may return after treatment concludes, which is called recurrent bone cancer. After treatment, people with bone cancer may receive follow-up care to check for any signs of recurrence.
With recurrent bone cancer, further testing is done to restage the cancer and determine where and how much it’s spread. The tests used to restage recurrent bone cancer usually resemble the tests used to diagnose and stage the original cancer.
Bone cancer survival rates vary from person to person and are impacted by factors such as whether the cancer has spread, the type of bone cancer and the patient’s overall health and response to treatment.
However, everyone’s personal experience is different. Talk to your care team about questions you have about your diagnosis and personal factors.
The survival rates for each bone cancer type are divided into three categories:
Distant bone cancer also refers to stage 4 bone cancer survival rate.
Here are the five-year survival rates for each type of bone cancer, according to the American Cancer Society: