Stages
Cancer stages are important tools to measure the extent and severity of cancer. It also estimates how far it has reached and if other organs are taken by the disease. Based on the stage, doctors can also decide how to treat bone cancer.
The staging system of bone cancer goes from 1 to 4 (I to IV). A higher stage means that cancer is more advanced. So, stage I means that cancer is only found in the bone, and stage IV means that it has spread to other tissues.
Staging can be determined by a standardized system known as TNM, which stands for Tumor, Nodes, and Metastasis.
- T measures the tumor and how large it is. Doctors will try to find out if there is only one tumor or several spots.
- N measures the lymph nodes and if they are taken. This is the first stage of cancer spread, but it is not the same as metastasis.
- M measures metastasis to distant organs. When other organs are already taken by cancer, the disease is very serious regardless of how large the tumor is and how many lymph nodes are taken.
After a biopsy is taken, we can also determine the grade of cancer by looking at the cells and evaluating how different they look from healthy cells. Bone cancer can be graded from 1 to 3. So, we have low-grade cancer (G1) when it is very similar to healthy cells, middle-grade cancer (G2) when it is starting to look very different, and high-grade cancer (G3) when the tissue has lost every major characteristic. The more differentiated it is, the more aggressive it will be.