Once all of the necessary diagnostic tests have been completed, doctors will use this information to "stage" the tumor, a process that designates how aggressive the tumor is and how far it has spread. This information will then be used to design the appropriate treatment strategy. The standard staging protocol for sarcomas is the American Joint Committee on Cancer's TNM system:
- "T" represents the tumor's size
- "N" represents the spread of sarcoma cells to lymph nodes
- "M" represents the spread, or metastasis, to other parts of the body
An additional factor known as histologic grade, involving the microscopic examination of the sarcoma cells, is used to stage soft tissue sarcomas.
Once staged, the sarcoma will receive a grading using Roman numerals I to IV (I for a small tumor that has not spread to lymph nodes or other organs and IV for the most aggressive tumor that has spread). These numbers get combined with letters A and B, denoting the diameter of the tumor. (A for tumors with a diameter of less than 5 cm; B for tumors with a diameter greater than 5 cm.)
