To determine how far the cancer has spread, your cancer care team uses a process of analysis known as staging. The stage of your cancer impacts your treatment and the prognosis for recovery.
A number of different staging systems can be used to classify tumors. The TNM staging system assesses tumors in three ways:
size of the primary tumor (T)
whether it has spread to lymph nodes (N)
whether it has spread (metastasized) to other organs (M).
Once the T, N, and M are determined, a number of I, II, III, or IV is assigned, with stage I being early stage and IV being advanced. In general, the lower the number, the less the cancer has spread. A higher number, such as stage IV, denotes a more serious case. Your doctor will review your test results and tell you the stage of your cancer.