Cancer staging is based on the size of the primary lesion, its extend of spread to regional lymph nodes, and the presence or absence of metastases. The international TNM system ( T, primary tumor, N, regional lymph node involvement, M, metastasis ) is currently used cancer staging. In the TNM system, T1, T2, T3 and T4 describe the increasing size of tumor. NO, N1, N2 and N3 indicate progressively advancing lymph node involvement, and MO and M1 reflects the absence or presence of distinct metastases. It is worth notice that mist statistical data related to cancer survival are based on the stage rather than the grade of the tumor.
Stages of cancerStage 0: Carcinoma in site- Early form
Stage 1: Localized
Stage 2: Early locally advanced
Stage 3: Late locally advanced
Stage 4: Metastasized – cancer has spread other organs