TNM Staging Group T / M Sub classification N0 N1 N2 N3 T1 T1a T1b IA IIA IIIA IIIB IA IIA IIIA IIIB T2 T2a T2b IB IIA IIIA IIIB IIA IIB IIIA IIIB T3 T3 IIB IIIA IIIA IIIB T4 T4 IIIA IIIA IIIB IIIB M M1a M1b IV IV IV IV IV IV IV IV

Table 2: The 7th edition of TNM staging system for lung cancer [22].