Establishing a TNM-like risk classification for metachronous second pulmonary adenocarcinoma in patients with previously resected pulmonary adenocarcinoma

Shen-Shen Fu, Yu-Zhen Zheng, Xian-Yu Qin, Xing-Ping Yang, Piao Shen, Wei-Jie Cai, Xiao-Qiang Li, Hong-Ying Liao