Prognostic impact based on tumor diameter of pathological N1 lymph node metastases for non-small cell lung cancer

The N parameter in the tumor-node-metastasis (TNM) classification of lung cancer is categorized according to the location of nodal metastasis, while that for some other cancers are classified according to the size and number of metastatic foci. In lung cancer, the impact of size of nodal metastasis on prognosis is unclear. This analysis aims to examine whether it is possible to subdivide the pathological N (pN) factor based on the tumor diameter of lymph node metastases.