ASO Author Reflections: Proposed Nodal Categories for Future Editions of the TNM Classification of Non-small Cell Lung Cancer

Excerpt

Nodal staging is one of the most reliable indicators of prognoses for patients with non-small cell lung cancer (NSCLC) and thus is indispensable in determining the optimal treatment. In the eighth edition of the TNM Classification of Malignant Tumors, the four N categories (N0, N1, N2, and N3) remained the same as before. However, he International Association for the Study of Lung Cancer (IASLC) proposed further subdivisions of pN1 and pN2 patient groups who had a heterogeneous prognosis. As proposed, N1 would be further subdivided into N1a (single) and N1b (multiple), and N2 would be divided into N2a1 (single station without N1), N2a2 (single station with N1), and N2b (multiple stations). This classification required additional evaluation before being considered for future revisions of the TNM staging system.1 …