The IASLC Lung Cancer Staging Project: proposals for the revision of the TNM stage groupings in the forthcoming (seventh) edition of the TNM Classification of malignant tumours.
The T3 category of the 7th Edition of the TNM classification of non-small cell lung cancer (NSCLC) has added two factors that do not appear in the 6th Edition, large tumor size (>7 cm) and pulmonary metastasis of the same lobe. These factors are considered to have different biological and clinical features. In the present study we assessed the outcome of surgical resection as a first line therapy for T3 NSCLC. A total of 145 patients who were diagnosed according to the TNM 7th Edition with pathologic T3 NSCLC received surgical resection in our institution as a first line treatment. The outcomes of their treatment were analyzed. The 5-year survival rate was 46.9 %. On the basis of the 6th TNM Edition, the 5-year survival rate was 63.1 % for patients diagnosed with T2 disease (large tumor size), 44.3 % for patients diagnosed with T3 disease, and 33.1 % for patients diagnosed with T4 disease (pulmonary metastasis of the same lobe). There were no significant correlations between these categories and overall survival (OS). Nevertheless, 6th Edition T factors were found to be significantly correlated with lymph node status (p < 0.01). The univariate analyses showed that age, lymph node metastasis, and curative resection had significant effects on OS. In addition, the multivariate analysis identified age and N factor as independent prognostic factors in this cohort. Indications for surgical resection as a first line therapy in T3 NSCLC should be based on N factors and patient age. Lymph node metastasis, especially N2 disease, was increasingly frequent in patients with 6th Edition T classifications.