Single T factors predict survival of patients with resected stage-IIB non-small-cell lung cancers

In the seventh edition of TNM Classification of Malignant Tumours (TNM) staging, the stage-IIB category for lung cancer is comprised of four factors: lymph-node metastasis, chest-wall invasion, large tumor size (> 7 cm), and same-lobe nodules. Tumors are further classified into eight sub-categories based on each TN factor or factor combinations. This study evaluated the prognostic value of each TN factor or combinations for resected stage-IIB non-small-cell lung cancer (NSCLC).

We retrospectively studied 186 consecutive patients who had resections for NSCLC at Chiba University Hospital and were diagnosed as stage IIB according to the seventh edition of TNM staging.

Five-year survivals for each stage IIB were: T2bN1M0 = 47 ± 12% (± standard error); T3 (chest-wall invasion; N0M0) = 59 ± 7%; T3 (large tumor> 7 cm)=72 ± 11%; T3 (same-lobe nodules) = 78 ± 5%; T3 (invasion + > 7 cm)=44 ± 16%; T3 (invasion+same-lobe nodules) = 25 ± 22%; T3 (>7cm+same-lobe nodules) = 0%; and T3 (invasion + > 7 cm +same-lobe nodules)=0%. Among the four single factors, same-lobe nodules had the best prognoses, whereas T2bN1M0 had the worst prognoses. Comparing cases with single factors and multiple factors that decided stage IIB, cases with multiple factors had poorer prognoses (P=0.02).

The stage-IIB category is comprised of eight sub-categories, with either single factors or factor combinations; these sub-categories have different prognoses. The worst survivals were for cases with T2bN1M0 as a single factor or for cases with multiple factors, although these represented a small proportion of resected stage-IIB NSCLC cases.