The impact of tumor size on survival in T3 non-small cell lung-cancer with direct extension.

Abstract

e20033 Background: Tumor size is an important prognostic variable that affects clinical decision-making in NSCLC including the use of adjuvant therapy. However, the association between tumor size and survival in a subset of patients who have T3 NSCLC with direct extension into nearby structures (T3dx) has not been explicitly characterized. We hypothesize that tumor size impacts survival and prognosis within this cohort. Methods: Patients with T3dxin 2006-2013 who underwent lobectomy or pneumonectomy were identified in the National Cancer Database. Patients who received neoadjuvant therapy or had positive margins were excluded. Tumor size was categorized based on cutoffs used by current staging guidelines and patients were stratified by pathologic N stage (see table). Cox proportional hazard models were used to measure the independent impact of tumor size on survival. Results: Overall, 0.1-3cm tumors exhibit superior 5-year survival compared to 3.1-5cm and >5cm tumors. Tumor size is significantly associated with survival in N0 patients but not in N1 and N2 patients. Use of adjuvant chemotherapy is associated with improved survival in the overall cohort and all subgroups; however, use of adjuvant chemoradiation may be associated with inferior survival in the overall cohort. Conclusions: Larger tumor size is associated with inferior survival in T3dx in the absence of nodal disease. T3dx requires a more tailored approach to adjuvant therapy than other T3 subgroups. Adjuvant chemotherapy appears to benefit all patients with T3dx; however, the role of adjuvant chemoradiation is less clear. [Table: see text]