Postoperative radiotherapy for stage II or III non–small cell lung from 1988 to 2014.

Abstract

e20013 Background: In 2006 ASCO, Brian E. Lally et al. reported the association between survival and postoperative radiotherapy (PORT) in patients with resected non–small-cell lung cancer (NSCLC). We now undertook a update analysis using the latest data. Methods: Updated data were obtained by the Surveillance, Epidemiology and End Results database. We analyzed stage II or III NSCLC patients diagnosed between 1988 and 2014. Results: A total of 20645 patients were selected, with a median follow-up time of 3.3 years. Predictors for the use of PORT included age less than 50 years, higher AJCC stage, T3-4 tumor stage, larger tumor size, advanced node stage, greater number of lymph nodes involved, and a higher ratio of lymph nodes involved to lymph nodes sampled. On multivariate analysis, male sex, older age, T3-4 tumor stage, N2 node stage, fewer sampled lymph nodes, higher positive lymph nodes and higher ratio of lymph nodes involved to lymph nodes sampled had a negative impact on survival. PORT had a significant adverse effect on survival, regardless of all patients (P < 0.001), or N0 subgroup ( P< 0.001) or N1 subgroup (P< 0.001). For N2 subgroup, PORT did not have a significant effect of on survival (P < 0.117). This is different from the result Brian E. Lally et al. reported in ASCO 2006. Conclusions: Postoperative radiotherapy is detrimental to resected N0 or N1 NSCLC patients and should not be used routinely for such patients. The role of postoperative radiotherapy in the treatment of N2 tumours is not clear and may warrant further research.