Matched-pair comparison of outcome of patients with clinical stage I non-small cell lung cancer treated with resection or stereotactic radiosurgery.

Abstract

7040 Background: Stereotactic body radiotherapy (SBRT) is an alternative to surgery alone for certain patients with clinical stage I non-small cell lung cancer (NSCLC), but comparing their effectiveness is difficult because of differences in patient selection and staging. Methods: Two databases were combined which contained 132 patients treated by lobectomy (LR) and 48 by sublobar resection (SLR) and 137 patients managed with SBRT after negative staging between 1999-2009. We compared rates of overall survival (OS), disease-free survival (DFS), and locoregional control (LRC) between patients treated with surgery and SBRT to each other and in relation to possible prognostic factors. We then performed a matched-pair analysis comparing surgery and SBRT results. Median follow-up for the entire study population was 25.8 months. Results: On univariate analysis, OS was significantly correlated with histology, the Charlson Comorbidity Index, tumor size, aspirin use, and use of SBRT; DFS was correlated only with histology; and no variable was significantly correlated with LRC. Multivariate analysis found improved OS in patients with adenocarcinoma and those undergoing surgical resection. The NSCLC “not otherwise specified” histology was associated with poorer DFS. Overall survival was significantly poorer for SBRT patients in the matched-pair analysis than for patients treated with surgery, but DFS and LRC were not significantly different between these groups. Conclusions: Our retrospective study has demonstrated similar LRC and DFS in patients treated with SBRT or surgery, but worse OS in the former group, when patients were matched for prognostic factors. Our investigation suggests that randomized trials are needed to eliminate selection bias in treatment assignment in order to accurately compare outcomes between these approaches.

Definition of stereotactic body radiotherapy

“…Two Japanese and Dutch studies described excellent OS rates of 70 % after 5 years [ 34 ] and 85 % at 3 years [ 35 ], respectively. Two recent matched-pair analyses reported equivalent OS [ 36 ] and equivalent disease-free survival rates [ 37 ] after SBRT and lobectomy. Consequently, SBRT is a viable treatment option in the situation of surgical treatment being refused by the patient.…”