Differential analysis of local and regional failure in locally advanced non-small cell lung cancer patients treated with concurrent chemoradiotherapy

Abstract Background and purpose Concurrent chemoradiotherapy (CCRT) is the standard treatment in locally advanced non-small cell lung cancer (NSCLC) patients. In clinical practice, the primary tumor (PT) and involved lymph nodes (LNs) receive the same radiotherapy dose. This study investigates differences between local failure (LF) and regional failure (RF). Material and methods Patients were irradiated with 66Gy in 24 fractions (using IMRT) combined with daily low dose cisplatin. The PT and LNs were contoured on the planning CT-scan registered with a 18 FDG-PET-scan. Log 10 (Volume) and SUVmax of PT and LNs, location (LNs versus PT), performance status, age and gender were tested as prognostic factors for lesion failure using cox regression analysis. Results In total, 226 patients were analyzed. LF or RF as first event was seen in 37 PT (16%) and 14 LNs (6%). Log 10 (Volume), location and SUVmax were significantly associated with failure in univariate analysis. In multivariate analysis, only log 10 (Volume) remained as a significant factor. Conclusions A LF and RF as first event of respectively 16% and 6% were observed in locally advanced NSCLC patients treated with CCRT. This difference was primarily associated with the difference in log 10 (Volume) of the primary tumor and lymph nodes.