Patterns and correlates of treatment failure in relation to isodose distribution in non-small cell lung cancer: An analysis of 1522 patients in the modern era. Issue 2 (November 2017)

• Record Type: Journal Article
• Authors: Pezzi, Todd A.; Tang, Chad; Swanick, Cameron W.; Fang, Penny; Hess, Kenneth; Xu, Ting; Hahn, Stephen M.; Chang, Joe Y.; Liao, Zhongxing; Gomez, Daniel
• Is Part Of: Radiotherapy and oncology. Volume 125:Issue 2(2017:Nov.)
• Page Start: 325
• Page End: 330
• Publication Date: 2017-11
• Subjects: NSCLC -- Dose–response -- BED -- Radiation therapy; Oncology -- Periodicals; Radiotherapy -- Periodicals; Tumors -- Periodicals; Medical Oncology -- Periodicals; Neoplasms -- radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiothérapie -- Périodiques; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Electronic journals; 616.9940642
• DOI: 10.1016/j.radonc.2017.09.018
• Languages: English
• ISSNs: 0167-8140

Abstract

Abstract: Background and purpose: To examine the relationship between radiation dose and tumor control in limited stage non-small cell lung cancer (NSCLC). Materials and methods: We searched a database of 1552 patients who received radiation therapy for non-metastatic NSCLC between 2000 and 2016. The primary endpoint was freedom from in-field failure. Results: Increasing BED correlated with decreasing estimated gross tumor volume–planning target volume expansion, and on multivariable analysis increasing BED was associated with an increased chance of field-edge failures (hazard ratio [HR] 1.032, 95% confidence interval [CI] 1.004–1.062, P = 0.027). Increasing BED also correlated with improved freedom from in-field failure on multivariable analysis (HR 0.978, 95% CI 0.964–0.993, P = 0.003), with the dose–response curve showing a sigmoidal relationship between increasing BED and freedom from in-field failure. Conclusion: In this large study of patients treated in the modern era with varying dose fractionation regimens, higher BED was associated with improved freedom from in-field failure, and that this relationship appeared to be consistent with the classically described sigmoid shape. We also found that increased BED was associated with higher field-edge failures, implying that margin size may need to be further studied in patients receiving ablative regimens of radiation.