Simultaneous integrated boost intensity-modulated radiotherapy for locally advanced non-small cell lung cancer in Chinese population: A retrospective study

// Yujin Xu 1, 2 , Xiao Zheng 1, 2 , Xue Bai 3 , Pu Li 3 , Honglian Ma 1, 2 , Jin Wang 1, 2 , Xiao Hu 1, 2 and Ming Chen 1, 2 1 Department of Radiation Oncology, Zhejiang Cancer Hospital, Hangzhou, 310022, China 2 Zhejiang Provincial Key Laboratory of Radiation Oncology, Hangzhou, 310022, China 3 Department of Radiation Physics, Zhejiang Cancer Hospital, Hangzhou, 310022, China Correspondence to: Ming Chen, email: chenming@zjcc.org.cn Keywords: non-small cell lung cancer, integrated boost intensity-modulated radiotherapy, local control, overall survival Received: March 03, 2017 Accepted: March 31, 2017 Published: April 13, 2017 ABSTRACT Objectives: To evaluate the clinical efficacy and toxicity of simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) for patients with locally advanced non-small cell lung cancer (NSCLC). Results: All patients completed definitive radiotherapy and 74 (85.1%) patients administrated platinum-based chemotherapy. The median radiation dose was 50.4Gy to PTV and 64.4 Gy simultaneously to the PGTV. The overall response rate (ORR) was 57.5% (50/87). The median duration of follow up was 24.6 months. The 1, 2, 3-year local control rate was 79.0%, 66.1%, and 60.5%, respectively. The 1, 2, 3-year overall survival (OS) rate was 89.7%, 56.7%, and 30.6%, respectively. Subgroup analysis showed that the median OS in concurrent chemoradiation (CCRT) was much better than non-CCRT (35.7 vs. 26.4 months) (HR: 0.52, 95% CI: 0.32–0.95, P = 0.033). Twenty-two (25.3%) patients experienced acute grade 3 esophagitis and 10 (11.5%) experienced acute grade ≥ 3 radiation pneumonitis. There were 2 (2.6%) late grade 3 pulmonary toxicity and no late grade ≥ 3 esophageal toxicity was observed. Materials and Methods: A total of 87 patients with locally advanced NSCLC who received SIB-IMRT from Jan. 2009 to Dec. 2012 in our hospital were retrospectively analyzed. Male accounted for 88.5%, with a median age of 61 years old. The SIB-IMRT plans were designed to deliver 50.4–64.0 Gy in 28–33 fractions (1.8–2.1 Gy/fraction) to PTV while simultaneously delivering 60.0–74.3 Gy in 28–33 fractions (2.0–2.5 Gy/fraction) to PGTV. Conclusions: SIB-IMRT, especially with concurrent chemotherapy, appears to be an effective and safe option to treat patients with locally advanced NSCLC. More prospective clinical studies should be warranted.