The Impact of Does Reduction Elective Nodal Irradiation in Limited-Stage Small Cell Lung Cancer

Abstract

Purpose/Objective(s)To evaluate the clinical outcomes of simultaneous dose reduction to elective nodal area with intensity-modulated radiation therapy (SIR-IMRT) vs conventional intensity-modulated radiation therapy(C-IMRT) in patients with limited-stage small-cell lung cancer (LS-SCLC).Materials/MethodsPatients with LS-SCLC who received definitive SIR-IMRT or C-IMRT from Jan.2010 to December.2013 in our hospital were retrospectively analyzed. In SIR-IMRT group, the planning gross target volume (GTVP) was generated with GTV plus a 0.5cm margin. The prescribed dose was 60Gy in 30 fractions to the GTVP, and 54Gy in 30 fractions to the planning target volume (PTV). In the C-IMRT group, the prescribed dose was 60Gy in 30 fractions to the whole PTV. Radiation-related toxicities were estimated according to Common Terminology Criteria for Adverse Events (version 3.0). The primary end point was loco-regional recurrence-free survival (LRFS), and the secondary end points include Overall survival (OS) and toxicity. Loco-regional recurrence was classified as local relapse and regional relapse. LRFS and OS were estimated with Kaplan-Meier method.ResultsA total of 137 patients were included, 72 patients in SIR-IMRT and 65patients in C-IMRT, respectively. After propensity score matching, only 84 patients were included in this study, with 42 patients in each group. Fifty-three patients experienced treatment failure, 24 patients with locoregional recurrence and 40 patients with distant metastasis, 11 patients experienced both locoregional and distant failure. Locoregional recurrence was developed in 10 patients (7 cases in the GTV, 3 cases in the regional field) in SIR-IMRT group and in 14 patients (11 cases in the GTV, 3cases in the regional field) in C-IMRT group. Grade 3 and above radiation-induced lung toxicity developed in 2 patients in SIR-IMRT group and 5 patients in C-IMRT group, respectively. Grade 3 and above radiation-related esophagitis was observed in 3 patients and 5 patients, respectively. 1- and 3-year OS were 90.5% and 51.0% in the SIR-IMRT group, vs. 83.3% and 45.0% in the C-IMRT group (P=0.066).ConclusionReducing the irradiation dose to the elective nodal region may reduce radiation-induced toxicities without compromising local-regional control and overall survival. Purpose/Objective(s)To evaluate the clinical outcomes of simultaneous dose reduction to elective nodal area with intensity-modulated radiation therapy (SIR-IMRT) vs conventional intensity-modulated radiation therapy(C-IMRT) in patients with limited-stage small-cell lung cancer (LS-SCLC). To evaluate the clinical outcomes of simultaneous dose reduction to elective nodal area with intensity-modulated radiation therapy (SIR-IMRT) vs conventional intensity-modulated radiation therapy(C-IMRT) in patients with limited-stage small-cell lung cancer (LS-SCLC). Materials/MethodsPatients with LS-SCLC who received definitive SIR-IMRT or C-IMRT from Jan.2010 to December.2013 in our hospital were retrospectively analyzed. In SIR-IMRT group, the planning gross target volume (GTVP) was generated with GTV plus a 0.5cm margin. The prescribed dose was 60Gy in 30 fractions to the GTVP, and 54Gy in 30 fractions to the planning target volume (PTV). In the C-IMRT group, the prescribed dose was 60Gy in 30 fractions to the whole PTV. Radiation-related toxicities were estimated according to Common Terminology Criteria for Adverse Events (version 3.0). The primary end point was loco-regional recurrence-free survival (LRFS), and the secondary end points include Overall survival (OS) and toxicity. Loco-regional recurrence was classified as local relapse and regional relapse. LRFS and OS were estimated with Kaplan-Meier method. Patients with LS-SCLC who received definitive SIR-IMRT or C-IMRT from Jan.2010 to December.2013 in our hospital were retrospectively analyzed. In SIR-IMRT group, the planning gross target volume (GTVP) was generated with GTV plus a 0.5cm margin. The prescribed dose was 60Gy in 30 fractions to the GTVP, and 54Gy in 30 fractions to the planning target volume (PTV). In the C-IMRT group, the prescribed dose was 60Gy in 30 fractions to the whole PTV. Radiation-related toxicities were estimated according to Common Terminology Criteria for Adverse Events (version 3.0). The primary end point was loco-regional recurrence-free survival (LRFS), and the secondary end points include Overall survival (OS) and toxicity. Loco-regional recurrence was classified as local relapse and regional relapse. LRFS and OS were estimated with Kaplan-Meier method. ResultsA total of 137 patients were included, 72 patients in SIR-IMRT and 65patients in C-IMRT, respectively. After propensity score matching, only 84 patients were included in this study, with 42 patients in each group. Fifty-three patients experienced treatment failure, 24 patients with locoregional recurrence and 40 patients with distant metastasis, 11 patients experienced both locoregional and distant failure. Locoregional recurrence was developed in 10 patients (7 cases in the GTV, 3 cases in the regional field) in SIR-IMRT group and in 14 patients (11 cases in the GTV, 3cases in the regional field) in C-IMRT group. Grade 3 and above radiation-induced lung toxicity developed in 2 patients in SIR-IMRT group and 5 patients in C-IMRT group, respectively. Grade 3 and above radiation-related esophagitis was observed in 3 patients and 5 patients, respectively. 1- and 3-year OS were 90.5% and 51.0% in the SIR-IMRT group, vs. 83.3% and 45.0% in the C-IMRT group (P=0.066). A total of 137 patients were included, 72 patients in SIR-IMRT and 65patients in C-IMRT, respectively. After propensity score matching, only 84 patients were included in this study, with 42 patients in each group. Fifty-three patients experienced treatment failure, 24 patients with locoregional recurrence and 40 patients with distant metastasis, 11 patients experienced both locoregional and distant failure. Locoregional recurrence was developed in 10 patients (7 cases in the GTV, 3 cases in the regional field) in SIR-IMRT group and in 14 patients (11 cases in the GTV, 3cases in the regional field) in C-IMRT group. Grade 3 and above radiation-induced lung toxicity developed in 2 patients in SIR-IMRT group and 5 patients in C-IMRT group, respectively. Grade 3 and above radiation-related esophagitis was observed in 3 patients and 5 patients, respectively. 1- and 3-year OS were 90.5% and 51.0% in the SIR-IMRT group, vs. 83.3% and 45.0% in the C-IMRT group (P=0.066). ConclusionReducing the irradiation dose to the elective nodal region may reduce radiation-induced toxicities without compromising local-regional control and overall survival. Reducing the irradiation dose to the elective nodal region may reduce radiation-induced toxicities without compromising local-regional control and overall survival.