ABSTRACT
Objective:Simultaneous integrated boost radiation technique in limited-stage small cell lung cancer is lack of evidence. This prospective study aims to evaluate whether the simultaneous integrated boost is as efficacious and safe as conventional fractionated radiotherapy.Methods:Patients diagnosed with treatment-naive and confirmed limited-stage SCLC were eligible. Participants were randomly assigned (1: 1) to receive simultaneous integrated boost radiotherapy (PGTV 60.2 Gy/2.15 Gy/28F, PTV 50.4 Gy/1.8 Gy/28F) or conventional fractionated radiotherapy (PTV 60 Gy/2 Gy/30F). The primary endpoint was 2-year progression-free survival, and the secondary endpoints were 2-year overall survival, 2-year local-regional recurrence-free survival and toxicity.Results:Between February 2017 and July 2019, 231 patients were enrolled. We analyzed 216 patients whose follow-up time was more than 2 years or who had died, among whom 106 patients in the conventional fractionated radiotherapy group and 110 patients in the simultaneous integrated boost radiotherapy group. The median follow-up time was 37 months (95% CI: 35.2-38.7). The 2-year progression-free survival rates were 45.2% vs. 38.2%( HR=1.22, 95% CI: 0.87-1.72, P=0.2). The 2-year overall survival rates were 73.5% vs. 60.9%( HR=1.35, 95% CI: 0.90-2.04, P=0.14). The 2-year local-regional recurrence-free survival rates were 68.7% vs. 69.9%( HR=0.98, 95% CI: 0.62-1.56, P=1.0). Multivariate analysis showed that early radiotherapy yielded better 2-year progression-free survival, overall survival and local-regional recurrence-free survival than delayed radiotherapy in two groups ( HR=1.69, 95% CI: 1.18-2.41, P=0.003; HR=1.72, 95% CI: 1.09-2.70, P=0.018; HR=1.66, 95% CI: 1.01-2.73, P=0.046). Tumor staging was an influencing factor of overall survival (stage Ⅲ vs. stage Ⅰ-Ⅱ, HR=3.64, 95% CI: 1.15-11.57, P=0.028). The most common grade 3-4 adverse events were myelosuppression (21.7% vs. 15.4%, P=0.83), radiation pneumonitis (4.7% vs. 2.7%, P=0.44) and radiation esophagitis (3.8% vs. 1.8%, P=0.51). Conclusions:Simultaneous integrated boost radiotherapy yields equivalent efficacy and toxicities to conventional fractionated radiotherapy for limited-stage small cell lung cancer. Early radiotherapy can enhance clinical prognosis.
ABSTRACT
Objective@#To evaluate the efficacy, toxicity and cosmetic outcomes of hypofractionated simultaneous integrated boost intensity-modulated radiotherapy (IMRT-SIB) after breast conservative surgery (BCS) for early breast cancer patients.@*Methods@#A total of 76 patients with stage TisT1-2N0M0 breast cancer treated with BCS were enrolled in the analysis. The patients who underwent breast radiotherapy without regional lymph node irridiation and hypo fractionated IMRT/VMAT were used. All patients received whole breast IMRT/VMAT with tumor bed SIB. The doses delivered to the whole breast was 42.4 Gy in 16 fractions, and the dose delivered to tumor bed for SIB was 49.6 Gy in 16 fractions. Cosmetic evaluation was based on the Harvard system. Acute and late toxicities were scored according to CACAT version 3.0. Survival and recurrence rates were calculated by Kaplan-Meier method. The univariate and multivariate analysis were conducted with logistic regression.@*Results@#The median follow-up was 29 months (range 16-40 months). The follow-up rate was 100%. The 1-, 2-and 3-year overall survival rates were 100%. No recurrence or metastasis was observed in this study. The incidence of grade 1 acute skin toxicity was 68.4%, grade 2 was 7.9%. The late skin toxicity of grade 1 was 13.1%, grade 2 was 2.6%.In all, 82.4% of patients had excellent and good cosmetic outcome. The Mean dose of the tumor bed was predictive factor for grade 2 dermatitis.@*Conclusion@#The efficacy, cosmetic effect, the acute and late treatment-related toxicity of hypofractionated IMRT/VMAT-SIB in patients with early breast cancer following BCS might be acceptable. A longer follow-up is needed to define the efficacy on outcomes.@*Trial registration@#Chinese clinical trial registry, ChiCTR1800016287