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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.
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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
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PURPOSE : To investigate the feasibility of intensity modulated radiotherapy (IMRT) as a method of boost radiotherapy following the initial irradiation by the conventional anterior / posterior opposed beams for centrally located non-small-cell lung cancer through the evaluation of dose distributions according to the various boost methods. MATERIALS AND METHODS : Seven patients with T3 or T4 lung cancer and mediastinal node enlargement who previously received radiotherapy were studied. All patients underwent virtual simulation retrospectively with the previous treatment planning CTs. Initial radiotherapy plans were designed to deliver 40 Gy to the primary tumor and involved nodal regions with the conventional anterior / posterior opposed beams. Two radiation dose levels, 24 and 30 Gy, were used for the boost radiotherapy plans, and 4 different boost methods (a three dimensional conformal radiotherapy (3DCRT), 5, 7, and 9-beams IMRT) were applied to each dose level. The goals of the boost plans were to deliver the prescribed radiation dose to 95% of the planning target volume (PTV) and minimize the volumes of the normal lungs and spinal cord irradiated above their tolerance doses. Dose distributions in the PTVs and lungs, according to the four types of boost plans, were compared in the boost and sum plans, respectively. RESULTS : The percentage of lung volumes irradiated >20 Gy (V20) were reduced significantly in the IMRT boost plans compared with the 3DCRT boost plans at the 24 and 30 Gy dose levels (p=0.007 and 0.031 respectively). Mean lung doses according to the boost methods were not different in the 24 and 30 Gy boost plans. The conformity indexes (CI) of the IMRT boost plans were lower than those of the 3DCRT plans in the 24 and 30 Gy plans (p=0.001 in both). For the sum plans, there was no difference of the dose distributions in the PTVs and lungs according to the boost methods. CONCLUSION : In the boost plans the V20s and CIs were reduced significantly by the IMRT plans, but in the sum plans the effects of IMRT to the dose distributions in the tumor and lungs, like CI and V20, were offset. Therefore, in order to keep the beneficial effect of IMRT in radiotherapy for lung cancer, it would be better to use IMRT as a whole treatment plan rather than as a boost treatment
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Humans , Lung Neoplasms , Lung , Radiotherapy , Radiotherapy, Conformal , Retrospective Studies , Spinal CordABSTRACT
PURPOSE: This study was undertaken to evaluate the treatment outcome and side effects of accelerated radiotherapy (RT) using concomitant boost for stage III non-small cell lung cancer (NSCLC). METHODS: Between April 1991 and December 1994, 102 patients with stage III NSCLC who had the favorable prognostic factors by CALGB criteria, were treated with concomitant boost radiotherapy. Patients were treated with standard large fields to 54 Gy in 6 weeks. The boost treatment was administered concomitantly during the last 2 weeks with a dose of 13 Gy in 10 fractions. The interfraction interval was at least 6 hours. The total tumor dose was 66-70 Gy, given over 6 weeks. RESULTS: With 30 months median follow-up period for survivors, median survival was 15 months with 2 and 3-year overall survival rates of 34% and 19%, respectively. Thirty patients (29%) who had achieved complete remission after RT showed significantly better 2-year survival rates than those without complete remission (58% vs 22%, p 0.001). Local failure and distant metastases as the first or only failure occurred in 40 (44%) and 13 (14%), respectively, and ultimate local and distant failure rates were 45% and 29%, respectively. Although Grade IV esophageal complication of T-E fistula was observed in one patient, most patients with pulmonary complication showed mild, transient radiation pneumonitis. CONCLUSION: This result suggests that the treatrnent of stage III NSCLC with concomitant boost RT may improve survival rates without enhanced radiation induced toxicity compared with conventional RT. Further investigation of dose escalation by conformal radiotherapy of combining chemotherapy and accelerated RT is warranted.