ABSTRACT
Objective To externally validate the accuracy of combined use of neutrophil-lymphocyte ratio (NLR),V20,and Dmean in predicting the incidence of grade Ⅲ or higher radiation-induced lung injury (RILI) in lung cancer patients.Methods A total of 166 lung cancer patients,who participated in the model establishment were selected into the internal validation group,and 85 lung cancer patients who received intensity-modulated radiotherapy in our department between June 2016 and June 2018 were assigned into the external validation group.The incidence rate of grade 3 or higher RILI was statistically compared between the internal and external validation groups.Multivariate logistic analysis was performed for NLR,V20 and Dmean The discrimination degree of the predictive model was evaluated by using ROC curve in combination with NLR,V20 and Dmean The calibration degree of the predictive model was assessed by Hosmer-Lemeshow test.Results The incidence rate of grade 3 or higher RILI in the internal and external validation groups was 23.8％ and 22.9％.Multivariate logistic analysis demonstrated that NLR,V20 and Dmean significantly differed in the internal validation group (P=0.032,0.006 and 0.005).However,only V20 significantly differed in the external validation group (P=0.038).The discrimination and calibration degree of RILI was almost consistent between the internal and external validation groups (both P＞0.05).The area under the curve (AUC) predicted by NLR,V20,Dmean and the combination of three indexes were 0.611,0.646,0.682 and 0.775 in the internal validation group,and 0.544,0.702,0.658 and 0.754 in the external validation group,respectively.The calibration degree in the internal validation group was P=2.797and 0.834,P=2.452 and 0.653 in the external validation group.Conclusion Combined application of NLR,V20 and Dmean can accurately predict the incidence of grade Ⅲ or higher RILI in lung can cancer patients,which has been validated by external dataset.
ABSTRACT
Objective To observe the objective response rate, survival and safety of radiotherapy combined with Iressa for patients with locally advanced non-small cell lung cancer ( NSCLC) unsuitable for surgery or concurrent chemoradiotherapy. Methods The patients with locally advanced NSCLC unsuitable for surgery or concurrent chemoradiotherapy were recruited and received thoracic intensity-modulated radiotherapy ( IMRT) combined with Iressa 250 mg daily. Results A total of 30 patients were enrolled between July 2014 and March 2017. Twenty-nine patients were analyzed. At 1 month after radiotherapy,the complete response (CR) was 0,partial response (PR) was 21(72％),stable disease (SD) was 6(21％), progressive disease (PD) was 2(7％),the disease control rate (CR+PR+SD) was 93％,and the objective response rate was 72％. The median follow-up time was 25 months. Fourteen ( 48％) patients died,and 15 (52％) survived. Twenty-three (79％) patients obtained PD including local progression in 18(62％) and distant metastasis in 14(48％). The median survival time (MST) was 26 months and the median PFS was 11 months. The 1-year OS and PFS were 79％ and 44％,and the 2-year OS and PFS were 55％ and 18％. Univariate analysis demonstrated that smoking history and disease stage were influencing factors for OS ( P=0. 035,0. 031) . Moreover, disease stage, the primary tumor diameter, the volume of GTV and PTV were influencing factors for PFS (P=0. 000,0. 016,0. 039,0. 030). Multivariable analysis revealed that disease stage and the volume of PTV were independent prognostic factors for PFS (P=0. 000,0. 012).Two patients ( 7％) developed grade 3 acute adverse events and 7 ( 24％) experienced grade 2 acute irradiation pneumonitis. Conclusions For patients with locally advanced NSCLC unsuitable for surgery or concurrent chemoradiotherapy,IMRT combined with Iressa yields high objective response rate and well tolerance. The long-term clinical efficacy remains to be validated.
ABSTRACT
Objective To study the dosimetry and safety of the non-coplanar IMRT plan for advanced lung cancer.Methods The two groups IMRT plans were designed with coplanar (5,7F) and non-coplanar field (5,7F-n) for patients.To compare the dosimetry of two groups and perform 4 patients F7-n IMRT plan.Results With the increase of the fields in each group PTV's CI were improved (all P =0.000),especially the 7F-n plan PTV's Dmean,Dmax,V95％ and HI also were improved (P=0.001,0.001,0.009,0.000) ; in the coplanar group each lung' s V5 increased (P =0.000,0.002,0.000) and whole lung's Dmean increased (P =0.000),but non-coplanar group whole lung's and contralateral lung's V5 reduce (P =0.001,0.005).Between the groups,7F-n plan PTV's indicators were all improved to compared with 5F plan (all P =0.000),and each lung's V20 reduced (all P =0.000),and whole lung's Dmean,V30,contralateral lung' s V5 reduced (P =0.000,0.001,0.000),and spinal cord' s Dmax also reduced (P =0.033),but ipsilateral lung's V5 and heart's Dmean increased (P =0.000,0.003);with compared to 7F plan,the 7F-n's ipsilateral lung's V5 and heart's Dmean also increased (P =0.000,0.048),but whole lung' s and contralateral lung's V5 decreased (all P =0.000).Four patients were performed successfully non-coplanar IMRT treatment,no collision occurred.Conclusions 7 fields non-coplanar IMRT plan not only improve the dose distribution of PTV,but also effectively control the volume of low dose lung increase,lung V20 and Dmean reduce too.Thus recommended to use this design in patients with advanced lung cancer for radiotherapy