Clinical Efficacy Analysis Of Hypofractionated Radiotherapy For Patients With Locally Advanced Non-small Cell Lung Cancer

Objective: The aim of this study was to compare the efficacy and toxic side effects of hypofractionated radiotherapy and conventional fractionated radiotherapy for locally advanced non-small cell lung cancer(LA-NSCLC),to evaluate the efficacy and safety of fractionated radiotherapy for LA-NSCLC,and to analyze the factors affecting the survival and prognosis of LA-NSCLC,so as to provide a valid reference for clinical treatment and prognosis assessment.Methods: 82 patients with LA-NSCLC radiotherapy treated with radiotherapy admitted to the Department of Oncology of Wuhan Fifth Hospital between January2012 and December 2019 were collected and divided into hypofractionated radiotherapy(HFRT)group and conventional fractionated radiotherapy(CFRT)group according to the radiotherapy pattern.The recent efficacy,progression-free survival(PFS)and overall survival(OS)of the patients were calculated.The Kaplan-Meier method was used to calculate the 1-,2-,and 3-year PFS rates and1-,2-,and 3-year OS rates,and the survival curves were plotted;the patients were further divided into radiotherapy-only subgroup,radiotherapy with sequential chemotherapy subgroup,and radiotherapy with concurrent chemotherapy subgroup,to compare the efficacy of different treatment regimens under the two radiotherapy modalities.The univariate analysis was carried out by Log-Rank test with gender,age,ECOG PS(Eastern Cooperative Oncology Group performance status),pathological type,maximum tumor diameter,clinical stage,treatment regimen,bioequivalent dose(BED),duration of radiotherapy,radiotherapy technique,and recent efficacy,etc.Further,the multivariate analysis of P<0.05 factors in univariate analysis was carried out by Cox model.The acute and late radiation toxicities were graded with reference to the diagnostic grading criteria of radiation damage established by the Radiation Therapy Oncology Group(RTOG),and the incidence of toxicities between the two groups was compared.All data were statistically analyzed by SPSS 28.0.Results: All the patients received complete radiotherapy.The recent efficacy: 14 cases had complete remission(CR),20 had partial remission(PR),7 had stable disease(SD),and 1 had disease progression(PD)in the HFRT group,wiht an overall response rate(ORR)of 80.95% and a disease control rate(DCR)of 96.3%. In the CRFT group,6 cases had CR,18 had PR,14 had SD,2 had PD,and the ORR was 60.00%,the DCR was 95.00%.The ORR in HFRT group was significantly higher than that in CFRT group(P=0.037),but there was no significant difference in DCR between the two groups(P>0.05).Long-term survival: The median follow-up time was 16 months(2 to 72 months)until December 31,2022,with no lost cases.In the HFRT group,the median PFS was13 months(2～72 months),with 1-year,2-year and 3-year PFS rates of 50.8%,5.1%and 4.8%,respectively,while the median PFS of CFRT group was 9 months(2～50 months),with 1-year,2-year and 3-year PFS rates of 30.2%,3.0% and 2.5%.The median PFS and PFS rates in HFRT group were better than that in CFRT group(P=0.041).The median OS of HFRT group was 19 months(2～72 months),with 1-year,2-year and 3-year OS rates of 73.1%,33.9% and 23.5%,respectively;while the median OS of CFRT group was 13 months(3～66 months),with the 1-year,2-year and 3-year OS rates of 52.5%,15.0% and 10.0%.The median OS and OS rates in HFRT group were better than that in CFRT group(P=0.037).In subgroup analysis by treatment regimen,OS rates in the HFRT group were not statistically significant among different treatment subgroups(P=0.054).And the survival benefit in CFRT group: radiotherapy with concurrent chemotherapy subgroup > radiotherapy with sequential chemotherapy subgroup > radiotherapy-only subgroup(P=0.026).The results of univariate analysis showed that survival time was longer for ECOG score of 0 to 1,maximum tumor diameter ≤ 5 cm,radiotherapy course ≤6 weeks,use of IMRT technique,BED ≥74.4Gy,and recent efficacy of CR and PR(P<0.05),where radiotherapy technique,radiotherapy time,BED,and recent efficacy were independent prognostic factors(P<0.05).There was no significant difference in the incidence of radiation side effects between the two groups(P<0.05).Conclusion:1.Compared with conventional fractionated radiotherapy,hypofractionated radiotherapy has advantages in recent efficacy and long-term survival.It can shorten the course of radiotherapy and improve BED without significantly increasing side effects,making it a new option for inoperable LA-NSCLC patients.2.There was no significant difference in OS rate among different treatment schemes in HFRT group,but the long-term effect of CFRT group was as follows: radiotherapy with concurrent chemotherapy subgroup > radiotherapy with sequential chemotherapy subgroup > radiotherapy-only subgroup.3.Radiotherapy technique,radiotherapy time,BED and short-term effect were independent factors affecting the prognosis of patients with LA-NSCLC.