Analysis Of Prognostic Factors Of Radiotherapy In Patients With Locally Advanced Non-Small Cell Lung Cancer

AimsTo investigated the prognostic factors in patients with locally advanced non-small cell lung cancer(LA-NSCLC)underwent radiotherapy,and provide references and more clinical basis for clinical and prognosis assessment of LA-NSCLC.Materials and Methods177 patients suffered from LA-NSCLC and admitted to our institution to receive radiotherapy-based treatment from January 1st,2012 to June 30 th,2016 were initially enrolled.81 cases of them underwent concurrent chemoradiotherapy,and the rest,among whom 91 cases underwent sequential or alternate chemotherapy and 5 cases chose no chemotherapy,refused the concurrent chemoradiotherapy.BED(Biological effective dose)is defined as the total dose required to compare the specific biological effects of an organization under different sub-dose treatment conditions and BED= n×d×(1+d/?/?).In the formula above,n is the number of times,d is a sub-dose,n×d actually is the total dose(D),and ?/? of different tissues can be searched on the table.The best tangent value of the total BED of radiotherapy received by LANSCLC patients was found by the cutoff Finder application software.The survival rate was estimated by Kaplan-Meier method.And the single factor survival analysis was carried out by Log-rank method.Subgroup analysis was carried out on patients with lymph node metastasis staging as N3 in LA-NSCLC.The multi-factor analysis of P<0.1 factors in single factor analysis adopts Cox stepwise regression model.ResultsThe median follow-up time of patients was 23 months(3-70 months).The survival rates of 1,2 and 3 years were 81.7%,47.6% and 34.5%,respectively.Using the cutoff Finder application,the best tangent value for the total BED of radiotherapy received by LA-NSCLC patients was 78.98Gy(P=0.022),with a sensitivity of 92.6%(96%-86.5%)and a specificity of 19.6%(31.8%-11.3%).There was no significant statistical difference between the survival period of concurrent chemoradiotherapy group and the non-concurrent chemoradiotherapy group(P=0.493).Subgroup analysis found that when the prognosis of LA-NSCLC lymph node metastasis was diagnosed as N3,the patients with lateral mediastinal lymph node metastasis had the best prognosis,while the prognosis was the worst when the patients had bilateral supraclavicular lymph node metastasis.The results were statistically significant(P=0.006).Single factor analysis suggested that the number of chemotherapy cycles ?4 weeks(P=0.004),BED > 78.98gy(P=0.028),combined superior vena cava syndrome(P=0.033),combined COPD(chronic obstructive pulmonary disease(COPD)(P=0.001)were associated with the prognosis(all P<0.05).Multivariate analysis was performed for factors with P < 0.1 in the single factor analysis and the following conclusion was found:the number of chemotherapy cycles ?4(P=0.007),the radiotherapy delay time > 1 weeks(P=0.044),and whether or not to combine COPD(P=0.002)were independent factors affecting the prognosis of LA-NSCLC patients(all P<0.05).ConclusionsThe number of chemotherapy cycles is greater than 4 cycles,the delay time of radiotherapy > 1 weeks,and the patients had COPD before treatment are all independent influencing factors of LA-NSCLC patients.