Correlation Between The Expression Status Of PD-L1 And Clinicopathological Characteristics And The Efficacy Of Immunotherapy In Non-small Cell Lung Cancer

Purpose:To explore the correlation between the expression status of PD-L1 and clinicopathological characteristics and the efficacy of immunotherapy in non-small cell lung cancer.Materials and Methods:Inclusion criteria:86 patients with non-small cell lung cancer diagnosed by pathology from May 2018 to December 2019 in Shaanxi Province Tumor Hospital were collected and the expression of PD-L1 was detected.The expression of PD-L1(SP263)was detected by the in vitro diagnostic on the Ventana benchmark platform,the level of PD-L1 was expressed in the form of tumor proportion score(TPS).The expression level of PD-L1<1%is negative,>1%is positive,1%-49%is low expression,?50%is high expression.The expression status and clinicopathological characteristics of PD-L1 in 86 patients with non-small cell lung cancer were observed(including gender,age,smoking index,ECOG score,TNM stage,lymph node metastasis,pathological type,histological grading,Ki67index,and driver gene status).The correlation between the expression of PD-L1 and the clinicopathological characteristics was analyzed by?~2 test or Fisher,s exact probability method to analyze the relationship between PD-L1 expression status and clinicopathological characteristics.The response rate(ORR)of Pembrolizumab immunotherapy for 4 cycles was observed.Result:1.In 86 NSCLC patients,the positive expression(>1%)of PD-L1 was 86.0%(74/86),low expression(1%-49%)accounted for 48.8%(42/86),high expression(?50%)accounted for 37.2%(32/86);negative expression(<1%)14.0%(12/86).2.The level of PD-L1 high expression(?50%)is 8.1%(3/37)and 59.2%(29/49)in TNM stage?-?and?stage respectively,which in TNM stage?stage(?50%)was significantly higher than stage?-?,the difference was statistically significant(P<0.001);the level of high expression of PD-L1(?50%)was 55.6%(30/54)with lymph node metastasis and no lymph node metastasis was 6.2%(2/32),which in the lymph node metastasis was significantly higher than that in the lymph node non-metastasis,the difference was statistically significant(P<0.001);There was no statistically significant difference in PD-L1 expression status with gender,age,smoking index,and ECOG score(P>0.05).3.The level of PD-L1 high expression(?50%)is 0%(0/6)and 5.6%and 68.1%(30/44)in histological grade?(high differentiation),grade?(medium differentiation),grade?(low differentiation),which in histological grade III(low differentiation)was significantly higher than grade?(high differentiation),grade?(medium differentiation),the difference was statistically significant(P<0.001);The level of PD-L1 high expression(?50%)were 40.0%(2/5),9.0%(1/11),22.5%(7/31),56.4%(22/39)in Ki67 index negative,1+,2+,3+,which in Ki67 index 3+was significantly higher than that of Ki67index negative,1+,2+,the difference was statistically significant(P<0.001);There was no significant difference between pd-l1 expression state and pathological type(P>0.05).4.Genetic testing was performed in 56 of the 86 NSCLC patients,EGFR sensitive mutants accounted for 23%(13/56,among which 7 cases were 19Del;4 cases of L858R;2cases of residual mutation type),and about 9%of KRAS mutations(5/56),about 16%(9/56)of ALK fusion and other mutation types,about 52%(29/56)of driver gene negative.Statistical analysis showed that there was no statistically significant difference between PD-L1 expression status and driver gene status(P>0.05).5.Among the 14 patients treated with Pembrolizumab,7 patients received Pembrolizumab monotherapy and 7 patients received Pembrolizumab combined with chemotherapy,the ORRs of 4 cycles were 57.1%(4/7),and the efficacy evaluations were all PR and no CR;Among the 14 patients,9 patients had low level of PD-L1 expression(1%-49%),5 patients had PD-L1 high level of PD-L1 expression(?50%),and the ORR of patients with low expression was 44.5%(4/9)for 4 cycles of immunotherapy,and the efficacy evaluation was PR without CR;the ORR of 4 cycles of immunotherapy in patients with high expression is 80.0%(4/5),and the efficacy evaluation is PR,without CR.It indicates that ORR receiving Pembrolizumab immunotherapy has a certain correlation with PD-L1 expression(1%-49%vs?50%).Conclusion:1.The expression state of PD-L1 was significantly correlated with lymph node metastasis,TNM stage IV,histological grade III and Ki67 index 3+,suggesting that PD-L1 is highly expressed in NSCLC patients with adverse prognostic factors.2.There is no correlation between PD-L1 expression status and gender,age,smoking index,ECOG score,pathological type and driver gene status of NSCLC patients.3.The expression state of PD-L1(1%-49%vs?50%)has a certain correlation with the therapeutic effect of Pembrolizumab.PD-L1 as a predictor of the therapeutic effect of Pembrolizumab needs further clinical research.