The Predictive Value Of Peripheral Blood Inflammatory Indexes On The Short Term Effect Of Radiotherapy In Limited Stage Small Cell Lung Cancer

Small cell lung cancer(SCLC)as a type of neuroendocrine cancer,accounts for about 13%-17% of the incidence of lung cancer.It has the characteristics of rapid proliferation,high invasiveness,avoidance of apoptosis and immune escape.Limited stage small cell lung cancer(LS-SCLC)accounts for about one third of all SCLC cases.Currently,the combination of chemotherapy and radiotherapy is the standard treatment for LS-SCLC,which has greatly improved the prognosis of LS-SCLC patients.Radiotherapy is particularly important in the treatment of LS-SCLC patients.The efficacy of radiotherapy is affected by many factors.At present,there are few clinical indicators that can be used to predict the efficacy of radiotherapy.The relationship between inflammation and tumors is a hot topic in the field of tumor therapy,and tumor-related inflammation has been considered as one of the signs of malignant tumors.Peripheral blood cells such as lymphocytes,platelets,neutrophils and monocytes can control and shape the tumor microenvironment(TME)in the form of autocrine or paracrine,and it’s important for tumor immune response.Neutrophil to lymphocyte ratio(NLR),platelet to lymphocyte ratio(PLR)and lymphocyte to monocyte ratio(LMR)are several emerging inflammatory markers,which can directly reflect the inflammatory state of the body.Peripheral blood inflammatory indicators have been confirmed to be related to the survival and prognosis of tumors,but there are few indexes on peripheral blood inflammatory indicators and the efficacy of radiotherapy.This study intends to explore the value of peripheral blood inflammatory indexes in predicting the short-term effect of radiotherapy in patients with LS-SCLC.Objective:By analyzing the peripheral blood indexes of LS-SCLC patients before and after radiotherapy,including neutrophil count(NEUT#)and its change value ΔNEUT,lymphocyte count(LYM#)and its change value ΔLYM,monocyte count(MONO#)and its change value ΔMONO,platelet count(PLT)and its change value ΔPLT,neutrophil to lymphocyte ratio(NLR)、platelet to lymphocyte ratio(PLR)、 lymphocyte to monocyte ratio(LMR),and the lymphocyte nadir during radiotherapy with short-term radiotherapy efficacy in LS-SCLC patients.To explore the clinical predictive value of peripheral blood indexes for the short-term radiotherapy efficacy of LS-SCLC patients.Methods:From January 2016 to June 2020,Forty-eight patients with LS-SCLC lung cancer who received radiotherapy in Baoding First Central Hospital were retrospectively analyzed.The clinical data of patients’ age,smoking history,gender,ECOG score,tumor location were collected.Blood routine within 3days before radiotherapy,blood routine within 3 days after radiotherapy,and the lymphocyte nadir during radiotherapy were collected.Chest CT scans were collected 1 week before and 4-6 weeks after radiotherapy.According to RECIST1.1,the short-term radiotherapy efficacy was divided into radiotherapy sensitive group(CR+PR)and radiotherapy insensitive group(SD+PD).Compare the difference of the clinical data and blood routine indexes between the two groups before and after radiotherapy.Compare the difference of the lymphocyte nadir between the two groups.By drawing the receiver working characteristic curve(ROC curve)of meaningful peripheral blood indexes and radiotherapy effect.To determine the cut-off value of peripheral blood indexes to predict radiotherapy curative effect,and to divide peripheral blood indexes into high value group and low value group with this value,respectively to compare if there was a significant difference in the efficacy of recent radiotherapy.The test standard P<0.05 was considered statistically significant.Results:1.Relationship between clinical parameters and the efficacy of recent radiotherapy.A total of 48 cases were enrolled from January 2016 to June 2020,including 2 cases of CR,34 cases of PR,12 cases of SD and 0 cases of PD.There was no significant difference in clinicopathological data(gender,age,smoking or not,tumor location)between radiotherapy sensitive group and nonradiotherapy sensitive group(P>0.05).2.Relationship between peripheral blood indexes and recent radiotherapy efficacy(1)There were statistically significant differences in PLR between the two groups before and after radiotherapy(P<0.05).There was statistically significant differences in the lymphocyte nadir during radiotherapy between the two groups(P<0.05).There was no significant differences in peripheral blood NEUT#,LYM#,MONO#,PLT,NLR,LMR between the two groups before and after radiotherapy(P>0.05).There was no significant difference in ΔNEUT,ΔLYM,ΔMONO,ΔPLT between the two groups(P>0.05).(2)The ROC curve is drawn based on the PLR before radiotherapy as the data variable,the maximum Youden index was 0.367,the cut-off value was128.31,the area under the curve(AUC)was 0.675(P<0.05).The objective response rate(ORR)of the low PLR group was 86.7%,the objective response rate(ORR)of the high PLR group was 55.6%,and the difference between the two groups was significant(P<0.05).According to the ROC curve of PLR as the data variable after radiotherapy,the maximum value of Youden index was0.345,the cut-off value was 280.44,AUC was 0.642(P>0.05).(3)The ROC curve was drawn based on the lymphocyte nadir in radiotherapy as a data variable.Youden maximum index was 0.583,the cut-off value was 0.33,AUC was 0.795(P<0.05).Taking the optimal cut-off value as the cut-off point,the ORR of the low value group was 40.0%,and the ORR of the high value group was 90.90%.There was significant difference between the two groups(P<0.05).Conclusion:1.There was a significant difference in PLR before and after radiotherapy between the radiotherapy sensitive group and the nonsensitive group.2.The PLR value before radiotherapy can be used as a predictor of the short-term radiotherapy efficacy of LS-SCLC patients.Patients in the low PLR group(PLR<128.31)have better short-term radiotherapy efficacy.The PLR value after radiotherapy has no predictive value for the short-term radiotherapy effect.3.The lymphocyte nadir during radiotherapy can be used as a predictor of the efficacy of radiotherapy of LS-SCLC patients.Patients in the high lymphocyte count group(lymphocyte count≥0.33)have better short-term radiotherapy efficacy.