A Survival Prediction Model For Patients With Locally Advanced Gastric Cancer Treated With Neoadjuvant Chemotherapy Combined With Radical Surgical Resection Based On Inflammatory Marker

ObjectiveGastric cancer is the fifth most common neoplastic disease and has the fourth highest mortality rate in the world.Most patients in China have already reached advanced stages when diagnosed,with high rates of distant metastases and poor prognosis.Neoadjuvant chemotherapy(NACT)combined with radical surgical resection has become a standard treatment pattern for patients with locally advanced gastric cancer.Most clinical studies depend on pathological or hematological markers to evaluate the prognosis of patients,but single markers have limitations in assessing the prognosis of patients.Therefore,in this study,we analyzed the hematological markers,inflammatory markers,nutritional markers and the change values of each marker at Pre-NACT and Post-NACT of patients with locally advanced gastric cancer,explored the relationship between the above-mentioned markers and prognosis,and established a survival prediction model,aiming to provide a theoretical reference basis for clinical decision-making and patient prognosis.MethodsClinicopathological data,hematological markers of Pre-NACT and Post-NACT were collected from January 1,2017 to December 31,2019 from gastric cancer patients who were attended the First Hospital of Lanzhou University for combined radical surgical resection with NACT,the overall survival(OS)of patients was obtained by follow-up.Paired-samples t-test or non-parametric test was used to compare the differences of hematological indicators between Pre-NACT and Post-NACT in gastric cancer patients;Cox single-factor and multi-factor analysis was used to screen independent risk factors affecting patients’ OS;Kaplan-Meier method was used to analyze the survival differences of gastric cancer patients in different independent risk factor groups;Cox regression analysis was used to calculate the coefficients of each The coefficients of the independent risk factors were calculated by Cox regression analysis,and the Cox proportional risk regression models predicting patients at 1,3 and 5 years were constructed using R software and presented in the form of a nomogram,and the models were evaluated using the index of concordance(C-index),calibration curve and receiver operating characteristic curve(ROC)to assess the calibration and discrimination of the model.In addition,the best cut-off value was calculated by calculating the risk score(Risk score)of the patients,using the ROC curve,and dividing them into high and low risk groups to analyze the survival differences of patients with different risk levels.Results1.129 patients with gastric cancer were included in this study.Among them,103 were male and 26 were female;72(55.8%)were aged <60 years and 57(44.2%)were aged ≥60 years;53(41.1%)were N0 stage and 76(58.9%)were N1-N3 stage in yp N stage;89(69%)were TRG grade 0-2 and 40(31%)were grade 3.The follow-up period was 1-71 months,and a total of 66 cases(51.2%)died and 63 cases(48.8%)survived as of the follow-up date.2.RBC,HGB,PLT,UA,NLR,PLR,SII,d NLR,WLR,ALB and PNI decreased significantly post-NACT compared to pre-NACT(P<0.05),while RDW,MLR,CEA,AFP and D-D increased significantly post-NACT(P <0.05).The PT,PTA,APTT and BMI did not change significantly.3.The results of Cox univariate and multifactor analysis suggested that age,yp N stage,TRG and Pre-NACT NLR were independent risk factors affecting patients’ prognosis;survival analysis at different risk factor levels showed that the older the age(P=0.02),the later the yp N stage(P=0.002),the worse the TRG(P<0.001),the worse the Pre-NACT NLR The higher the value(P < 0.001),the worse the prognosis of the patients;further,the survival prediction model for gastric cancer patients at 1,3 and 5years was established,and the ROC analysis yielded an area under the curve of 0.893,0.824 and 0.689 for 1,3 and 5 years,respectively,with a C-index of 0.742,and the calibration curve showed a good fit of the model,indicating that the model has good discrimination and calibration.In addition,the prognosis of patients in the High Risk group was worse compared to the Low Risk group(P < 0.001).Conclusions1.Age,yp N staging,TRG grading,and Pre-NACT NLR as independent risk factors affecting the prognosis of patients with locally progressive gastric cancer treated with neoadjuvant chemotherapy combined with radical surgical resection;2.The survival prediction model established in this study has good discrimination and calibration and can provide a theoretical reference basis for clinical decision making and prognosis of patients’ providers.