Analysis Of Risk Factors For Recurrence Of Locally Advanced Cervical Cancer After Radiotherapy And Chemotherapy And Preliminary Construction Of Nomogram Prediction Model

Objective: Analyze the risk factors of local advanced cervical cancer recurrence after radiotherapy and chemotherapy.Based on the risk factors,a risk line chart model for predicting LACC recurrence after radiotherapy and chemotherapy is constructed.At the same time,internal verification and external verification are carried out to provide tools and more accurate clinical early warning for predicting LACC recurrence after radiotherapy and chemotherapy.Assist clinical medical staff to identify patients with LACC recurrence after radiotherapy and chemotherapy effectively and personally,adjust diagnosis and treatment plans in time,and reduce the risk of LACC recurrence after radiotherapy and chemotherapy.Methods: By means of retrospective case-control study,459 patients with LACC were randomly divided into training set(320 cases)and validation set(139 cases)from May2016 to December 2019 in the Department of Tumor Radiotherapy,First Affiliated Hospital of Anhui Medical University.The training set is used for the construction,evaluation and internal validation of the line chart,and the validation set is used to verify the repeatability validation outside the model.All patients are required to complete a 2-year follow-up and follow up through the clinic once every 6 months to detect tumor recurrence.with recurrence after radiotherapy and chemotherapy as the follow-up outcome event,and the last follow-up time is August 2022.It is divided into recurrent group and non-recurrent group according to whether LACC recurs after radiotherapy and chemotherapy.Clinical data of selected LACC patients were analysed,including age,body mass index(BMI),family history of cervical cancer,diabetes,hypertension,cardiovascular disease(CHD,MI,angina pectoris,heart failure,transient ischemic patients,etc.),histological type,TNM stage,degree of differentiation,tumor diameter,pelvic lymph node metastasis,depth of invasion,tumor interstitial invasion,surgery,time of radiation,course of chemotherapy.dose of radiation,squamous cell carcinoma antigen(SCC-Ag),D-dimer,hemoglobin,platelet and leukocyte levels,etc.The data were analyzed with SPSS24.0 software,single factor analysis with β 2 test,multiple factor analysis with binary COX regression analysis to screen out the independent risk factors for recurrence of LACC patients after radiotherapy and chemotherapy.A line chart was constructed with R software to predict the recurrence probability of LACC patients after radiotherapy and chemotherapy.Bootstrap self-sampling method was used to validate the model of recurrence line chart of patients with LACC after radiotherapy and chemotherapy(sampling times were set to 1000 times);rms program package was used to calculate the differentiation degree of consistency index(C-CP)value test line chart,and calibration curve and subject work characteristic(ROC)curve were drawn to evaluate the prediction efficiency of the model of recurrence line chart of patients with LACC after radiotherapy and chemotherapy.Graphic calibration method and Hosmer-Lemes fitting excellence test were used to evaluate the calibration degree of the model of recurrence line chart;P < 0.05 was taken as the difference with statistical significance.Results: The positive rate of recurrence after radiotherapy and chemotherapy was 20%(64/320)in LACC model training group.Compared with the clinical data of the training set,there were statistical differences in TNM stage,differentiation degree,tumor diameter,pelvic lymph node metastasis,invasion depth,SCC-Ag level,D-dimer and other data(P< 0.05);COX regression analysis showed that the middle and low differentiation(OR= 2.170,95%CI:1.177 ～ 4.001,P= 0.013),tumor diameter > 4 cm(OR= 2.061,95%CI:1.117 ～ 3.803,P= 0.021),pelvic lymph node metastasis(OR=2.370,95%CI:1.289 ～ 4.355,P= 0.005),infiltration depth ≥ 1/2(OR=2.505,95%CI:1.360 ～ 4.614,P= 0.The independent risk factors were listed separately and quantified in the form of a score,and then the cumulative scores of all the independent risk factors were matched to the outcome scale to generate a line chart that predicts the probability of recurrence after radiotherapy and chemotherapy in LACC patients.Column diagram showed that the middle and low differentiation score was 83,tumor diameter > 4 cm was 79,pelvic lymph node metastasis score was 93,depth of invasion ≥ 1/2 was 99,SCC-Ag> 1.5 cm was 81,D-dimer > 0.5 mg/L was 100,the C index of the column diagram model was 0.824,the H-L fitting excellence test was ≥2=13.528,P= 0.078,the calibration curve approached the ideal curve,the area under the internal validation ROC curve was 0.804,and the external validation ROC curve AUC value of the column diagram was 0.792.Conclusion: The independent risk factors of recurrence after radiotherapy and chemotherapy in LACC patients were middle and low differentiation,tumor diameter >4 cm,pelvic lymph node metastasis,invasion depth ≥ 1/2,SCC-Ag> 1.5 μg/L,D-dimer > 0.5 mg/L.The line-chart model constructed in this paper has high prediction accuracy,and can reliably evaluate the risk of recurrence after radiotherapy and chemotherapy in LACC patients,showing good practical value.