The Prediction Model Of Refractory Small Cell Lung Cancer

Objective:To establish a prediction model of refractory SCLC by analyzing the relationship of clinical factors with refractory SCLC.Methods:1. Factors study: A retrospective study of 329 small cell lung cancer（SCLC） patients was preformed form April 2008 to September 2014 at the Department of Cancer Center at the First Hospital of Jilin University.According to the time from first-line chemotherapy to relapse or progress,patients was divided into sensitive group and refractory group, 329 patients with SCLC were enrolled in the study with 239 patients in sensitive group and 90 patients in refractory group.In this study, the following clinical factors were in enrolled, including age,gender,smoking index, clincal stages, superior vena cava syndrome（SVCS）,chemotherapy redimens, chemotherapeutic cycles, chemotherapy effect of two cycles ect.2. Establish prediction model: By applying univariate and multivaraiate logistic regression analysis to identify independent risk factors that affected refractory SCLC. At the result of multivaraiate logistic regression, a new combined prediction variable produce, the PRE₁, and established the regression equation of the PRE₁. Using the receiver-operating characteristic curve（ROC） valued the new prediction variable,got the area under the curve, and found out the best diagnosis according to Youden index（sensitivity + specificity- 1）. The statistical significance was defined by P value< 0.05.Results:1. Logistic univariate regression analysis was mainly to determine the correlation of various factors with the refractory SCLC.There were statistically significant factors mainly including gender, smoking index, SVCS, clinical stage,chemotherapy regimens and thoracic radiotherapy. Futher we found that smoking index>400, with SVCS, extensive disease, compared with EP regimen selected EC regimen and thoracic radiotherapy were the poor prognosis factors of refractory SCLC.2. The area under ROC curve of prediction model was 0.721（95%CI:0.657-0.784）. According to Youden index,the best diagnosis point（0.306） wasfound out,which sensitivity and specificity was 61.1% and 79.9%, respectively.Conclusions:1. smoking index>400, with SVCS, extensive disease,compared with EP regimen selected EC regimen and thoracic radiotherapy were the poor prognosis factors of refractory SCLC.2. The prediction model with high sensitivity and specificity was established by the independent risk factors, which can assist clinicians to distinguish refractory patients from the initial SCLC.