Analysis Of Risk Factors Related To Lung Adenocarcinoma With Bone Metastasis And Establishment Of Risk Prediction Model

ObjectiveTo analyze the clinical characteristics and screen out independent risk factors of lung adenocarcinoma with bone metastasis and to assess the clinical value of these ones in predicting bone metastasis so as to provide reference for early clinical diagnosis of bone metastasis in lung adenocarcinoma.MethodsBased on the inclusion and exclusion criteria,we retrospectively selected patients who were diagnosed with lung adenocarcinoma for the first time as the study subjects in the Department of respiratory medicine of the First Affiliated Hospital of Zhengzhou University from January 2016 to January 2020,and finally 210 cases were selected.All patients were confirmed to be primary lung adenocarcinoma by pathological examination.We divided them into bone metastasis group(n=94)and non-bone metastasis group(n=116).The gender,age,occupation,family history of lung cancer and smoking status were recorded.The symptom,location and maximum diameter of primary tumor,bone metastasis,EGFR gene mutation,tumor marker levels and alkaline phosphatase levels were collected.Statistical software SPSS21.0 was used to analyze the data and summarize the clinical characteristics of them.Multivariate logistic regression was used to explore the risk factors of bone metastasis with lung adenocarcinoma and establish a risk prediction model.Finally,receiver operator characteristic curve was used to test the predictive value of the risk prediction model.Results1.The clinical characteristics of lung adenocarcinoma patients with and without bone metastasis:The common symptoms were cough,expectoration,chest tightness,shortness of breath,chest pain and blood in sputum,and there was no significant difference between the two groups(P>0.05).There was no significant difference between the two groups(P>0.05).The most common sites of bone metastasis were vertebrae,ribs and hip,followed by scapula,femur,sternum and skull,and the least were humerus,fibula and clavicle.2.Univariate analysis:There were no significant differences in gender,age,smoking,family history of lung cancer and occupation between the two groups(P>0.05).The number of patients with clinical symptoms in bone metastasis group was more than that in non bone metastasis group,and the number of patients with primary lung adenocarcinoma diameter>3cm was more than that in non bone metastasis group,and the differences were statistically significant(P<0.05).There were significant differences in EGFR gene mutation positive rate,CEA level,CYFRA 21-1 levels and ALP levels between the two groups(P<0.05).3.Multivariate logistic regression analysis:EGFR gene mutation(OR=15.389,95%CI:6.208-38.148,P<0.001),CEA>5 ng/ml(OR=15.146,95%CI:6.515-35.211,P<0.001)and primary lung adenocarcinoma diameter>3cm(OR=3.099,95%CI:1.401-6.853,P=0.005)were the independent risk factors.4.Construction and validation of risk prediction model:The risk model for bone metastasis of lung adenocarcinoma was constructed as follows:In[P/(1-P)]=4.013+(2.734×EGFR gene mutation)+(2.718×CEA level)+(1.131×primary lung adeno-carcinoma diameter).P is the probability of bone metastasis of lung adenocarcinoma.Variable assignment:"EGFR gene mutation positive"=1,"CEA>5ng/ml"=1,"diameter of primary lung adenocarcinoma>3cm"=1,other assignments are 0.The ROC curve was used to verify the predictive value of the risk prediction model.The AUC of the area under the curve was 0.907,95%CI(0.863～0.951),P<0.001.ConclusionBone metastasis is common in the spine and ribs.EGFR gene mutation is an independent risk factor for bone metastasis in patients with lung adenocarcinoma.Combined with the diameter of primary lung adenocarcinoma and CEA level can effectively predict the risk of bone metastasis in lung adenocarcinoma.