Clinical Characteristics And Influencing Factors Of Benign And Malignant Solitary Pulmonary Nodules

Objectives To identify the main influencing factors for malignant solitary pulmonary nodules(SPN)and to establish a mathematical prediction model for benign and malignant SPN by analyzing the clinical,imaging and laboratory factors of the SPN with clear pathological characteristics;meanwhile,to observe the changes of nodules in patients with undefined nodules by follow-up.Methods 1 Research subjects:Patients who received radiological examination of the lungs and whose relevant examination results were consistent with the diagnosis of SPN were selected in the Affiliated Hospital of North China University of Science and Technology from September 2015 to September 2017.2 Research methods:Patients diagnosed with SPN were selected as research subjects.For patients with clear pathological characteristics through surgery,they were divided into the benign group and the malignant group according to the pathological results.However,patients with unclear pathological characteristics were included in the follow-up group to observe the changes of nodules.Single factor analysis was performed for patients with clear pathological characteristics on the following factors:gender,age,family history of malignancy,smoking history,first clinical symptoms,tumor markers,nodule position,maximum diameter of the nodule,density of the nodule,lobulation,spiculation,vacuole,cavitation,pleural indentation,vascular convergence sign,bronchial truncation and satellite focal factors.The t test was used for measurement data,and the chi-square test was performed for categorical data.Multivariate logistic regression analysis was used to screen for independent influencing factors of malignant SPNs.The independent influencing factors selected were used to construct a benign and malignant prediction model,and appropriate intercept points were selected to calculate sensitivity and specificity.SPSS17.0 Software was used for all statistical analysis.P<0.05 was considered statistically significant.For the follow-up group with an unclear pathological characteristic through surgery and other invasive examinations,the changes of the nodules were followed up.Results 1 Totally 104 patients were diagnosed with SPN.94 of them obtained histopathological results to confirm the pathological nature,including 68 malignant and26 benign nodules.The other 10 patients were followed up to observe the change of nodules,of which 4 were excluded due to poor follow-up compliance.There were no significant changes in 4 patients during follow-up,however,the diameter of nodules in 2patients was increased during follow-up.Surgical resection was performed for the above2 patients,and post-operative pathology revealed that 1 patient was small cell lung cancer and 1 patient was squamous cell lung cancer.2 Single factor analysis indicated that statistically significant differences were found in age(t=1.355,P<0.05),smoking history(χ~2=10.241,P<0.05),tumor markers(χ~2=15.039,P<0.05),spiculation(χ~2=15.103,P<0.05),pleural indentation(χ~2=18.053,P<0.05)and vascular convergence sign(X~2=5.970,P<0.05)between malignant and benign nodules.However,there were no statistically significant differences in gender(χ~2=0.147,P>0.05),family history of malignancy(χ~2=0.751,P>0.05),first clinical symptoms(χ~2=1.396,P>0.05),nodule position(χ~2=0.695,P>0.05),maximum diameter of the nodule(t=1.378,P>0.05),density of the nodule(χ~2=3.494,P>0.05),lobulation(χ~2=0.147,P>0.05),vacuole(χ~2=0.320,P>0.05),cavitation(χ~2=0.628,P>0.05),bronchial truncation(χ~2=0.000,P>0.05)and satellite focal(χ~2=2.357,P>0.05)between malignant and benign nodules.3 Multifactor logistic regression analysis showed that age(OR=1.079,P=0.045),tumor markers(OR=6.075,P=0.026),pleural indentation(OR=10.424,P=0.045)and vascular convergence sign(OR=14.157,P=0.028)were independent prognostic factors for benign and malignant SPN.4 Based on the independent factors for SPN by logistic regression analysis,the mathematical prediction model for the malignant possibility of pulmonary nodules was constructed as follows:P=e~x/(1+e~x)(x=-13.656+(0.076×age)+(1.804×tumor marker)+(2.344×pleural indentation)+(2.650×vascular convergence sign);e=natural logarithm;age unit=year;tumor marker:1 meant higher than normal,0 meant normal;pleural indentation and vascular convergence sign:1 meant yes,0 meant no).5The ROC curve analysis of the mathematical prediction model demonstrated that the model had a statistical significance in the differential diagnosis of SPN(P<0.05),and the area under the ROC curve was 0.914(>0.9).Therefore,the accuracy of the prediction model was relatively high.Conclusions 1 Age,smoking history,tumor markers,spiculation,pleural indentation and vascular convergence sign were associated with benign and malignant SPN.Meanwhile,age,tumor markers,pleural indentation and vascular convergence sign were independent prognostic factors for benign and malignant SPN.2 The mathematical prediction model has statistical significance and high diagnostic accuracy in the differential diagnosis of benign and malignant solitary pulmonary nodules.3 Follow-up strategies to observe nodular changes in patients,the follow-up process may appear to increase the number of nodules and possible malignant transformation.