The Value Of ¹⁸F-FDG PET/CT In The Differential Diagnosis Of Benign And Malignant Solitary Pulmonary Nodule

BackgrouedWith the wide application of computed tomography（CT）in clinical practice,whether low-dose CT physical examination screening or high-resolution spiral CT（HRCT）tumor diagnosis,staging,follow-up and efficacy evaluation,the economic value and social benefits brought by CT are increasingly recognized by clinical practice.Especially the clinical application of low-dose spiral CT（LDCT）and tumor patients in clinical staging and the postoperative follow-up process,more and more significance is not clear or it is difficult to qualitative isolation of pulmonary nodules（SPN）was found,it can be a benign lesions（in lymph nodes and lungs inflammation or fibrosis）,precancerous lesions（atypical adenomatous hyperplasia）,Congenital or malignant lesions（e.g.lung adenocarcinoma）.Although many imaging methods,such as high-resolution computered tomography（HRCT）and CT enhancement,can help doctors distinguish between benign and malignant pulmonary nodules,their imaging findings are overlapping,and lung puncture biopsy or bronchoscopy are invasive.In addition,there are certain false negatives and high economic costs,so qualitative diagnosis is still difficult.Therefore,the purpose of this study was to study the value of ¹⁸F-FDG PET/CT imaging SUVmax in the diagnosis of benign and malignant solitary pulmonary nodules（SPN）.ObjectiveTo explore the value of ¹⁸F-FDG PET/CT imaging standardized maximum exposure（SUVmax）in the differential diagnosis of benign and malignant solitary pulmonary nodules.MethodsThe ¹⁸F-FDG PET/CT data of ninty-three patients with isolated pulmonary nodules examined in our department from January two thousand and nineteen to October two thousand and twenty were retrospectively analyzed,SUVmax of the lesion was measured,the pathological results were taken as the gold standard,to analyze the value of SUVmax in the differential diagnosis of benign and malignant solitary pulmonary nodules,the rank sum test and receiver operating characteristic curve（ROC curve）were used to analyze the optimal threshold of SUVmax and the diagnostic efficiency of benign and malignant nodules,the isolated subsolid pulmonary nodules were scanned by the same machine VHRCT,and their CT signs were analyzed to compare the sensitivity,specificity and accuracy of VHRCT,PET/CT and their combination in the diagnosis of benign and malignant SPN.ResultsAmong the ninty-three patients,there were seventy-three malignant nodules and twenty benign nodules,the SUVmax of sevwnty-three malignant nodules was 5.24（1.82,6.99）,the SUVmax of teenty benign nodules was 1.54（0.00,2.82）,the difference of SUVmax between the two groups was statistically significant,P<0.05,The ROC curve was used to analyze the SUVmax of ninty-three cases of nodules,and the SUVmax limit of benign and malignant diagnosis was 3.81,the sensitivity,specificity,accuracy,predictive value of positive results and predictive value of negative results were 54.8%,90.0%,62.4%,95.2%and 35.3%,respectively;The SUVmax of forty-six malignant solid nodules was 7.49（4.18,10.65）,the SUVmax of twenty-seven malignant subsolid nodules was 2.18（0.00,2.90）,the SUVmax of twenty-seven malignant subsolid nodules was 2.18（0.00,2.90）,the difference between the two was statistically significant,P<0.05;There was no significant difference in SUVmax between benign and malignant diagnosis of thirty-six cases of subsolid nodules,P>0.05.The sensitivity,specificity and accuracy of VHRCT in diagnosing SPN were 80.0%,50.0%and 77.8%,The sensitivity,specificity and accuracy of PET/CT in diagnosing SPN were 85.1%,66.7%and 80.6%,respectively,The sensitivity,specificity and accuracy of PET/CT combined with VHRCT in diagnosing SPN were91.3%,69.2%and 83.3%,respectively.ConclusionMalignant solitary pulmonary nodules have higher SUVmax than benign solitary pulmonary nodules,SUVmax3.81 has high specificity,accuracy and positive predictive value in the diagnosis of benign and malignant nodules,the diagnostic value of SUVmaxfor subsolid nodules is limited,however,PET/CT combined with VHRCT has higher sensitivity,specificity and accuracy in differential diagnosis of benign and malignant SPN than PET/CT and VHRCT alone.