The Study Of ¹⁸F-FDG PET/CT In The Qualitative Diagnosis Of Solitary Pulmonary Lesions

ObjectiveTo discuss the relationship between the 18F-FDG PET/CT functional form of solitary pulmonary lesion with benign and malignant lesions, and analyze value of 18F-FDG PET/CT qualitative diagnosis of lesions with different diagnostic scheme and intakes and the main influence factors, to improve the understanding of 18F-FDG PET/CT performance of benign and malignant solitary pulmonary lesion,to further improve the qualitative diagnosis value of 18F-FDG PET/CT in the diagnosis of solitary pulmonary lesions, In order to provide scientific guidance for clinical.MethodsThis was a retrospective analyzed of 18F-FDG PET/CT (American GE Discovery STE 16 row of PET/CT scanners)scans obtained from August 2010 to September 2013 in PET/CT center of Shanxi Tumor Hospital.109 patients with solitary pulmonary lesions (male 67, female 42) were included in this study. According the 18F-FDG PET/CT functional form of solitary pulmonary lesions to grouping, using the chi-square test and Fisher’s exact test method to compare the differences of different functional forms groups between benign and malignant lesions; And comparison in different diagnosis scheme of the qualitative diagnosis value of 18F-FDG PET/CT in the diagnosis of solitary pulmonary lesions, all statistical methods is 0.05 for the inspection level, P<0.05 was considered statistically significant difference.Results1.The pathologic and follow-up results of the solitary pulmonary lesions:In 109 patients with solitary pulmonary lesions,73 cases were malignant,including 52 cases of adenocarcinoma and 13 cases of squamous cell carcinoma,small cell lung cancer in 5,neuroendocrine carcinoma in 3;36 cases were benign, including 6 cases of inflammatory pseudotumor,tuberculosis in 6 cases, lung abscess in 4,isolated fibrous tumor and cartilaginous hamartoma in 1 each, the rest cases of the benign lesions were confirmed by clinical follow-up for more than 2 years,without any change of size or shape.2.The comparison of benign and malignant rate lesions of between different groups. (1) fully intake and not fully intake group (group in addition to fully intake each other all cases) between benign and malignant lesions comparison:fully intake malignant 53 cases in the group,9 cases of benign and the malignant lesions constitute ratio was 85.48%(53/62); Not fully intake of malignant 20 cases,27 cases of benign, malignant lesions in the composition ratio was 42.5%(20/47); Compare the differences between two groups was statistically significant (χ2= 21.87, p< 0.05), fully intake group malignant lesions ratio higher than not fully intake. (2) fully intake, circular intake group and mild group abnormalities merged, no intake and nodular intake of a merger between the three groups of malignant lesions are:fully absorb a group of malignant lesions was 85.48%(53/62); Circular intake with mild intake group 19 cases of malignant and benign in 11 cases, the malignant lesions in the constituent ratio of 63,3%(19/30); Without consuming group and nodular intake malignant in 1 cases,16 cases of benign and malignant lesions composition ratio was 5.9%(1/17); compare the difference between three groups was statistically significant (p< 0.05), fully intake group of malignant> circular intake group and mild group> no intake and nodular intake.3.The comparison of different diagnosis scheme of 18F-FDG PET/CT in the diagnosis of solitary pulmonary lesions results. (1) the diagnostic value SUVave 2.5 as threshold diagnosis for the diagnosis of malignant lesions:in 109 cases of solitary pulmonary lesions in I8F-FDG PET/CT could correctly diagnosis of 79 cases, among which 67 were true positive,24 cases of false positives, true negative 12 cases,6 cases of false negative. The diagnosis accuracy, sensitivity, specific, positive predictive value and negative predictive value was 72.5%(79/109),91.78%(67/73), 33.3%(12/36),73.6%(67/91) and 66.7%(12/18). (2) With SUVave≥2.5, SUVave< 2.5 and focal nodules functional form with a diagnosis of benign intake diagnosis:: PET/CT can correctly diagnosis of 87 cases, among which 67 were true positive and false positive in 16 cases, true negative 20 cases, false negatives in 6 cases. The diagnosis accuracy, sensitivity, specific, positive predictive value and negative predictive value was 79.8%(87/79),91.7%(67/73),55.6%(20/36), there was no statistically significant difference (χ2= 1.22, p= 0.269> 0.05) of the diagnosis accuracy between the two groups. (3) the diagnostic if remove circular intake and mild intake group cases (2) as the standard:PET/CT can correctly diagnosis of 68 cases, the diagnostic accuracy was 86.0%, there was a statistically significant difference (χ2= 4.96, p= 4.96< 0.05), the diagnostic accurate rate is higher than the pure application of SUVave> 2.5.Conclusion1.Intake morphological classification method is a feasible diagnosis method of solitary pulmonary lesions.2.Much Focal uptake, mild uptake is the main reasons of produced false positive and false negative of SUV method.