Value Of The CT Features Of Ground-glass Nodule For Diagnosing Lung Adenocarcinoma In Early Stage: A Meta Analysis

Objective: The aim of the meta analysis is to systematicly assess the value of CT findings of ground glass nodule(GGN), such as bubble lucency, speculation, lobulation and pleural retraction, for diagnosing lung adenocarcinoma in early stage.Methods: A search in Pub Med, Embase, Medline, SCIE, CNKI, CBM and Wan Fang was performed to retrieve relevant English and Chinese articles respectively. These literatures were about the value of different signs of GGN on the high resolution CT images in differentiating lung invasive lesions from preinvasive lesions in recent years.Criteria for inclusion were established based on validity criteria for diagnostic research,which was published by the Cochrane Methods Group on Screening and Diagnostic. Used Stata 12 software to analyze publication bias and heterogeneity, and to summarize the standardized mean difference(SMD). Meta-disc 1.4 software was used to analyze heterogeneity and threshold effect. The sensitivity, specificity, diagnostic odd ratio(DOR), summary receiver operating characteristic(SROC) curves and the area under the curve(AUC) were calculated to evaluate the diagnostic efficiency.Results: 1.Ten articles were included. Publication bias and heterogeneity existed among all studies. The heterogeneity of qualitative data mainly emerged from the threshold effect.And the random effect model was selected to complete meta analysis. The SMD and its95% confidence interval(95%CI) for the diameter of pure GGN, mixed GGN and the solid component in mixed GGN were 1.05(0.6,1.5), 1.33(0.83,1.82) and 1.33(0.90,1.76),respectively. And 0.86(0.43,1.29)for the density of GGN. Significant difference was found between invasive and preinvasive lesions. 2. The sensitivity and 95% confidence interval(95%CI) for bubble lucency, speculation, lobulation and pleural retraction were0.46(0.40,0.53), 0.40(0.34,0.46), 0.26(0.21,0.32), 0.46(0.40,0.53), respectively.And their specificity and 95 % confidence interval(95%CI) were 0.71(0.64,0.78), 0.81(0.74,0.86),0.87(0.81, 0.92), 0.71(0.64, 0.78), respectively; The diagnostic odd ration and its 95 %confidence interval(95%CI) were 2.16(1.29, 3.61)、2.35(0.85, 6.52)、2.33(1.26, 4.31)、1.53(0.86, 2.74), respectively;The AUC of SROC of lucency and lobulation were 62.07%,53.49%, 71.1%, 52.77%, respectively.Conclusion: Both the density and the size of GGN or the size of solid component in part-solid GGN have significant difference between preinvasive and invasive lesions. The greater the nodule diameter and density are, the higher the degree of malignancy would be.The bubble lucency and lobulated border have moderate diagnostic value, while the spiculated margin and pleural retraction have mild value in distinguishing preinvasive and invasive lesions.