Clinical and Radiological Features of Synchronous Pure Ground-Glass Nodules Observed Along With Operable Non-Small Cell Lung Cancer

Background: It is common to observe synchronous pure ground-glass nodules (PGN) along with operable primary tumor on initial CT scans while clinical and radiological features of these PGNs remain unclear. Methods: We included patients with primary tumor and PGNs detected between June 2010 and December 2013 retrospectively. The radiographic manifestations of all PGNs, pathologic findings of resected PGNs, and follow-up outcomes of unresected PGNs were analyzed to determine the predictors of malignant PGNs. Results: Overall, 84 PGNs in 71 patients were included, of which 41 were resected at primary surgery and 43 were followed up. In resected group, there were 17 carcinomatous PGNs, 11 atypical adenomatous hyperplasia, and 13 benign lesions. In a follow-up group, 7 out of 43 PGNs grew, out of which four PGNs were diagnosed as adenocarcinoma and the remaining three PGNs were still followed up. In univariate analysis, size (P < 0.001), air bronchogram (P = 0.001), bubble lucency (P = 0.038), and pleural tag (P = 0.004) were the factors for malignant potential of PGNs. Multivariate analysis showed that size was an independent risk factor (P = 0.005), and the cut-off value was 9.4 mm. Conclusions: The initial size and imaging signs may be useful in assessing the malignant potential of synchronous PGNs before surgery. (C) 2016 Wiley Periodicals, Inc.