Genomic comparisons between different radiological features in ground glass nodules under 20 mm in diameter.

Abstract

e13664 Background: Radiological features still matters in the management of ground glass nodules (GGNs). The 20 mm in maximum diameter and consolidation tumor ratio (CTR) under 0.5 are pivotal indexes from the lobectomy to segmentectomy decision. However, the feasibility of limited resection remains controversial. Understanding the relationship between genomic characteristics and radiological features of GGNs will provide critical insights to theoretical basis of surgical method decision and expand a novel perspective to risk-stratify patients. Methods: In total, 297 surgically resected GGNs (≤ 20 mm in maximum diameter) were consecutively collected in the study. The summarized radiological features are shown (Table). In order to obtain their comprehensive genomic profiling, these tumor samples were performed using customized panels of 1021 genes. Fisher's exact test, Mann Whitney test and Kruskal-Wallis test were used for statistical analysis. Results: Higher TMB was found in subgroups with the maximum diameter > 10 mm, the volume > 0.40 mL, the CT value > -500 HU, and the mass > 200 mg ( p < 0.05). However, TMB was not associated with the increase of CTR. These data suggested that enlarged nodules occurred with increased mutation events. EGFR, RET, TP53 and RBM10 mutations were significantly enriched in groups with maximum diameter > 10 mm, volume > 0.40 mL, and mass > 0.200 g ( p < 0.05), and significant enrichment in p53-pathway and Myc-pathway were also found ( q < 0.05). ERBB2 and BRAF mutations were significantly enriched in the subgroups with maximum diameter ≤ 10 mm, volume ≤ 0.40 mL, or mass ≤ 0.200 g ( p < 0.05). As compared to the cohort of CTR ≤ 0.5 in all nodules, mutation frequencies of EGFR, RBM10 were similar, those of RET, ALK and TP53 were relatively higher ( p < 0.05), and that of ERBB2 was lower ( p = 1.7×10−5) in the cohort of CTR > 0.5. Conclusions: Our study provides the comprehensive description of the mutational landscape and radio-genomic features of GGNs under 20 mm in diameter. [Table: see text]