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Introduction: Mutated tumor suppressor genes (TSG) such as TP53, STK11, and MGA are widely-reported. We hypothesized the presence of single mutation or co-occurring mutations in these specific genes may represent a significant therapeutic target for lung adenocarcinoma.Methods: We sequenced lung adenocarcinoma samples from 677 East-Asian patients, combined them with those from cBioPortal public database (including TCGA) and performed a comparative analysis between Asian and Caucasian populations.Results: East-Asian lung adenocarcinomas presented distinct driver-mutational distribution compared to that of Caucasians (79% vs 56%, p < 0.001). Similar results were observed in TSG mutations of TP53 (35% vs 46%, p = 0.150), STK11 (4% vs 17%, p = 0.006) and MGA (10% vs 4%, p = 0.166). Compared with none-mutational cases, the patients harboring TSG mutations are more likely to be male (p = 0.009), smokers (p < 0.001), and more advanced disease (p = 0.004). In addition, the TSG-mutated tumors had poorer differentiation (p < 0.001), and more likely to be solid or micropapillary-predominant adenocarcinomas (p < 0.001). Survival analysis showed that both overall survival (OS, p < 0.001) and post-recurrence survival (PRS, p < 0.001) became worse with the accumulation of TSG mutations. However, the prognostic variety was not found in Caucasian patients. Moreover, multivariate analysis proved the accumulation of TSG mutations independently predicts both unfavorable OS (HR = 0.435, 95% CI 0.245-0.774, p = 0.005) and PRS (HR = 0.491, 95% CI 0.269-0.894, p = 0.020) in East-Asian patients, adjusting all other survival-associated factors.Conclusions: Co-occurring mutations of specific TSGs define unfavorable subgroups of lung adenocarcinoma, implying that the tumor promotion mechanisms contribute to the heterogeneity in tumor evolution. However, the Caucasian population did not show the same results, providing insights into the molecular basis underlying the striking racial disparities of this disease and evidence for different gene-panel designs for different population in the purpose of targeted therapy. [ABSTRACT FROM AUTHOR]

Introduction: Evidence shows that exon 19 deletions (19del) and exon 21 Leu858Arg point mutation (L858R) of EGFR are different in response to EGFR tyrosine kinase inhibitor (EGFR-TKI) therapy in advanced lung cancers. However, the impact of the two mutational types in the early stage lung adenocarcinoma is unknown. Methods: We enrolled consecutive patients with operable adenocarcinoma which harbored 19del or L858R to investigate the clinicopathologic characteristics and prognostic outcomes. Results: Between 2008 and 2013, a total of 607 patients with 19del (47.9%) or L858R (52.1%) were included in this study. Clinicopathologic and disease-associated factors were well-balanced between 19del and L858R patients. Both recurrence-free survival (5-year RFS: 37.9% vs. 42.9%, p = 0.075) and overall survival (5-year OS: 64.7% vs. 60.7%, p = 0.741) were similar between the two groups. After relapse, 19del was associated with a better post-recurrence survival (PRS) than L858R ( p = 0.016). Multivariate analysis demonstrated that mutational types (HR = 1.521, 95% CI: 1.106-2.093, p = 0.01) and tyrosine kinase inhibitors (TKI) use after recurrence (HR = 0.422, 95% CI: 0.301-0.592, p < 0.001) were independent predictors of PRS. The 19del and L858R patients were similar regarding recurrent patterns, except on pleural/chest wall metastasis (26.0% vs. 12.2%, p = 0.007). Conclusions: Patients with the early stage lung adenocarcinoma harboring either 19del or L858R share similar RFS and OS. After recurrence, both could benefit from TKI therapy without the need for a second biopsy, but 19del seemed to be associated with better PRS. [ABSTRACT FROM AUTHOR]