Frequently mutated genes in predicting the relapse of stage I lung adenocarcinoma.

PURPOSE

Approximately, 45-65% stage I non-small cell lung cancer (NSCLC) patients with surgical resection relapse within 5 years. Therefore, it is urgent to identify the predictors involved in the relapse of stage I NSCLC.

METHODS/PATIENTS: Targeted sequencing was used to examine the mutation of tumor tissues and matched adjacent normal tissues from 35 patients with stage I lung adenocarcinoma (LUAD). Then, tissue microarrays containing tumor tissues from 149 stage I LUAD patients were used to assess protein expression of frequently mutated genes by immunohistochemistry. COX regression model was used to evaluate the impacts of frequently mutated genes and their protein expression on relapse-free survival (RFS) in stage I LUAD.

RESULTS AND CONCLUSIONS

Three hundred and twenty-nine non-synonymous somatic variants were identified in 161 genes among these 35 patients. EGFR, TP53, LRP1B, RBM10, KRAS, NTRK3, RB1, ALK, APC, FAT2, KEAP1, MED12 and MLL3 were described as frequently mutated genes with prevalence more than 10%. Patients harboring KRAS mutation had more relapse in 1 year after surgical resection. For the expression of these frequently mutated genes in 149 stage I patients, multivariate Cox regression analyses showed that the expression of RBM10 was positively associated with RFS in all patients (HR 0.40, 95% CI 0.15-1.0, p = 0.052), and the expression of APC was negative associated with RFS in patients with EGFR mutations (HR 3.10, 95% CI 1.54-6.26, p = 0.002). Stage I LUAD patients with KRAS mutation or low RBM10 expression are inclined to receive more positive intervention rather than just disease surveillance.