[Predictive role of EGFR mutation status on postoperative prognosis in patients with resected lung adenocarcinomas]

Somatic mutations combined with clinical features can predict the postoperative prognosis of stage IIIA lung adenocarcinoma

Background

Prognostic factors for stage IIIA lung adenocarcinoma (LUAD) are unclear. The current main treatment for stage IIIA LUAD is still controversial. Some Clinicians advocate synchronous chemoradiotherapy as the main treatment for stage IIIA LUAD. In contrast, some clinicians argue that there are still certain patients with stage IIIA LUAD who have a better postoperative prognosis. This study aimed to analyze preoperative factors as well as the association between somatic mutations and prognosis in stage IIIA LUAD [including overall survival (OS) time and the risk of postoperative recurrence].

Methods

This study retrospectively reviewed the data of patients with stage IIIA LUAD who underwent radical resection of lung cancer in the thoracic surgery department of Tianjin Chest Hospital from January 01, 2011 to September 30, 2016. All patients involved in the study provided written informed consent. The associations between OS and DFS and the clinical characteristics as well as somatic mutations of patients were analyzed separately. The Kaplan-Meier method was used for univariate analysis, and survival curves were drawn. Multivariate analysis was performed by the Cox regression model.

Results

For univariate analysis, the prognostic factors of OS were the level of preoperative CYFRA21-1, the number of metastatic lymph node stations (NMLS), maximum tumor diameter, EGFR (epidermal growth factor receptor) classical base mutations, and the number of copies of POLE (polymerase epsilon) mutation (NCPM). Preoperative total protein level, preoperative CYFRA21-1 level, the number of metastatic lymph nodes (NMLN), maximum tumor diameter, the number of mutated genes (NMG) in tumor samples, TP53 mutations, and the number of copies of POLE mutation (NCPM) were associated with disease-free survival (DFS). The multivariate analysis showed that the preoperative CYFRA21-1 level, the number of metastatic lymph node stations (NMLS), and EGFR typical base mutations were independent prognostic factors of OS. The number of mutated genes (NMG), EGFR classical base mutations, preoperative NSE level, maximum tumor diameter, and the number of metastatic lymph node stations (NMLS) were independent prognostic factors for DFS.

Conclusions

The preoperative level of tumor markers, the number of metastatic lymph node stations, and EGFR typical base mutations are important factors for the prognosis of patients with resectable stage IIIA LUAD.

The impact of epidermal growth factor receptor mutations on the prognosis of resected non-small cell lung cancer: a meta-analysis of literatures

BACKGROUND

Epidermal growth factor receptor (EGFR) mutation represents a good response to EGFR-tyrosine kinase inhibitor and an advantageous prognostic factor in advanced-stage non-small cell lung cancer (NSCLC). However, the predictive value of EGFR mutation for prognosis in NSCLC patients after complete surgery, which more reflective of natural process, remains controversial. We sought to examine the predictive value of EGFR mutation in NSCLC. Several studies with small sample sizes have been reported but small studies bring bias especially in a postoperative setting. Therefore, we sought to pool all current evidence to show the true effects.

METHODS

Electronic databases were used to search the relevant articles. Disease-free survival (DFS), which will be less effected by subsequent treatments after recurrence, was the primary endpoint. The DFS between EGFR mutated and wild-type patients were compared focus on stage I patients who are rarely received adjuvant therapy. Besides, the DFS of patients with 19 exon deletion (19del) and 21 exon L858R mutation (L858R) were compared. A random effects model was used.

RESULTS

A total of 19 relevant studies which involved 4,872 cases were enrolled and 2,086 patients were EGFR-mutated. The majority of studies used PCR-based methods to detect EGFR mutations. Through meta-analysis, we observed the DFS of EGFR-mutated patients were similar to wild type patients in overall population (HR 0.93, 95% CI: 0.74 to 1.17). Similar results were observed in stage I subgroup (HR 0.82, 95% CI: 0.50 to 1.33). DFS of 19 del patients were potentially inferior to L858R patients but the difference was not significant (HR 1.38, 95% CI: 0.76 to 2.52).

CONCLUSIONS

There was no significant difference in postoperative DFS between EGFR-mutant patients and wild-type with resected NSCLC. In addition, there is still insufficient evidence to support different postoperative treatment strategies (especially for stage I) for both mutated and wild-type patients. However, 19 del may be a negative factor, which may require more strict management. Thus, we strongly encourage reporting specific prognostic impacts of different mutation types.

Prognostic value of epidermal growth factor receptor mutations in resected non-small cell lung cancer: a systematic review with meta-analysis

BACKGROUND

The prognostic value of epidermal growth factor receptor (EGFR) mutations in resected non-small cell lung cancer (NSCLC) remains controversial. We performed a systematic review with meta-analysis to assess its role.

METHODS

Studies were identified via an electronic search on PubMed, Embase and Cochrane Library databases. Pooled hazard ratio (HR) for disease-free survival (DFS) and overall survival (OS) were calculated for meta-analysis.

RESULTS

There were 16 evaluated studies (n  =  3337) in the meta-analysis. The combined HR evaluating EGFR mutations on disease free survival was 0.96 (95% CI [0.79-1.16] P  =  0.65). The combined HR evaluating EGFR mutations on overall survival was 0.86 (95% CI [0.72-1.04] P  = 0.12). The subgroup analysis based on univariate and multivariate analyses in DFS and OS showed no statistically significant difference. There was also no statistically significant difference in DFS and OS of stage I NSCLC patients.

CONCLUSION

The systematic review with meta-analysis showed that EGFR mutations were not a prognostic factor in patients with surgically resected non-small cell lung cancer. Well designed prospective study is needed to confirm the result.