Purpose: Regarding the controversial investigations characterizing the role of KRAS status for predicting patients' response to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in advanced non-small-cell lung cancer (NSCLC), we conducted a meta-analysis in unselected patients and a further subset analysis in EGFR wild-type advanced NSCLC to get a more accurate evaluation.
Methods: We did systematically searches following the retrieval strategies. The end points were overall survival (OS), progression-free survival (PFS), and overall response rate (ORR).
Results: Twelve prospective intervention trials comprised of 1,859 unselected advanced NSCLC patients were identified. KRAS mutation was associated with shorter OS and PFS [hazard ratio (HR) 2.09, 95 % confidence interval (CI) 1.56-2.80; HR 1.82, 95 % CI 1.50-2.20] and lower ORR (relative ratio 0.25, 95 % CI 0.11-0.59) in unselected advanced NSCLC. After subgroup analysis, the association with survival was strengthened in second- or later-line EGFR-TKIs treatment group, with an HR of 2.45 for OS (95 % CI 1.27-4.74) and 1.86 for PFS (95 % CI 1.51-2.29), while the association with response to EGFR-TKIs became nonsignificant (P = 0.153). Four retrospective studies on the role of KRAS status in EGFR wild-type advanced NSCLC were deemed eligible and presented that KRAS mutation was associated with none of the outcomes in EGFR wild-type patients treated with EGFR-TKIs.
Conclusions: In unselected advanced NSCLC patients, KRAS mutations could be used as a potential negative predictor of clinical benefit from EGFR-TKIs. However, KRAS testing is of limited value to identify patients for EGFR-TKIs when EGFR status is considered.