Using Whole Genome Amplification (WGA) of Low-Volume Biopsies to Assess the Prognostic Role of EGFR, KRAS, p53, and CMET Mutations in Advanced-Stage Non-small Cell Lung Cancer (NSCLC)

Background: Progression of non-small cell lung cancer (NSCLC) from early- to late-stage may signify the accumulation of gene mutations. An advanced-stage tumor's mutation profile may also have prognostic value, guiding treatment decisions. Mutation detection of multiple genes is limited by the low amount of deoxyribonucleic acid extracted from low-volume diagnostic lung biopsies. We explored whole genome amplification (WGA) to enable multiple molecular analyses. Methods: Eighty-eight advanced-stage NSCLC patients were enrolled. Their low-volume lung biopsies underwent WGA before direct sequencing for epidermal growth factor receptor ( EGFR ), KRAS (rat sarcoma virus), p53 , and CMET (mesenchymal-epithelial transition factor) mutations. Overall survival impact was examined. Surgically-resected tumors from 133 early-stage NSCLC patients were sequenced for EGFR , KRAS and p53 mutations. We compared the mutation frequencies of both groups. Results: It is feasible for low-volume lung biopsies to undergo WGA for mutational analysis. KRAS and CMET mutations have a deleterious effect on overall survival, hazard ratios 5.05 ( p = 0.009) and 23.65 ( p = 0.005), respectively. EGFR and p53 mutations, however, do not have a survival impact. There also does not seem to be significant differences in the frequency of mutations in EGFR , KRAS , and p53 between early- and advanced-stage disease: 20% versus 24% ( p = 0.48), 29% versus 27% ( p = 0.75), 10% versus 6% ( p = 0.27), respectively. Conclusions: In advanced-stage NSCLC, KRAS , and CMET mutations suggest poor prognosis, whereas EGFR and p53 mutations do not seem to have survival impact. Mutations in EGFR , KRAS and p53 are unlikely to be responsible for the progression of NSCLC from early- to late-stage disease. WGA may be used to expand starting deoxyribonucleic acid from low-volume lung biopsies for further analysis of advanced-stage NSCLC.