EGFR/KRAS mutations in African Americans (AA) versus Caucasians (CA) in patients with NSCLC: A comparative analysis of the South Carolina experience.

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e18018 Background: AAs with NSCLC has inferior survival compared to CAs (Abidoye, Nature 2007). We sought to discern whether differences in incidence of EGFR or KRAS mutations between races could partly explain these differences. Methods: Pts with NSCLC who were seen at the Hollings Cancer Center (HCC) and underwent EGFR and KRAS mutation testing in 2010 were included. Microdissected formalin-fixed paraffin-embedded tumors from 89 patients with NSCLC were analyzed for EGFR/KRAS mutations by allele-specific PCR. Data were compared with previously reported experiences from Memorial Sloan Kettering Cancer Center (MSKCC), (Reinersman et al), Case Western Reserve (CWR), (Leidner et al) and Louisiana State University Health Sciences Center (LSU) (Hunt et al). We estimated the percentage of EGFR+ and KRAS+ AA and CA subjects using exact binomial confidence intervals, and compared proportions using Fisher’s exact test. Aggregate estimates were obtained using inverse variance-weighting and random-effects modeling to account for study heterogeneity. Results: Of the 89 pts, 63 were CAs and 26 were AAs. In AA population, 24/26 pts had successful EGFR and KRAS analysis. In the CA population 59/63 pts and 61/63 pts had successful EGFR and KRAS testing, respectively. Data are in the table below. A weighted aggregate are also compiled. Conclusions: Overall, the incidence of EGFR and KRAS mutations were similar for AAs and CAs. The observed differences in survival between AAs and CAs cannot be explained by differences in the molecular entities examined. Detailed demographic and survival data will be provided at the meeting. EGFR Status KRAS Status N+/total N (%; 95% CI) N+/total N (%; 95% CI) p N+/total N (%; 95% CI) N+/total N (%; 95% CI) p AA CA AA CA HCC 2/24 (8; 1, 27) 10/59 (17; 8, 29) 0.49 6/24 (25; 10, 47) 16/61 (26; 16, 39) >0.99 MSKCC 23/121 (19; 12, 27) 61/476 (13;10, 16) 0.11 21/121 (17; 11, 25) 125/476 (26; 22, 30) 0.04 CWR 1/53 (2; 0, 10) 15/89 (17; 10, 26) 0.005 12/53 (23; 12, 36) 16/76 (21; 13, 32) 0.83 LSU NR NR 22/60 (37; 25, 50) 10/51 (20; 10, 33) 0.06 Aggregate 26/198 (10; 0, 21) 86/624 (14; 11, 16) 0.51 61/258 (25; 16, 33) 167/664 (25; 22, 28) 0.92 Abbreviation: CI, confidence intervals; NR, not reported.