Updated Frequency of EGFR and KRAS Mutations in NonSmall-Cell Lung Cancer in Latin America: The Latin-American Consortium for the Investigation of Lung Cancer (CLICaP)

J Thorac Oncol. 2015 May;10(5):838-843. doi: 10.1097/JTO.0000000000000481.

Abstract

Introduction: Previously, we reported the frequency of epidermal growth factor receptor (EGFR) and KRAS mutations in nonsmall-cell lung cancer (NSCLC) patients in Latin America. The EGFR mutation frequency was found between Asian (40%) and Caucasian (15%) populations. Here, we report the updated distribution of NSCLC mutations.

Methods: A total of 5738 samples from NSCLC patients from Argentina (1713), Mexico (1417), Colombia (1939), Peru (393), Panama (174), and Costa Rica (102) were genotyped for EGFR and KRAS.

Results: The median patient age was 62.2 ± 12.3 years; 53.5% were women, 46.7% had a history of smoking, and 95.2% had adenocarcinoma histology. The frequency of EGFR mutations was 26.0% (95% confidence interval [CI], 24.9-27.1; Argentina, 14.4% [12.8-15.6]; México, 34.3% [31.9-36.7]; Colombia, 24.7% [22.8-26.6]; Peru, 51.1% [46.2-55.9]; Panamá, 27.3 [20.7-33.9]; and Costa Rica, 31.4% [22.4-40.4]). The frequency of KRAS mutations was 14.0% (9.1-18.9). In patients with adenocarcinoma, EGFR mutations were independently associated with gender (30.7% females vs. 18.4% males; p < 0.001), nonsmoker status (27.4% vs. 17.1%, p < 0.001), ethnicity (mestizo/indigenous, 35.3% vs. Caucasian, 13.7%, p < 0.001), and the absence of KRAS mutation (38.1% vs. 4.7%; p < 0.001). The overall response rate to EGFR tyrosine kinase inhibitors was 60.6% (95% CI, 52-69), with a median progression-free survival and overall survival of 15.9 (95% CI, 12.420.6) and 32 months (95% CI, 26.5-37.6), respectively.

Conclusion: Our findings support the genetic heterogeneity of NSCLC in Latin America, confirming that the frequency of EGFR mutations is intermediate between that observed in the Asian and Caucasian populations.

MeSH terms

  • Adenocarcinoma / genetics*
  • Adenocarcinoma / pathology
  • Aged
  • American Native Continental Ancestry Group / genetics
  • Argentina
  • Carcinoma, Non-Small-Cell Lung / drug therapy
  • Carcinoma, Non-Small-Cell Lung / genetics*
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Colombia
  • Costa Rica
  • Disease-Free Survival
  • ErbB Receptors / antagonists & inhibitors
  • ErbB Receptors / genetics*
  • European Continental Ancestry Group / genetics
  • Female
  • Genetic Heterogeneity
  • Humans
  • Lung Neoplasms / drug therapy
  • Lung Neoplasms / genetics*
  • Lung Neoplasms / pathology
  • Male
  • Mexico
  • Middle Aged
  • Mutation Rate*
  • Panama
  • Peru
  • Protein Kinase Inhibitors / therapeutic use
  • Proto-Oncogene Proteins p21(ras) / genetics*
  • Sex Factors
  • Smoking / genetics
  • Survival Rate

Substances

  • KRAS protein, human
  • Protein Kinase Inhibitors
  • ErbB Receptors
  • Proto-Oncogene Proteins p21(ras)