EGFR Amplification and Sensitizing Mutations Correlate with Survival in Lung Adenocarcinoma Patients Treated with Erlotinib (MutP-CLICaP)

• Published in: Targeted oncology 2018-10, Vol.13 (5), p.621-629
• Main Authors: Ruiz-Patiño, Alejandro, Castro, Christian David, Ricaurte, Luisa María, Cardona, Andrés F., Rojas, Leonardo, Zatarain-Barrón, Zyanya Lucia, Wills, Beatriz, Reguart, Noemí, Carranza, Hernán, Vargas, Carlos, Otero, Jorge, Corrales, Luis, Martín, Claudio, Archila, Pilar, Rodriguez, July, Avila, Jenny, Bravo, Melissa, Pino, Luis Eduardo, Rosell, Rafael, Arrieta, Oscar
• Format: Article
• Language: English
• Subjects: Biomedicine; Clinical outcomes; Hispanic people; Inhibitor drugs; Lung cancer; Medicine; Medicine & Public Health; Mutation; Oncology; Original Research Article; Targeted cancer therapy
• ISSN: 1776-2596; 1776-260X
• DOI: 10.1007/s11523-018-0594-x

Background Non-small cell lung cancer (NSCLC) has a 5-year survival of 5–16%. Epidermal growth factor receptor ( EGFR ) mutations, in most cases, confer sensitivity to EGFR tyrosine kinase inhibitor (TKI) therapy. Nonetheless, it is still unclear why clinical outcomes vary among patients with identical EGFR mutations. The amplification of the EGFR gene ( EGFR amp) may play a significant role. Objective Compare the complete (CR) and partial response (PR) rates, overall survival (OS), and progression-free survival (PFS) in Hispanic patients with lung adenocarcinoma treated with erlotinib with EGFR mutations (L858R or exon 19 deletion [Del19]) with and without concomitant EGFR amp. Patients and Methods Seventy-two EGFR -positive lung adenocarcinoma patients of Hispanic origin, who underwent first-line treatment with erlotinib, were evaluated for EGFR amp by fluorescence in situ hybridization (FISH). The clinical outcomes were analyzed according to EGFR mutations and EGFR amp status. Results 30.6% of samples showed EGFR amp, more frequently present in patients with Del19 ( p  = 0.05). Patients with EGFR amp had a longer PFS (in months) [(28.5, 95% CI 22.3–34.6) vs. (11.0, 95% CI 8.2–16.7); p  = 0.002] and OS [(37.8, 95% CI 30.9–44.7) vs. (27.1, 95% CI 12.8–41.3); p  = 0.009] than those without. EGFR amp significantly influenced the response to erlotinib ( p  = 0.0001). EGFR amp+/Del19 had a longer OS, 37.8 (95% CI 31.0–44.6), compared to EGFR amp+/L8585R, 27.5 (95% CI 12.4–42.5) ( p