Characteristics and Outcomes of Patients with Lung Cancer Harboring Multiple Molecular Alterations: Results from the IFCT Study Biomarkers France

Introduction Little is known about the prevalence, prognosis, and response to treatment of advanced NSCLC harboring multiple genomic alterations. Methods The French Biomarkers France database, which includes 17,664 patients, was used. The prevalence of multiple alterations, their associations, their impact on prognosis (overall survival [OS]), and their response to targeted or conventional treatments (progression-free survival [PFS] and objective response rate) were assessed and compared with those of patients harboring single or no mutation. Results We identified 162 patients (0.9%) with double alterations and three with triple mutations. Multiple molecular alterations preferentially involved KRAS (67.3%), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha gene (PIK3CA) (53.3%), and EGFR (42.4%). Patients with multiple alterations were more likely to be male (56.4%), be never-smokers (25.8 versus 34.7%, p < 0.001), and exhibit adenocarcinomas (83.6%). OS did not differ between single and multiple alterations. Patients with EGFR/KRAS and EGFR/PIK3CA mutations experienced worse PFS than did patients with only EGFR mutations (7.1 and 7.1 versus 14.9 months, p = 0.02 and 0.002, respectively). Concomitant mutations in patients harboring anaplastic lymphoma receptor tyrosine kinase gene (ALK) rearrangement bore little impact on OS (17.7 versus 20.3 months, p = 0.57) or PFS (10.3 versus 12.1 months, p = 0.93). Patients harboring KRAS mutations plus another alteration had an OS time (13.4 versus 11.2 months, p = 0.28), PFS time (6.4 versus 7.2 months, p = 0.78), and objective response rate under first-line chemotherapy (41.7% versus 37.2%) similar to those of patients harboring KRAS mutations only. Conclusions With almost 1% of patients harboring multiple alterations, the dogma of mutually exclusive mutations should be reconsidered. Although double mutations do not decrease OS, they do alter PFS under first-line treatment for patients with EGFR mutations. Among limited numbers of patients, therapies targeting the dominant oncogene seem to usually remain active.