An international epidemiological analysis of young patients with non-small cell lung cancer (AduJov-CLICaP)

Background: A proportion of patients with NSCLC is diagnosed at 40 years or younger. These patients tend to be never-smokers, usually present with stage IV adenocarcinoma, and have somatic genomic alterations. Few studies have documented and analyzed epidemiological characteristics of this population. Materials and methods: We performed an international epidemiological analysis of 389 young patients with NSCLC. Data was collected from centers participating in the Latin American Consortium for Lung Cancer Research (AduJov-CLICaP). Patients were identified and data was retrospectively collected from different Latin American countries and Canada (Argentina = 6, Canada = 19, Colombia = 29, Costa Rica = 9, Mexico = 219, Nicaragua = 2, Panama = 19, Peru = 76 and Venezuela = 10). The period of study was from 2012 to 2017. Inclusion criteria were: age 40 years or less and a histologically confirmed NSCLC. Clinical data was obtained, and EGFR mutation status and EML4-ALK translocation were collected. Results: NSCLC patients aged 40 years or less accounted for approximately 4% of the total NSCLC population. Female patients accounted for 54.5%, while median age was of 37 years. Adenocarcinoma accounted for 86.1% (n = 335/389), 72.5% (n = 282/389; unknown = 5) of patients were non-smokers, and 90.3% (n = 351/389) had stage IV disease. Site of metastasis was obtained from 260/351 (unknown = 91) stage IV patients (lung metastasis = 40.0%, CNS metastasis = 35.7%, and bone metastasis = 31.5%). OS for the total population was 17.3 months (95%CI = 13.9-20.7). OS for EGFRm(+) = 31.4 months (95%CI = 11.6-51.3), EGFRm(-) = 14.5 months (95%CI = 11.0-17.9) (p = 0.005). OS for alk(+) = 9.8 months (95%CI = 3.1-16.5) and alk(-) = 5.6months (95%CI = 3.9-7.3) (p = 0.315). Conclusions: Patients aged 40 years or less account for a small but important proportion of NSCLC cases. Younger patients may have different characteristics compared to the older population. EGFRm and EML4-alk translocation frequency is higher than that of the general population.