Indeed, comparison of EGFR p.L858R prevalence in this series (considering each tumour as being from a unique patient) to that in a large cohort of Chinese lung adenocarcinoma patients15 showed no enrichment in this series (6 mutations in 15 tumours (the lymph node was not included) in our study versus 111 mutations in 437 patients in the larger cohort, P=0.23 by Fisher's exact test). The gene discussed is EGFR; the disease is lung adenocarcinoma.