Abstract
BACKGROUND: Occurrence at a younger age has been demonstrated to be associated with a distinct biology in non-small cell lung cancer. However, genomics and clinical characteristics among younger patients with lung adenocarcinoma remain to be determined. Here we studied the potentially targetable genetic alterations by next-generation sequencing (NGS) assay in young Chinese patients with lung adenocarcinoma. METHODS: Eighty-nine surgically resected lung adenocarcinoma tissue samples from patients aged less than 45 years were collected with informed consent from all patients. Targeted NGS assays were used to identify actionable genetic alterations in the cancer tissues. Additionally, the genomic and clinical pathologic characteristics of 95 patients with lung adenocarcinoma who received NGS testing over the same period were analyzed retrospectively. RESULTS: The frequencies of targetable genetic alterations in 184 patients with lung adenocarcinoma were analyzed by defined age categories, which unveiled a distinctive molecular profile in the younger group, aged less than 45 years. Notably, higher frequency of anaplastic lymphoma kinase (ALK) and human epidermal growth factor receptor 2 (HER2) genetic alterations were associated with young age. However, a reverse trend was observed for kirsten rat sarcoma viral oncogene (KRAS), serine/threonine kinase 11 (STK11) and epidermal growth factor receptor (EGFR) exon 20 mutations, which were more frequently identified in the older group, aged more than 45 years. Furthermore, concurrent EGFR/tumor protein p53 (TP53) mutations were much more prevalent in the younger patients (81.6% vs 44.9%), which might have a poor response to treatment with EGFR-tyrosine kinase inhibitor (EGFR-TKI). CONCLUSIONS: NGS assay revealed a distinctive genetic profile in younger patients with adenocarcinoma. High frequency of concurrent EGFR/TP53 mutations was found in the younger patients, which especially warranted personalized treatment in this population.