Blood Sample Monitoring of Patients With EGFR Mutated Lung Cancer

In non-small celled lung cancer (NSCLC) 10-15% of the patients harbor a mutation in the tumor's epidermal growth factor receptor (EGFR M+). This receptor is the target for treatment with erlotinib. Identification of EGFR M+ is done on a biopsy, which can be difficult to retrieve. A new blood based test identifies EGFR M+ in plasma, which makes it possible to monitor the level of EGFR M+ in the patient's blood during treatment. This enables both a closer monitoring of the treatment with erlotinib and a closer study of the resistance mechanisms that almost inevitably develop during treatment. A pilot study demonstrated that the quantity of EGFR M+ in plasma correlates to the response to treatment and might be used to predict disease progression. Patients with EGFR M+ NSCLC referred to a participating oncology department may be enrolled in the project. The investigators expect to include 250 patients over a four-year period. Patients will receive standard treatment and follow up. Standard 1st line treatment for patients with metastatic disease is tyrosine kinase inhibitors (TKI) eg. erlotinib. A biopsy and blood sample will be retrieved before treatment with is initiated. The patient will be monitored prospectively with blood samples every 3rd-6th week both during erlotinib treatment, subsequent lines of treatment and treatment intermissions. The blood samples are analyzed for subtypes of EGFR M+ both sensitizing mutations and mutations known to drive resistance to erlotinib treatment. In the event of occurring resistance mutations or unexpected increase in quantity of sensitizing mutations clinical action will be taken; initially in the form of additional scans searching for signs of disease progression. Clinical data will be retrieved from the patient's medical journal. Patients are followed until death or at least 24 months after inclusion. Any excess biological material will be stored for up to 15 years in a bio bank for future research purposes. We expect our re