ProSpecTive sAmpling in dRiver muTation Pulmonary Oncology Patients on Tyrosine Kinase Inhibitors (START-TKI)

This is an observational study in pulmonary oncology patients treated with TKI. Ideally before start of therapy, at week 4, 8 12, and then every 4-8 weeks (following the standard of care clinical pathways local guidelines) extra tubes of blood will be collected during blood withdrawal planned for standard-of-care. When a TKI switch takes place, patients receive a new study number and the blood collection will be continued following standard-of-care. Sampling will be performed during steady-state in working hours before next ingestion of TKI (the regular morning dose will need to be postponed until after blood withdrawal).

The moment of blood withdrawal after start of therapy and after last dosage of TKI will be registered.

At the time of progression the current standard of care is to perform a rebiopsy, to identify the resistance mechanism and determine the next appropriate systemic therapy for a patient. Some mechanisms can only be determined on a biopsy specimen (e.g. transformation to SCLC, MET amplification FISH). This study is observational and will not interfere with the current standard practice, therefore the treating physician is free to determine the indication for and possibility of a rebiopsy. However, when a biopsy is taken as standard of care, we will also draw an extra blood sample on the day of the biopsy (preferably during standard preprocedural coagulation status laboratory investigations) and use a portion of the biopsy for a fresh frozen specimen, as evolving molecular investigations (like RNA analysis) often need fresh non-fixed material to obtain reliable results.

Four to five core biopsies will be obtained for further analysis. Half of the obtained biopsy material will be stored in formalin according to local standard procedures, while the other half will be fresh frozen according to local standard procedures and stored for further analysis.

When the treating physician needs to take additional tissue or liquid (e.g. pleural fluid, liquor) for investigations following standard-of-care protocols, we would like to perform additional molecular and/or pharmacokinetic analysis on the residual material when applicable.

• Time to progression or death under treatment with small molecule kinase inhibitor [Time frame: 10 years]
• Overall survival [Time frame: 10 years]
• Pharmacokinetics of intratumoral small molecule kinase inhibitors [Time frame: 10 years]
• Correlation of mutation status in blood to (re)biopsy specimen results performed for standard-of-care. [Time frame: 10 years]
• Correlation between the BMI of the patient and mean concentration of the small molecule kinase inhibitor [Time frame: 10 years]
• Correlation between smoking status of the patients and mean concentration of the small molecule kinase inhibitor [Time frame: 10 years]