In non-squamous advanced NSCLC, 5 biomarkers should be tested in the initial biopsy to base the first line treatment decision: EGFR, ALK, ROS-1, BRAF and PD-L1.
When it hasn't been done at baseline, Solange Peters says it is still important to search for these biomarkers to make a treatment decision after progression.
When an initial biopsy results are available, at progression it is not mandatory to re-test. However, in case more targeted therapies are available at the clinic or for clinical research purposes if rare mutations are found, the second biopsy may give valuable information to decide on a second or third line treatment, especially when an oncogenic driver has been identified at baseline.