In part three of an insight disease-specific oncology series focused on lung cancer, the group answers the important question of: What do you do when performing a biopsy on a suspected metastatic lesion? The question specifically pertains to non-small cell lung cancer (NSCLC). Once the diagnosis of NSCLC is confirmed, and it’s specific histology is pinpointed, a workup should be used to determine the type of chemotherapy the affected patient should receive. Moreover, among other topics, the group detailed the importance of protein, and molecular testing in NSCLC, the differentiation between prognostic and predictive biomarkers, and whether or not “liquid biopsy” can be used to discern if the cancer has relapsed.