Large-scale EGFR testing in the blood of unselected advanced NSCLC patients is feasible and can be used to select patients for targeted therapy when testing cannot be done in tissue. The characteristics and clinical outcomes to TKI treatment of the EGFR-mutated patients identified are undistinguishable from those positive in tumor.

Treatment for advanced non-small cell lung cancer (NSCLC) has been significantly improved in recent years with the incorporation of drugs targeting antiangiogenesis and more specifically genomic alterations such as the EGFR mutations and ALK translocations. However, most patients invariably progress and die. The emergence of immune checkpoint inhibitors targeting the pathways involved in tumor-induced immunosuppression have redefined the management of the disease, achieving significant long-lasting responses with manageable safety profiles, regardless of histology. Still, response rates with immunotherapy are deemed suboptimal. Current efforts are focusing on new potential combination strategies with synergistic antitumor activity, using immune checkpoint blockade as a partner for targeted agents. Herein we discuss the available data on the combined use of immunotherapy, including PD-1/PD-L1 and CTLA-4 inhibitors, with EGFR and ALK inhibitors and comment on the current status of immunotherapy plus antiangiogenic drugs for molecularly unselected advanced NSCLC.

Many advanced cases of cancer show central nervous system, pleural, or peritoneal involvement. In this study, we prospectively analyzed if cerebrospinal fluid (CSF), pleural effusion (PE), and/or ascites (ASC) can be used to detect driver mutations and guide treatment decisions. We collected 42 CSF, PE, and ASC samples from advanced non‐small‐cell lung cancer and melanoma patients. Cell‐free DNA (cfDNA) was purified and driver mutations analyzed and quantified by PNA‐Q‐PCR or next‐generation sequencing. All 42 fluid samples were evaluable; clinically relevant mutations were detected in 41 (97.6%). Twenty‐three fluids had paired blood samples, 22 were mutation positive in fluid but only 14 in blood, and the abundance of the mutant alleles was significantly higher in fluids. Of the 34 fluids obtained at progression to different therapies, EGFR resistance mutations were detected in nine and ALK acquired mutations in two. The results of testing of CSF, PE, and ASC were used to guide treatment decisions, such as initiation of osimertinib treatment or selection of specific ALK tyrosine–kinase inhibitors. In conclusion, fluids close to metastatic sites are superior to blood for the detection of relevant mutations and can offer valuable clinical information, particularly in patients progressing to targeted therapies.

No abstract