In NSCLC, KRAS mutations occur in up to 30% of all cases, most frequently at codon 12 and 13. KRAS mutations have been linked to adenocarcinoma histology, positive smoking history, and Caucasian ethnicity, although differences have been described across KRAS mutational variants subtypes. KRAS mutations often concur with other molecular alterations, notably TP53, STK11, and KEAP1, which could play an important role in treatment efficacy and patient outcomes. For many years, KRAS mutations have been considered undruggable mainly due to a high toxicity profile and low specificity of compounds. Sotorasib and adagrasib are novel KRAS inhibitors that recently gained FDA approval for pre-treated KRAS mutant NSCLC patients, and other molecules such as GDC-6036 are currently being investigated with promising results. Despite their approval, the efficacy of these drugs is lower than expected and progression among responders has been reported. Mechanisms of acquired resistance to anti-KRAS molecules typically involves either on target secondary mutations (e.g., G12, G13, Q61H, R68S, H95, Y96C, V8L) or off-target alterations. Ongoing trials are currently evaluating strategies for implementing efficacy and overcoming acquired resistance to these compounds. Finally, the efficacy of immune-checkpoint inhibitors still needs to be completely assessed and responses to anti-PD-1/PD-L1 agents may strongly depend on concomitant mutations.
Lung cancer is the leading cause of cancer deaths in the world. Surgery is the most potentially curative therapeutic option for patients with early-stage non-small cell lung cancer (NSCLC). The five-year survival for these patients remains poor and variable, depending on the stage of disease at diagnosis, and the risk of recurrence following tumor resection is high. During the last 20 years, there has been a modest improvement in the therapeutic strategies for resectable NSCLC. Immune checkpoint inhibitors (ICIs), alone or in combination with chemotherapy, have become the cornerstone for the treatment of metastatic NSCLC patients. Recently, their clinical development has been shifted in the neoadjuvant and adjuvant settings where they have demonstrated remarkable efficacy, leading to improved clinical outcomes. Based on the positive results from phase III trials, ICIs have become a therapeutic option in neoadjuvant and adjuvant settings. On October 2021 the Food and Drug Administration (FDA) approved atezolizumab as an adjuvant treatment following surgery and platinum-based chemotherapy for patients with NSCLC whose tumors express PD-L1 ≥ 1%. In March 2022, nivolumab in combination with platinum-doublet chemotherapy was approved for adult patients with resectable NSCLC in the neoadjuvant setting. The current review provides an updated overview of the clinical trials exploring the role of immunotherapy in patients with early-stage NSCLC, focusing on the biological rationale for their use in the perioperative setting. We will also discuss the role of potential predictive biomarkers to personalize therapy and optimize the incorporation of immunotherapy into the multimodality management of stage I-III NSCLC.
The ability to identify the broadest range of targetable gene fusions is crucial to facilitate personalized therapy selection for advanced lung adenocarcinoma (LuADs) patients harboring targetable receptor tyrosine kinase (RTK) genomic alterations. In order to evaluate the most effective testing approach for LuAD targetable gene fusion detection, we analyzed 210 NSCLC selected clinical samples, comparing in situ (Fluorescence In Situ Hybridization, FISH, and ImmunoHistoChemistry, IHC) and molecular (targeted RNA Next-Generation Sequencing, NGS, and RealTime-PCR, RT-PCR) approaches. The overall concordance among these methods was high (>90%), and targeted RNA NGS was confirmed to be the most efficient technique for gene fusion identification in clinical practice, allowing the simultaneous analysis of a large set of genomic rearrangements at the RNA level. However, we observed that FISH was useful to detect targetable fusions in those samples with inadequate tissue material for molecular testing as well as in those few cases whose fusions were not identified by the RNA NGS panel. We conclude that the targeted RNA NGS analysis of LuADs allows accurate RTK fusion detection; nevertheless, standard methods such as FISH should not be dismissed, as they can crucially contribute to the completion of the molecular characterization of LuADs and, most importantly, the identification of patients as candidates for targeted therapies.
1 September 2021 in Critical Reviews in Oncology/Hematology