Lung cancer is the second-most commonly diagnosed cancer and the leading cause of cancer death worldwide. The most common histological type is non-small-cell lung cancer, accounting for 85% of all lung cancer cases. About one out of three new cases of non-small-cell lung cancer are diagnosed at a locally advanced stage—mainly stage III—consisting of a widely heterogeneous group of patients presenting significant differences in terms of tumor volume, local diffusion, and lymph nodal involvement. Stage III NSCLC therapy is based on the pivotal role of multimodal treatment, including surgery, radiotherapy, and a wide-ranging option of systemic treatments. Radical surgery is indicated in the case of hilar lymphnodal involvement or single station mediastinal ipsilateral involvement, possibly after neoadjuvant chemotherapy; the best appropriate treatment for multistation mediastinal lymph node involvement still represents a matter of debate. Although the main scope of treatments in this setting is potentially curative, the overall survival rates are still poor, ranging from 36% to 26% and 13% in stages IIIA, IIIB, and IIIC, respectively. The aim of this article is to provide an up-to-date, comprehensive overview of the state-of-the-art treatments for stage III non-small-cell lung cancer.

Liquid biopsy has emerged as an alternative source of nucleic acids for the management of Epidermal Growth Factor Receptor (EGFR)-mutant non-Small Cell Lung Cancer (NSCLC). The use of circulating cell-free DNA (cfDNA) has been recently introduced in clinical practice, resulting in the improvement of the identification of druggable EGFR mutations for the diagnosis and monitoring of response to targeted therapy. EGFR-dependent (T790M and C797S mutations) and independent (Mesenchymal Epithelial Transition [MET] gene amplification, Kirsten Rat Sarcoma [KRAS], Phosphatidyl-Inositol 4,5-bisphosphate 3-Kinase Catalytic subunit Alpha isoform [PI3KCA], and RAF murine sarcoma viral oncogene homolog B1 [BRAF] gene mutations) mechanisms of resistance to EGFR tyrosine kinase inhibitors (TKIs) have been evaluated in plasma samples from NSCLC patients using highly sensitive methods (i.e., digital droplet PCR, Next Generation Sequencing), allowing for the switch to other therapies. Therefore, liquid biopsy is a non-invasive method able to detect the molecular dynamic changes that occur under the pressure of treatment, and to capture tumor heterogeneity more efficiently than is allowed by tissue biopsy. This review addresses how liquid biopsy may be used to guide the choice of treatment strategy in EGFR-mutant NSCLC.

MET-based resistance following osimertinib treatment for epidermal growth factor receptor (EGFR)-mutated advanced non-small cell lung cancer (NSCLC) is common. We report the primary analysis of the phase II SAVANNAH study (NCT03778229) evaluating savolitinib plus osimertinib in this setting. Patients had EGFR-mutated, advanced NSCLC with MET overexpression and/or amplification. MET cut-offs were initially MET immunohistochemistry (IHC)3+/≥50% (3+ intensity in ≥50% of tumor cells) and/or FISH5+ (≥5 MET gene copies or MET/chromosome 7 centromere ratio ≥2), and increased to MET IHC3+/≥90% and/or FISH10+ after a preliminary analysis. Patients received oral savolitinib [300 mg twice daily (b.i.d.) or once daily (o.d.), or 600 mg o.d.] plus osimertinib 80 mg o.d., or savolitinib 300 mg b.i.d. plus placebo. A primary endpoint was investigator-assessed objective response rate (ORR) in patients with progression on first-line osimertinib and MET IHC3+/≥90% and/or FISH10+ status receiving savolitinib 300 mg b.i.d. plus osimertinib (primary efficacy population). Safety was analyzed in all patients receiving savolitinib plus osimertinib. Of the 365 patients treated, 341 received savolitinib plus osimertinib, with 80 of these included in the primary efficacy population. Investigator-assessed confirmed ORR in the primary efficacy population was 56.3% [95% confidence interval (CI) 44.7% to 67.3%]; the median duration of response (mDoR) was 7.1 months (95% CI 5.6-9.6 months); the median progression-free survival (PFS) was 7.4 months (95% CI 5.5-7.6 months). Blinded independent central review was consistent: confirmed ORR 55.0% (95% CI 43.5% to 66.2%); mDoR 9.9 months (95% CI 6.0-13.7 months); median PFS 7.5 months (95% CI 6.4-11.3 months). The most common any grade adverse events in patients receiving savolitinib plus osimertinib were peripheral edema (46.0%), nausea (40.5%), and diarrhea (23.2%). Savolitinib 300 mg b.i.d. plus osimertinib demonstrated high, clinically meaningful and durable responses in patients with EGFR-mutated, advanced NSCLC with MET IHC3+/≥90% and/or FISH10+ status following progression on first-line osimertinib. The combination was well tolerated and may provide a new oral targeted treatment approach in this setting.

Compound epidermal growth factor receptor (EGFR) mutations represent a heterogeneous subgroup of non-small cell lung cancer (NSCLC) patients with uncommon EGFR mutations. We conducted a systematic review to investigate the available data on this patients’ subgroup. Overall, we found a high heterogeneity in the incidence of compound mutations (4–26% of total EGFR mutant cases), which is dependent on the different testing methods adopted and the specific mutations considered. In addition, the relative incidence of distinct compound subclasses identified is reported with extreme variability in different studies. Preclinical and clinical data, excluding de novoEGFR exon 20 p.T790M compound mutations, show good responses with EGFR tyrosine kinase inhibitors (TKIs) (combined common mutations: response rate (RR) ≥ 75% with either first- or second-generation TKIs; combined common plus uncommon: RR 40–80% and 100% with first-generation TKIs and afatinib, respectively; combined uncommon: RR 20–70%, ~80% and ~75% with first-generation TKIs, afatinib and osimertinib, respectively). Overall, data are consistent in supporting the use of EGFR TKIs in treating compound EGFR mutations, taking into account different sensitivity profile of accompanying EGFR mutations for selecting the most adequate EGFR TKI for individual patients.

Tyrosine kinase inhibitors (TKIs) revolutionized the treatment of patients with advanced or metastatic non-small cell lung cancer (NSCLC) harboring most driver gene alterations. Starting from the first generation, research rapidly moved to the development of newer, more selective generations of TKIs, obtaining improved results in terms of disease control and survival. However, the use of novel generations of TKIs is not without limitations. We reviewed the main results obtained, as well as the ongoing clinical trials with TKIs in oncogene-addicted NSCLC, together with the biology underlying their potential strengths and limitations. Across driver gene alterations, novel generations of TKIs allowed delayed resistance, prolonged survival, and improved brain penetration compared to previous generations, although with different toxicity profiles, that generally moved their use from further lines to the front-line treatment. However, the anticipated positioning of novel generation TKIs leads to abolishing the possibility of TKI treatment sequencing and any role of previous generations. In addition, under the selective pressure of such more potent drugs, resistant clones emerge harboring more complex and hard-to-target resistance mechanisms. Deeper knowledge of tumor biology and drug properties will help identify new strategies, including combinatorial treatments, to continue improving results in patients with oncogene-addicted NSCLC.