Natural Disease History, Outcomes, and Co-mutations in a Series of Patients With BRAF-Mutated Non-small-cell Lung Cancer

Genomic Landscape of NSCLC in the Republic of Ireland

Introduction

The identification of genomic "targets" through next-generation sequencing (NGS) of patient's NSCLC tumors has resulted in a rapid expansion of targeted treatment options for selected patients. This retrospective study aims to identify the proportion of patients with advanced NSCLC in the Republic of Ireland whose tumors harbor actionable genomic alterations through broad NGS panel testing.

Methods

Institutional review board approval was obtained before study initiation. Patients with NSCLC whose tumors underwent genomic testing through the largest available NGS panel at a nationally funded Cancer Molecular Diagnostics laboratory (St. James's Hospital) between June 2017 and June 2022 were identified. Patient demographics and tumor-related data were collected by retrospective review from all cancer centers in Ireland, referring to the Cancer Molecular Diagnostics laboratory. A total of 203 (9%) tumor samples were excluded due to insufficient neoplastic cell content. Genomic data were collected through retrospective search of Ion Reporter software. The spectrum and proportion of patients with oncogenic driver mutations were evaluated using descriptive statistics (SPSS version 29.0).

Results

In total, 2052 patients were identified. Patients were referred from 23 different hospital sites and all four geographic regions (Leinster = 1091, 53%; Munster = 763, 37.2%; Connacht = 191, 9.3%; Ulster = 7, 0.3%). Median age was 69 (range: 26-94) years; 53% were male. The most common tumor histologic subtype was adenocarcinoma (77%, n = 1577). An actionable genomic alteration was identified in 1099 cases (53%), the most common of which was KRAS (n = 657, 32%). Less frequently, NSCLC tumors harbored the following: MET exon 14 skipping (n = 53, 2.6%), MET amplification (n = 26, 1.3%), EGFR (n = 181, 8.8%), HER2 (n = 35, 1.7%), and BRAF (n = 72, 3.5%) mutations. Fusions were detected in 76 patients (3.7%) including ALK (n = 44, 58%), RET (n = 11, 14.5%), ROS1 (n = 16, 21%), and FGFR3 (n = 5, 6.6%), whereas no NTRK fusion was identified. Co-alterations were detected in 114 patients (5.6%), the most common of which was KRAS/PIK3CA (n = 19, 17%), EGFR/PIK3CA (n = 10, 8.5%), and KRAS/IDH1 (n = 9, 8%). Other co-alterations of interest identified included KRAS G12A/ROS1 fusion (n = 1) and KRAS G12C/BRAF G469A (n = 2).

Conclusions

This is the first retrospective study to comprehensively characterize the genomic landscape of NSCLC in Ireland, using the broadest available NGS panel. Actionable alterations were identified in 53.4% of the patients, and KRAS was the most common oncogenic driver alteration. Our study revealed a lower prevalence of patients whose tumor harbors ALK, ROS1, and RET fusions, compared with similar data sets.

A phase I, single-center, open-label study to investigate the absorption, distribution, metabolism and excretion of encorafenib following a single oral dose of 100 mg [14 C] encorafenib in healthy male subjects

Encorafenib is a novel kinase inhibitor of BRAF V600E as well as wild-type BRAF and CRAF and has received approval, in combination with binimetinib, to treat BRAF V600E or V600K mutation-positive unresectable or metastatic melanoma or in combination with cetuximab to treat BRAF V600E mutation-positive colorectal cancer. The absorption, distribution, metabolism and excretion (ADME) of encorafenib was studied by administering [14 C] encorafenib (100 mg containing 90 μCi of radiolabeled material) to 4 healthy male subjects (NCT01436656). Following a single oral 100-mg dose of [14 C] encorafenib to healthy male subjects, the overall recovery of radioactivity in the excreta was ≥93.9% in all four subjects, indicating that good mass balance was achieved. An equal mean of 47.2% for the radioactivity dose was eliminated in the feces and urine. The percentage of the dose eliminated in the feces (5.0%) and urine (1.8%) as unchanged encorafenib was minor. Metabolism was found to be the major clearance pathway (~88% of the recovered radioactive dose) for encorafenib in humans and is predominantly mediated through N-dealkylation of the isopropyl carbamic acid methyl ester to form the primary phase 1 direct metabolite M42.5 (LHY746). Oral absorption was estimated from the radioactive dose recovered in the urine (47.2%) and the total radioactive dose recovered in the feces as metabolites (39%). Based on these values and the assumptions that encorafenib and its metabolites are stable in feces, the fraction of oral absorption was estimated to be at least ~86%.

Targeted therapies in non-small cell lung cancer: present and future

Lung cancer is the leading cause of malignancy-related death in the United States and the second most common cancer diagnosis worldwide. In the last two decades, lung cancer treatment has evolved to include advances in the development of mutation-based targeting, immunotherapy, radiation therapy, and minimally invasive surgical techniques. The discovery of lung cancer as a molecularly heterogeneous disease has driven investigation into the development of targeted therapies resulting in improved patient outcomes. Despite these advances, there remain opportunities, through further investigation of mechanisms of resistance, to develop novel therapeutics that better direct the personalization of lung cancer therapy. In this review, we highlight developments in the evolution of targeted therapies in non-small cell lung cancer, as well as future directions shaped by emerging patterns of resistance.

Therapeutic strategies for BRAF mutation in non-small cell lung cancer: a review

Lung cancer is the leading cause of cancer related deaths. Among the two broad types of lung cancer, non-small cell lung cancer accounts for 85% of the cases. The study of the genetic alteration has facilitated the development of targeted therapeutic interventions. Some of the molecular alterations which are important targets for drug therapy include Kirsten rat sarcoma (KRAS), Epidermal Growth Factor Receptor (EGFR), V-RAF murine sarcoma viral oncogene homolog B (BRAF), anaplastic lymphoma kinase gene (ALK). In the setting of extensive on-going clinical trials, it is imperative to periodically review the advancements and the newer drug therapies being available. Among all mutations, BRAF mutation is common with incidence being 8% overall and 1.5 - 4% in NSCLC. Here, we have summarized the BRAF mutation types and reviewed the various drug therapy available - for both V600 and nonV600 group; the mechanism of resistance to BRAF inhibitors and strategies to overcome it; the significance of comprehensive profiling of concurrent mutations, and the role of immune checkpoint inhibitor in BRAF mutated NSCLC. We have also included the currently ongoing clinical trials and recent advancements including combination therapy that would play a role in improving the overall survival and outcome of NSCLC.

Non-small Cell Lung Cancer With Proto-Oncogene B-Raf V600E Presenting a Distinctive Clinical Course: A Case Report

Cases of proto-oncogene B-Raf (BRAF) V600E mutation are rare, accounting for 1%-4% of non-small cell lung cancers (NSCLCs), and its clinical features remain unclear. Here, we report a case of BRAF mutation-positive lung adenocarcinoma with an atypical clinical course and long-term survival. The patient was a 63-year-old female nonsmoker who was diagnosed with stage IA adenocarcinoma after surgical resection. Five years after the surgery, cancer recurred and was treated with various cytotoxic anticancer agents. During the course of treatment, the patient was found to be BRAF V600E mutation-positive and was treated with molecular-targeted drugs. Although multiple brain, subcutaneous, and tonsillar metastases appeared, the progression was significantly slower, and the patient survived for 14 years and three months after the diagnosis. There have been few case reports of long-term survival in BRAF-positive lung cancer, and more cases need to be accumulated in the future to gather more information. Based on this case, we speculate that sensitivity to cytotoxic anticancer agents such as pemetrexed (PEM) and maintenance of performance status (PS), in addition to molecular-targeted agents, are important for long-term survival.

Molecular Epidemiology of the Main Druggable Genetic Alterations in Non-Small Cell Lung Cancer

Lung cancer is the leading cause of death for malignancy worldwide. Its molecular profiling has enriched our understanding of cancer initiation and progression and has become fundamental to provide guidance on treatment with targeted therapies. Testing the presence of driver mutations in specific genes in lung tumors has thus radically changed the clinical management and outcomes of the disease. Numerous studies performed with traditional sequencing methods have investigated the occurrence of such mutations in lung cancer, and new insights regarding their frequency and clinical significance are continuously provided with the use of last generation sequencing technologies. In this review, we discuss the molecular epidemiology of the main druggable genetic alterations in non-small cell lung cancer, namely EGFR, KRAS, BRAF, MET, and HER2 mutations or amplification, as well as ALK and ROS1 fusions. Furthermore, we investigated the predictive impact of these alterations on the outcomes of modern targeted therapies, their global prognostic significance, and their mutual interaction in cases of co-occurrence.

Pulmonary adenocarcinoma with psammoma bodies is associated with a specific endobronchial ultrasound pattern and a high prevalence of actionable driver mutations

INTRODUCTION

Pulmonary adenocarcinoma with psammoma bodies (PAPBs) is a rare histological variant whose association with a high prevalence of targetable mutations has been suggested by scant literature reports describing small series. We aim to describe the endobronchial ultrasound (EBUS) pattern and the molecular profile by next-generation sequencing of an Italian series of patients with PAPBs.

MATERIAL AND METHODS

Over a 8-year period (2012-2019), we identified 15 patients with a very uncommon endobronchial ultrasound (EBUS) heterogeneity pattern characterized by the presence of multiple to countless, punctate non-shadowing foci ("starry sky" sign) which were not evident at CT and corresponded to psammoma bodies at pathological examination. The clinical, radiological, pathological and molecular findings of these patients were retrieved and analyzed.

RESULTS

Pathological examination of the EBUS-TBNA specimens revealed malignancy (12 pulmonary adenocarcinoma, 2 breast carcinoma, 1 colonic carcinoma) and showed the presence of psammoma bodies in all of the 15 patients with the starry sky sign. Among the 12 patients with pulmonary adenocarcinoma with psammoma bodies, female sex (8/12, 66.7 %) and never-smoking habit (6/12, 50 %) were prevalent. Molecular tumor profiling using the Oncomine™ Focus DNA and RNA fusion panels was successfully performed in 11/12 patients and revealed 10 genetic alterations (BRAF mutation, 4; EGFR mutation, 2; ALK rearrangement, RET rearrangement, PIK3CA mutation, CDK4 amplification 1) in 7 patients (63.6 %).

CONCLUSION

The present series suggests that pulmonary adenocarcinoma with psammoma bodies is associated with a readily identifiable EBUS pattern and with a high prevalence of different, often uncommon and actionable, driver mutations.

Clinical Characteristics and Treatment Outcomes of 65 Patients With BRAF-Mutated Non-small Cell Lung Cancer

BRAF mutation is an oncogenic driver gene in non-small cell lung cancer (NSCLC) with low frequency. The data of patients with NSCLC harboring BRAF mutations is rare. We conducted a retrospective multicenter study in Chinese patients with NSCLC harboring BRAF mutations between Jan 2017 and Jul 2019. A total of 65 patients treated in 22 centers were included, 54 harbored BRAF-V600E mutation and 11 had non-V600E mutations, including K601E, G469S, G469V, G469A, G596R, G466R, and T599dup. Of 18 patients with early-stage disease at diagnosis and underwent a resection, the median disease-free survival (DFS) was 43.2, 18.7, and 10.1 months of stage I, II, and IIIA patients, respectively. In 46 patients with advanced-stage disease at data cutoff, disease control rate (DCR), and progression-free survival (PFS) of first-line anti-BRAF targeted therapy was superior than chemotherapy in patients harboring BRAF-V600E mutation (DCR, 100.0 vs. 70.0%, P = 0.027; median PFS, 9.8 vs. 5.4 months, P = 0.149). Of 30 V600E-mutated patients who received anti-BRAF therapy during the course of disease, median PFS of vemurafenib, dabrafenib, and dabrafenib plus trametinib was 7.8, 5.8, and 6.0 months, respectively (P = 0.970). Median PFS were similar between V600E and non-V600E patients (5.4 vs. 5.4 months, P = 0.825) to first-line chemotherapy. Nine patients were treated with checkpoint inhibitors, with median PFS of 3.0 months. Our data demonstrated the clinical benefit of anti-BRAF targeted therapy in Chinese NSCLC patients harboring BRAF-V600E mutation. The value of immunotherapy and treatment selection among non-V600E population needs further study.