Real-World Treatment Patterns and Outcomes of First-Line Immunotherapy Among Patients With Advanced Nonsquamous NSCLC Harboring BRAF, MET, or HER2 Alterations

Novel molecular subtypes of METex14 non-small cell lung cancer with distinct biological and clinical significance

Not all MET exon 14 skipping (METex14) NSCLC patients benefited from MET inhibitors. We hypothesized an inter-tumoral heterogeneity in METex14 NSCLC. Investigations at genomic and transcriptomic level were conducted in METex14 NSCLC samples from stage I-III and recurrent/metastatic patients as discovery and validation cohort. Four molecular subtypes were discovered. MET-Driven subtype, with the worst prognosis, displayed MET overexpression, enrichment of MET-related pathways, and higher infiltration of fibroblast and regulatory T cells. Immune-Activated subtype having the most idea long-term survival, had higher tertiary lymphoid structures, spatial co-option of PD-L1+ cancer cells, and GZMK+ CD8+ T cell. FGFR- and Bypass-Activated subtypes displayed FGFR2 overexpression and enrichments of multiple oncogenic pathways respectively. In the validation cohort, patients with MET-Driven subtype had better response to MET inhibitors than those with MET overexpression. Thus, molecular subtypes of METex14 NSCLC with distinct biological and clinical significance may indicate more precise therapeutic strategies for METex14 NSCLC patients.

Pathways and targeting avenues of BRAF in non-small cell lung cancer

INTRODUCTION

BRAF is a serine-threonine kinase implicated in the regulation of MAPK signaling cascade. BRAF mutation-driven activation occurs in approximately 2-4% of treatment-naive non-small cell carcinomas (NSCLCs). BRAF upregulation is also often observed in tumors with acquired resistance to receptor tyrosine kinase inhibitors (TKIs).

AREAS COVERED

This review describes the spectrum of BRAF mutations and their functional roles, discusses treatment options available for BRAF p.V600 and non-V600 mutated NSCLCs, and identifies some gaps in the current knowledge.

EXPERT OPINION

Administration of combined BRAF/MEK inhibitors usually produces significant, although often a short-term, benefit to NSCLC patients with BRAF V600 (class 1) mutations. There are no established treatments for BRAF class 2 (L597, K601, G464, G469A/V/R/S, fusions, etc.) and class 3 (D594, G596, G466, etc.) mutants, which account for up to two-thirds of BRAF-driven NSCLCs. Many important issues related to the use of immune therapy for the management of BRAF-mutated NSCLC deserve further investigation. The rare occurrence of BRAF mutations in NSCLC is compensated by high overall incidence of lung cancer disease; therefore, clinical studies on BRAF-associated NSCLC are feasible.

TP53 co-mutations in advanced lung adenocarcinoma: comparative bioinformatic analyses suggest ambivalent character on overall survival alongside KRAS, STK11 and KEAP1 mutations

Background

Recently, we could show that the co-mutations of KRAS + KEAP1, STK11 + KEAP1 and KRAS + STK11 + KEAP1 lead to a significantly shorter median overall survival (mOS) across treatments by analyzing multiple datasets. TP53, a tumor suppressor gene, plays a crucial role in regulating cell cycle progression. Its mutations occur in approximately 40-50% of non-small lung cancer (NSCLC). Co-occurrence of all four mentioned mutations has been a matter of debate for years. The aim of this study was to assess the distribution of these four mutations and the influence of the different co-mutational patterns on survival.

Methods

We present a comparative bioinformatic analysis and refer to data of 4,109 patients with lung adenocarcinoma (LUAD).

Results

Most of the mutations within the LUAD belong to TP53-only (29.0%), quadruple-negative (25.9%) and KRAS-only (13.4%). Whereas TP53-mutations seem to have protective effects in the context of further KEAP1- and KRAS + KEAP1-alterations (improved mOS), their role seems contrary if acquired in an already existing combination of mutations as KRAS + STK11, KRAS + STK11 + KEAP1 and STK1 + KEAP1. TP53 co-mutationshad a negative influence on KRAS-only mutated LUAD (mOS reduced significantly by more than 30%).

Discussion

These data underline the need for complex mutational testing to estimate prognosis more accurately in patients with advanced LUAD.

Efficacy of chemo-immunotherapy in metastatic BRAF-mutated lung cancer: a single-center retrospective data

Background

The effectiveness of combining immune checkpoint inhibitors (ICIs) with chemotherapy in treating non-small cell lung cancers (NSCLCs) with BRAF mutations has not been sufficiently explored.

Methods

We compiled data from 306 NSCLC patients with identified BRAF mutations. We looked at efficacy by assessing the objective response rate (ORR) and disease control rate (DCR), as well as survival through measuring progression-free survival (PFS) and overall survival (OS).

Results

Out of the patient pool, 44 were treated with a regimen of immune-chemotherapy. Patients undergoing ICI in combination with chemotherapy had a median PFS of 4 months, and the median OS was recorded at 29 months. There was a notable increase in OS in patients receiving first-line treatment versus subsequent lines (29 vs 9.75 months, p=0.01); however, this was not the case with PFS (9 vs 4 months, p=0.46). The ORR for patients on ICIs was 36.3%. PFS and OS rates did not significantly differ between patients with the BRAF-V600E mutation and those with non-V600E mutations (p=0.75 and p=0.97, respectively). Additionally, we found a significant variation in PD-L1 expression between those who responded to treatment and those who didn't (p=0.04).

Conclusion

Our findings indicate that chemo-immunotherapy as an initial treatment may lead to improved OS in patients with BRAF-mutated NSCLC when compared to its use in subsequent lines of therapy. Further studies are needed to validate these results and to delve deeper into how specific types of BRAF mutations and PD-L1 expression levels might predict a patient's response to treatments in NSCLC.