The Predictive Values of Advanced Non-Small Cell Lung Cancer Patients Harboring Uncommon EGFR Mutations-The Mutation Patterns, Use of Different Generations of EGFR-TKIs, and Concurrent Genetic Alterations

From Rarity to Reality: Osimertinib's Promising Horizon in Treating Uncommon EGFR Mutations in Non-Small Cell Lung Cancer

In the realm of advanced non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) therapy with tyrosine kinase inhibitors (TKI), addressing optimal treatment for uncommon EGFR mutations like G719X in exon 18, S768I in exon 20, and L861Q in exon 21 remains a pivotal yet challenging frontier. Contrary to the well-established efficacy of EGFR-TKIs in common EGFR mutations, these uncommon alterations pose unmet medical needs due to a lack of comprehensive evidence. While afatinib, a second-generation EGFR-TKI, has received FDA approval for patients with these uncommon EGFR mutations, the approval was based on a post-hoc analysis of randomized clinical trials. Recent developments include multiple clinical trials investigating the efficacy of both second- and third-generation EGFR-TKIs in patients with uncommon EGFR mutations. A noteworthy example is a prospective phase II trial of osimertinib including the landmark UNICORN study, which has shown promising results in treating uncommon EGFR mutations. Despite various reports on the efficacy of afatinib and osimertinib in treating uncommon EGFR mutations, the appropriate use of these TKIs remains unclear. This review aims to consolidate the findings from the latest clinical trials focused on uncommon EGFR mutations, outlining variations in the therapeutic efficacy of these TKIs based on the specific genetic mutation. By synthesizing these findings, we aim to guide oncologists toward more informed decisions in employing TKIs for NSCLC with uncommon EGFR mutations other than exon 20 insertion. Additionally, we explore potential treatment strategies tailored to these patient populations to address the challenges posed by these mutations.

A case report of a lung cancer patient with two uncommon EGFR mutations and a review of the literature: two sides of the same coin

Lung cancer is the malignancy with the highest morbidity and mortality worldwide. Approximately 60% of non-small cell lung cancer (NSCLC) presents driver alterations most of which are targetable. Nowadays, limited clinical data are available regarding the efficacy of epithelial growth factor receptor (EGFR) tyrosine kinase inhibitors in patients with NSCLC harboring uncommon EGFR mutations, considering their heterogeneity. Herein, we report a rare case of EGFR-mutated lung adenocarcinoma which has developed into squamous cell carcinoma with uncommon EGFR (Ex18) compound mutations and phosphatidylinositol 3-kinase mutation receiving afatinib at the forefront.

Epidermal growth factor receptor compound and concomitant mutations: advances in precision treatment strategies

ABSTRACT

Epidermal growth factor receptor ( EGFR ) mutations are common oncogenic driver mutations in patients with non-small cell lung cancer (NSCLC). The application of EGFR-tyrosine kinase inhibitors (TKIs) is beneficial for patients with advanced and early-stage NSCLC. With the development of next-generation sequencing technology, numerous patients have been found to have more than one genetic mutation in addition to a single EGFR mutation; however, the efficacy of conventional EGFR-TKIs and the optimal treatments for such patients remain largely unknown. Thus, we review the incidence, prognosis, and current treatment regimens of EGFR compound mutations and EGFR concomitant mutations to provide treatment recommendations and guidance for patients with these mutations.

A clinical decision support system to predict the efficacy for EGFR-TKIs based on artificial neural network

BACKGROUND

The efficacy of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) was affected by numerous factors. In the study, we developed and validated an artificial neural network (ANN) system based on clinical characteristics and next-generation sequencing (NGS) to support clinical decisions.

METHODS

A multicenter retrospective non-interventional study was conducted. 240 patients from three hospitals with advanced non-small cell lung cancer (NSCLC) and EGFR mutation were tested by NGS before the first treatment. All patients received formal EGFR-TKIs treatment. Five different models were individually trained to predict the efficacy of EGFR-TKIs based on one medical center with 188 patients. Two independent cohorts from other medical centers were collected for external validation.

RESULTS

Compared with logistic regression, four machine learning methods showed better predicting abilities for EGFR-TKIs. The inclusion of NGS tests improved the predictive power of models. ANN performed best on the dataset with mutations TP53, RB1, PIK3CA, EGFR mutation sites, and tumor mutation burden (TMB). The prediction accuracy, recall and AUC were 0.82, 0.82, and 0.82, respectively in our final model. In the external validation set, ANN still showed good performance and differentiated patients with poor outcomes. Finally, a clinical decision support software based on ANN was developed and provided a visualization interface for clinicians.

CONCLUSION

This study provides an approach to assess the efficacy of NSCLC patients with first-line EGFR-TKI treatment. Software is developed to support clinical decisions.

The treatment of patients with non-small cell lung cancer carrying uncommon EGFR mutations, HER2 mutations, or brain metastases: a systematic review of pre-clinical and clinical findings for dacomitinib

Background

Accumulating evidence has shown that dacomitinib has potential activities for patients with non-small cell lung cancer (NSCLC) harboring uncommon epidermal growth factor receptor (EGFR) mutations, human epidermal growth factor receptor 2 (HER2) mutations, or central nervous system (CNS) metastases.

Methods

This study aimed to give a systematic review on its potential applications in the above settings by searching MEDLINE/PubMed, Embase, Cochrane Library, American Society of Clinical Oncology.org, European Society for Medical Oncology.org, and ClinicalTrials.gov.

Results

The literature search yielded 649 publications in total. According to our findings, dacomitinib exhibited promising efficacy in patients with major uncommon EGFR mutations (including G719X, S768I, and L861Q). Both EGFR exon 20 insertional mutation (Ex20ins) and HER2 Ex20ins demonstrated significant internal heterogeneity in response to dacomitinib, among which specific subtypes (including EGFR D770delinsGY, A763_Y764insFQEA, and HER2 M774delinsWLV) were highly sensitive. Other uncommon EGFR mutations including 18del and L747P have also been shown responsive to dacomitinib. Interestingly, limited studies suggested dacomitinib application on certain first or third generation tyrosine kinase inhibitors (TKIs)' resistant secondary mutations. Last but not least, both pre-clinical and clinical data indicated that dacomitinib has an encouraging intracranial tumor control ability, regardless of uncommon mutations.

Conclusions

Dacomitinib demonstrated good disease control on patients with NSCLC harboring major uncommon EGFR mutations and specific EGFR or HER2 mutation subtypes, and selective clinical application of dacomitinib is considerable in this setting, especially for those with intracranial metastases.

The significance of co-mutations in EGFR-mutated non-small cell lung cancer: Optimizing the efficacy of targeted therapies?

Non-small cell lung cancer (NSCLC) is the most common cause of cancer death worldwide. In non-squamous NSCLC, the identification of oncogenic drivers and the development of target-specific molecules led to remarkable progress in therapeutic strategies and overall survival over the last decade. Nevertheless, responses are limited by systematically acquired mechanisms of resistance early on after starting a targeted therapy. Moreover, mounting evidence has demonstrated that each oncogenic-driven cluster is actually heterogeneous in terms of molecular features, clinical behaviour, and sensitivity to targeted therapy. In this review, we aimed to examine the prognostic and predictive significance of oncogene-driven co-mutations, focusing mainly on EGFR and TP53. A narrative review was performed by searching MEDLINE databases for English articles published over the last decade (from January 2012 until November 2022). The bibliographies of key references were manually reviewed to select those eligible for the topic. The genetic landscape of EGFR-mutated NSCLC is more complicated than what is known so far. In particular, the occurrence of TP53 co-mutations stratify patients carrying EGFR mutations in terms of treatment response. The study provides a deeper understanding of the mechanisms underlying the variability of the genetic landscape of EGFR-mutated NSCLC and summarizes notably the clinical importance of TP53 co-mutations for an open avenue to more properly addressing the clinical decision-making in the near future.

Meta-analysis of the prognostic impact of TP53 co-mutations in EGFR-mutant advanced non-small-cell lung cancer treated with tyrosine kinase inhibitors

PURPOSE

To assess the prognostic impact of TP53 mutations in EGFR-mutant advanced NSCLC patients treated with TKIs.

METHODS

Studies exploring the clinical outcomes of EGFR mutant/TP53 wild-type versus EGFR/TP53 co-mutant patients treated with TKIs were selected. Data were cumulated by adopting a fixed and random-effect model.

RESULTS

Overall, 29 trials were eligible. The PFS analysis showed that TP53 co-mutant group has shorter PFS versus EGFR mutant/TP53 wild-type group (HR = 1.67, 95% CI 1.51-1.83, heterogeneity I² =20%, p = 0.18). Patients affected by EGFR/TP53 co-mutant NSCLC have a higher chance of shorter OS versus EGFR mutant/TP53 wild type (HR= 1.89, 95% CI 1.67-2.14, heterogeneity I² = 21%; p = 0.19). The subgroup analysis showed no significant difference between first-second versus third-generation TKIs in both PFS and OS (p = 0.31, p = 0.08).

CONCLUSIONS

TP53 mutations represent a clinically relevant mechanism of resistance to EGFR-TKIs, regardless of their generation. A personalized therapeutical approach should be explored in dedicated clinical trials.

First-line therapeutic strategy for patients with advanced non-small cell lung cancer with Leu858Arg epidermal growth factor receptor mutations: a Bayesian network meta-analysis

Aim

The objective of this network meta-analysis was to determine the most useful first-line therapeutic strategy for patients with advanced (IIIB/IV or relapsed) non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) Leu858Arg or EGFR 19del mutations.

Methods

PubMed, the Web of Science, Medline, and reports of the top three world cancer conferences (WCLC, ESMO, and ASCO) were searched for appropriated randomized controlled studies (RCTs) discussing the use of various generations of tyrosine kinase inhibitors (TKIs; gefitinib, erlotinib, icotinib, afatinib, dacomitinib, osimertinib, aumolertinib), chemotherapy [pemetrexed-based chemotherapy (PC), non-pemetrexed-based chemotherapy (NPC)], and different combined therapies (osimertinib plus bevacizumab, afatinib plus cetuximab, erlotinib plus bevacizumab, erlotinib plus ramucirumab, gefitinib plus apatinib, gefitinib plus PC, and gefitinib plus pemetrexed) to treat patients with advanced NSCLC with EGFR Leu858Arg or 19del mutations. OpenBugs and Stata software were used to analyze the data.

Results

We included 21 studies with 16 arms (including 2479 cases with EGFR Leu858Arg mutations and 3325 cases with EGFR 19del mutations). Among patients with NSCLC with EGFR Leu858Arg mutations, compared with the first-generation TKIs (such as gefitinib), the second- or third-generation TKIs [dacomitinib: hazard ratio (HR) = 0.63; 95% confidence index (CI) = (0.45, 0.89); osimertinib: HR = 0.63; 95% CI = (0.42, 0.97)] showed significant benefits in improving progression-free survival (PFS), as did afatinib plus cetuximab [HR = 1.98; 95% CI = (1.01, 3.95)], erlotinib plus bevacizumab [HR = 1.79; 95% CI = (1.22, 2.62)], and erlotinib plus ramucirumab [HR = 1.62; 95% CI = (1.07, 2.48)]. In terms of overall survival (OS), these 16 arms showed no significant differences between each other (p > 0.05). Among patients with NSCLC with EGFR 19del mutations, compared with the first- or second-generation TKIs (such as gefitinib and afatinib), aumolertinib [versus gefitinib: HR = 0.39; 95% CI = (0.28, 0.55) versus afatinib: HR = 0.53; 95% CI = (0.35, 0.84)] and osimertinib [versus gefitinib: HR = 0.40; 95% CI = (0.32, 0.51) versus afatinib: HR = 0.53, 95% CI = (0.38, 0.79)] showed significantly beneficial effects. Among these first-line therapeutic strategies for patients with EGFR Leu858Arg mutations, the combination of afatinib and cetuximab ranked as the best to prolong PFS (33.0%). For NSCLC patients with 19del mutations, however, osimertinib plus bevacizumab was the best at prolonging PFS (84.3%).

Conclusion

For NSCLC patients with EGFR Leu858Arg mutations, the second-generation TKIs, the third-generation TKIs, and the combined treatments showed better efficacy than the first-generation TKIs for PFS. There were, however, no significant differences between each group for OS.

Dacomitinib for Advanced Non-small Cell Lung Cancer Patients Harboring Major Uncommon EGFR Alterations: A Dual-Center, Single-Arm, Ambispective Cohort Study in China

Objective: Dacomitinib has been approved for non-small-cell lung cancer (NSCLC) patients harboring classical epidermal growth factor receptor (EGFR) mutations; however, clinical evidence of its activity on major uncommon EGFR mutations is currently limited.

Materials and methods: This was a dual-center, single-arm, ambispective cohort study in China. Patients with histologically confirmed metastatic or recurrent NSCLC harboring major uncommon EGFR mutations were eligible for the study. The objective response rate and disease control rate were determined by RECIST 1.1 every 1–2 months. Adverse events were assessed by CTCAE 5.0.

Results: In total, 32 NSCLC patients were enrolled between July 2020 and January 2022, and 18 (56.3%) patients received dacomitinib as first-line therapy. Median age was 64 years, and 20 (62.5%) were female. The mutations identified were G719X (n = 24; 75%), followed by L861X (n = 10; 31.3%), and S768I (n = 8; 25%). In the first-line setting, 72.2% of patients (13/18) had a confirmed partial response and 100% (18/18) had disease control, and the median progression-free survival (PFS) and overall survival (OS) were unreached. In the whole cohort, 56.3% of patients (18/32) had a confirmed partial response and 90.6% (29/32) had disease control, and the median PFS was 10.3 months (95% confidence interval, 6.1–14.5) and the median OS was 36.5 months. Except for one case not available for brain re-evaluation, control of the intracranial metastases was observed in 13 patients (13/14, 92.9%). No grade 4–5 adverse events (AEs) occurred, but all patients had grade 1–2 AEs, and 12.5% (4/32) patients required a dosage reduction due to intolerable AEs.

Conclusions: Dacomitinib demonstrated favorable activity with manageable toxicity in patients with NSCLC harboring major uncommon EGFR mutations.

Afatinib 30 mg in the treatment of common and uncommon EGFR-mutated advanced lung adenocarcinomas: a retrospective, single-center, longitudinal study

Background

Afatinib 30 mg has been proved to be with comparable efficacy but more tolerable than the dose of 40 mg for Asian patients with non-small cell lung cancer (NSCLC). This study aimed to investigate the clinical outcomes of afatinib at 30 mg/d in the treatment of advanced lung adenocarcinomas (LAD) with common and uncommon epidermal growth factor receptor (EGFR) mutations.

Methods

EGFR-mutated advanced LAD patients receiving afatinib (30 mg/d) from January 2017 to November 2021 were retrospectively included. EGFR status was classified into three subtypes, namely common mutations including exon 19 deletions (19del) and exon 21 L858R (21L858R), uncommon mutations including G719X, L861Q, S768I, and complex mutations, and separately exon 20 insertions (20ins). Progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR) and adverse events (AEs) were analyzed during regular follow-up.

Results

The overall median PFS of totally 58 included patients was 9.83 [95% confidence index (CI): 5.76–13.91] months. The number of patients with common, uncommon, and 20ins mutations was 32 (55.2%), 19 (32.8%) and 7 (12.1%), respectively. Baseline characteristics did not differ significantly among the three subtypes. The corresponding median PFS was 13.97 (12.06–15.89), 8.48 (0.32–16.64), and 3.78 (1.93–5.64) months, respectively (P=0.002). In the first-line setting, patients with common and uncommon mutations had a significantly longer PFS compared to those with 20ins [14.53 (13.53–15.53) vs. 10.39 (4.87–15.91) vs. 2.37 (0.00–5.11) months, P<0.001]. The first-line ORR showed significant differences among the three subtypes (60% vs. 80% vs. 0.0%, P=0.023). All-grade AEs occurred in 22 patients (37.9%). AEs ≥ grade 3 mainly included diarrhea (8.6%), and none of the patients discontinued treatment due to severe AEs.

Conclusions

Afatinib at 30 mg/d is associated with a favorable efficacy and tolerability in the treatment of advanced LAD with common and major uncommon EGFR mutations except 20ins. Further large-scale prospective studies are warranted to confirm our findings.

Uncommon EGFR Compound Mutations in Non-Small Cell Lung Cancer (NSCLC): A Systematic Review of Available Evidence

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.