Retrospective analysis of independent predictors of progression‐free survival in patients with EGFR mutation‐positive advanced non‐small cell lung cancer receiving first‐line osimertinib

Epidermal growth factor receptor-mutated lung carcinomas with insufficient response to epidermal growth factor receptor inhibitors

Administration of single-agent epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) is a standard treatment option for metastatic non-small cell lung carcinomas with EGFR exon 19 deletions (ex19del) and L858R substitutions. However, there is a significant interpatient heterogeneity with regard to the degree of the response and its duration. Patients with EGFR ex19del mutation, TP53 wild-type, good performance status, low tumor burden and no circulating tumor DNA (ctDNA) at baseline have the best chances to derive pronounced benefit from TKI therapy. In contrast, subjects with EGFR L858R substitution, mutated TP53, poor overall condition, high tumor volume and detectable ctDNA are generally poor responders to EGFR inhibitors. ctDNA dynamics in the first days or weeks of treatment allows reliable identification of patients, who are very unlikely to derive clinically meaningful benefit from single-agent TKIs. These patients are candidates for clinical trials, which may involve the addition of chemotherapy and antiangiogenic drugs to patients, who failed to achieve immediate benefit from TKI monotherapy.

Baseline genetic abnormalities and effectiveness of osimertinib treatment in patients with chemotherapy-naïve EGFR-mutated NSCLC based on performance status

BACKGROUND/AIM

For patients treated with osimertinib as first-line therapy, there have been no studies comparing both progression-free survival (PFS) and overall survival (OS) according to performance status (PS). Furthermore, no studies have examined differences in baseline genetic abnormalities between patients with poor and good PS. Therefore, we aimed to investigate differences in baseline genetic abnormalities and treatment effects between patients with poor and good PS who received osimertinib as the primary treatment.

PATIENTS AND METHODS

This is a secondary analysis of the ELUCIDATOR study, which is a multi-center prospective observational study in Japan that assessed mechanisms underlying resistance to osimertinib as first-line treatment for advanced non-small cell lung cancer with epidermal growth factor receptor mutations.

RESULTS

There were 153 and 25 patients in the good and poor PS groups, respectively. Multivariate analysis revealed no significant between-group differences in PFS (hazards ratio [HR]: 0.98, 95% confidence interval [CI]: 0.52-1.72, p = 0.946). Multivariate analysis of OS revealed that poor PS was a poor prognostic factor (HR: 2.67, 95% CI: 1.43-4.73, p = 0.003). Regarding baseline genetic abnormalities, there was a significant increase in APC-positive cases (20.0% vs. 2.2%, p = 0.009) and a trend toward more CTNNB1-positive cases in the poor PS group than in the good PS group (14.3% vs. 2.9%, p = 0.062).

CONCLUSION

There was no between-group difference in PFS, although OS was significantly inferior in the poor PS group. Additionally, there was a significant increase in APC-positive cases and a trend toward more CTNNB1-positive cases in the poor PS group.

Distinct Progression and Efficacy of First-Line Osimertinib Treatment According to Mutation Subtypes in Metastatic NSCLC Harboring EGFR Mutations

Introduction

Osimertinib (OSI), a third-generation EGFR tyrosine kinase inhibitor, is the standard treatment for patients with naive EGFR-mutant NSCLC. Nevertheless, information on how the mutation subtype affects disease progression after the failure of OSI treatment is scarce.

Methods

We retrospectively reviewed patients with EGFR-mutant NSCLC who received OSI as a first-line treatment between April 2015 and December 2021.

Results

This study included 229 patients. The objective response rate was 71%, with intracranial and extracranial response rates of 71% and 90%, respectively. The median progression-free survival was 23.3 mo (95% confidence interval [CI]: 19.6-26.7), and the median overall survival was 33.7 mo (95% CI: 31.3-58.6). Multivariate analysis revealed that the EGFR exon 21 L858R point mutation (L858R) (hazard ratio [HR] = 1.56, 95% CI: 1.04-2.34, p = 0.0328) and liver metastasis (HR = 2.63, 95% CI: 1.53-4.49, p = 0.0004) were significant predictors of progression-free survival in OSI treatment. The concomitant disease progression involving the central nervous system metastasis was significantly more common in patients with L858R (p = 0.048), whereas concomitant disease progression involving primary lesions was significantly more common in patients with exon 19 deletion mutation (p = 0.01). In addition, the probability of disease progression over time was higher for L858R compared with that for exon 19 deletion mutation, in patients with central nervous system metastasis (log-rank test, p = 0.027).

Conclusions

The mutation subtype had an impact not only on the clinical outcome of the first-line OSI treatment but also on progression patterns after OSI treatment in patients with NSCLC harboring EGFR mutations.

Tailoring Therapeutic Strategies in Non-Small-Cell Lung Cancer: The Role of Genetic Mutations and Programmed Death Ligand-1 Expression in Survival Outcomes

BACKGROUND

This study aims to assess the real-world impact of advancements in first-line systemic therapies for non-small-cell lung cancer (NSCLC), focusing on the role of driver gene mutations and programmed death-ligand 1 (PD-L1) expression levels.

METHODS

Conducted across eight medical facilities in Japan, this multicenter, retrospective observational research included 863 patients diagnosed with NSCLC and treated between January 2015 and December 2022. The patients were categorized based on the type of systemic therapy received: cytotoxic agents, molecular targeting agents, immune checkpoint inhibitors, and combination therapies. Comprehensive molecular and immunohistochemical analyses were conducted, and statistical evaluations were performed.

RESULTS

The median overall survival (OS) shows significant variations among treatment groups, with targeted therapies demonstrating the longest OS. This study also revealed that high PD-L1 expression was common in the group treated with immune checkpoint inhibitors. Multivariate analysis was used to identify the type of anticancer drug and the expression of PD-L1 at diagnosis as the impactful variables affecting 5-year OS.

CONCLUSIONS

This study underscores the efficacy of targeted therapies and the critical role of comprehensive molecular diagnostics and PD-L1 expression in affecting OS in NSCLC patients, advocating for their integration into routine clinical practice.

Osimertinib as first-line treatment for recurrent lung cancer patients with EGFR mutation

Background

Although osimertinib was approved as adjuvant therapy for lung cancer patients with EGFR mutation in various countries, there is still some ongoing debate as osimertinib has been approved based on disease-free survival (DFS) rather than overall survival (OS). We curated a case series in which we documented patterns of recurrence and efficacy and safety of osimertinib after recurrence.

Methods

Patients who received osimertinib as first-line treatment for postoperative recurrence between September 2018 and January 2023 were included. Clinicopathological factors, duration of osimertinib treatment (DoT), and adverse events were collected and analyzed.

Results

Twenty patients received osimertinib [male, n=6; median age, 75 years (range, 55-85 years)]. The EGFR mutation type was L858R in 11 patients and exon 19 deletion in eight patients. The performance status (PS) was 0 or 1 in all but two patients, who had symptomatic brain metastasis and were therefore PS 3. The first site of postoperative recurrence was locoregional in five patients and distant in 15 patients, including seven with brain metastasis. As of February 2023, 10 patients were still on osimertinib, including three with brain metastasis. Patients with brain metastasis or poor PS had a considerably shorter DoT than their counterparts. Three patients with symptomatic brain metastasis or leptomeningeal metastasis initially responded to osimertinib, but all died of disease progression. Five patients discontinued osimertinib due to serious adverse effects (pneumonitis, drug eruption, and heart failure).

Conclusions

Although osimertinib exerts great disease control, even in patients with brain metastasis or poor PS, their presence was associated with a poor prognosis, even with osimertinib treatment. Therefore, adjuvant osimertinib is recommended unless contraindicated.

Association of PD-L1 tumor proportion score ≥20% with early resistance to osimertinib in patients with EGFR-mutated NSCLC

BACKGROUND

The relationship between epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) resistance, including osimertinib, and programmed cell death-ligand 1 (PD-L1) expression status in EGFR-mutated non-small cell lung carcinoma (NSCLC) remains unclear.

PATIENTS AND METHODS

We retrospectively analyzed 64 patients with unresectable advanced or metastatic NSCLC carrying EGFR exon 19 deletions (ex19del) or EGFR exon 21 L858R substitutions (L858R) who received osimertinib as the first-line treatment. We compared progression-free survival (PFS) between eligible patients with PD-L1 tumor proportion scores (TPS) ≥20% and PD-L1 TPS <20% using the Kaplan-Meier survival plots with a log-rank test. Multivariate analysis was performed to examine the poor prognostic factors of PFS.

RESULTS

The PD-L1 TPS ≥20% group included 22 cases (median [range] age: 70.5 [33-86] years; 10 women [45.5%]; 11 current or ex-smokers [50%]); ECOG performance status (PS) of 0-1/2/3/4 was noted in 16/4/1/1 patients, respectively. The PD-L1 TPS <20% group included 42 patients (median [range] age 73 [43-88] years; 29 women [69%]; 12 current or ex-smokers [28.6%]); ECOG PS of 0-1/2/3/4 was noted in 33/6/3/0 cases, respectively. The median PFS was 9.1 and 28.1 months in the PD-L1 TPS ≥20% and PD-L1 TPS <20% groups, respectively (log-rank p = 0.013). Multivariate analysis revealed that PD-L1 TPS ≥20% was associated with PFS (hazard ratio: 2.35, 95% confidence interval: 1.09-5.08, p = 0.030).

CONCLUSION

PD-L1 TPS ≥20% in patients with EGFR-mutated NSCLC may be associated with early resistance to osimertinib.