High-dose, weekly erlotinib is not an effective treatment in EGFR-mutated non-small cell lung cancer-patients with acquired extracranial progressive disease on standard dose erlotinib

Activity of EGFR Tyrosine Kinase Inhibitors in NSCLC With Refractory Leptomeningeal Metastases

INTRODUCTION

Leptomeningeal metastases (LMs) are associated with dismal prognosis in NSCLC. Optimal management remains unknown in patients with EGFR-mutated NSCLC after initial tyrosine kinase inhibitor (TKI) failure.

METHODS

We conducted a multicenter retrospective study including patients with EGFR-mutated NSCLC and LM. TKI failure was defined as diagnosis of LM on TKI, or progression of known LM on TKI.

RESULTS

Ninety-two patients were included, median age of 60 years, predominantly female (68%), never-smokers (74%). EGFR mutations included L858R (45%), exon 19 deletions (28%), or other mutations (14%). Median time to LM diagnosis was 18.5 months after initial diagnosis of advanced NSCLC. LM was diagnosed after a median of 2 (range: 0-9) systemic therapies. Median overall survival from LM diagnosis was 6.1 months (95% confidence interval [CI]: 4.2-7.6 months). Among 87 patients with TKI failure, patients rechallenged with TKI (n = 50) had a median LM overall survival of 7.6 months (95% CI: 5.7-10.9) compared to 4.2 months (95% CI: 1.6-6.7) in patients without further therapy. Overall, 60% of patients rechallenged with TKI experienced clinical benefit (clinical response or stable disease >2 months), and 23% were treatment failure-free at 6 months. Clinical benefit was reported in 11 of 20 (55%) patients treated with erlotinib after afatinib or gefitinib. Strategies based on increasing dose intensity (n = 17) yielded clinical benefit in 59% of patients. All four patients who received osimertinib after first- and second-generation TKI experienced clinical benefit.

CONCLUSIONS

TKI rechallenge strategies, including dosing intensification, may improve clinical outcomes of patients with LM from EGFR-mutated NSCLC after initial TKI failure.

Brain Metastases in Oncogene-Addicted Non-Small Cell Lung Cancer Patients: Incidence and Treatment

Brain metastases (BM) are common in non-small cell lung cancer patients including in molecularly selected populations, such as EGFR-mutant and ALK-rearranged tumors. They are associated with a reduced quality of life, and are commonly the first site of progression for patients receiving tyrosine kinase inhibitors (TKIs). In this review, we summarize incidence of BM and intracranial efficacy with TKI agents according to oncogene driver mutations, focusing on important clinical issues, notably optimal first-line treatment in oncogene-addicted lung tumors with upfront BM (local therapies followed by TKI vs. TKI monotherapy). We also discuss the potential role of newly emerging late-generation TKIs as new standard treatment in oncogene-addicted lung cancer tumors compared with sequential strategies.

Targeted drugs for systemic therapy of lung cancer with brain metastases

Brain metastases are very common in lung cancer patients. The condition of these patients is complicated and difficult to treat, and adverse reactions following treatment can affect the nervous system, which severely reduces quality of life. Lung cancers are categorized as small cell lung cancers and non-small cell lung cancers. Patients with brain metastasis of small cell lung cancers are generally treated with brain radiotherapy and systemic chemotherapy, but stage III/IV patients with brain metastasis of non-small cell lung cancers are generally not responsive to radiotherapy or chemotherapy. With the recent development of targeted drugs, tumor molecular profile detection allows the selection of appropriate targeted drugs for adjuvant pharmacological treatment of brain metastasis in lung cancer patients. In recent years, immune checkpoint inhibitors have emerged and have been approved by the Food and Drug Administration (FDA) for the treatment of certain cancers, but their efficacy in lung cancer patients with brain metastases still needs to be confirmed. This paper focuses on highlighting drugs for targeted therapy of brain metastasis in lung cancer patients and their molecular targets and mechanisms of drug resistance.

Systemic Treatment of Brain Metastases

Lung cancer continues to be the leading cause of cancer-related mortality in the United States. Brain metastases are a significant problem in patients with lung cancer and have conventionally been treated with whole-brain radiation. This article reviews the data for systemic chemotherapy to treat brain metastasis from lung cancer and examines the activity of small molecule tyrosine kinase inhibitors for the targeted therapy for brain metastases from EGFR-mutant and ALK-rearranged non-small cell lung cancer. Future directions for evaluating the role of immunotherapy in treating brain metastasis are also discussed.