Afatinib successfully treated leptomeningeal metastasis during erlotinib treatment in a patient with EGFR-mutant (Exon18:G719S) lung adenocarcinoma as a second-line chemotherapy

Effective Treatment With Afatinib of Lung Adenocarcinoma With Leptomeningeal Metastasis Harboring the Exon 18 p.G719A Mutation in the EGFR Gene Was Detected in Cerebrospinal Fluid: A Case Report

Background: In patients with lung adenocarcinoma and leptomeningeal metastases, it remains unknown whether non-classical mutations in the epidermal growth factor receptor (EGFR) gene can be detected in the cerebrospinal fluid (CSF) and how it may be used to design directed therapy.

Methods: On April 18, 2018, the Interventional Department of Tianjin Huanhu Hospital admitted a 34-years-old male patient with lung adenocarcinoma and leptomeningeal metastasis. An emergency lateral ventriculoperitoneal shunt was performed to relieve the clinical symptoms of intracranial hypertension. Next-generation sequencing (NGS) of the CFS specimens revealed a mutation in EGFR exon 18 p.G719A, and afatinib was administered. Follow-up showed significantly relieved headache, with significantly reduced soft leptomeningeal abnormal enhancement as revealed by enhanced magnetic resonance imaging and significantly smaller tumors in the left lung by chest computed tomography. Carcinoembryonic antigens (CEAs) in cerebrospinal fluid and peripheral blood were significantly reduced. The patient responded well to afatinib, with mild adverse complications. The patient died on October 27, 2019 from respiratory failure as a result of lung infection unrelated to cancer progression. The overall survival (OS) using afatinib was 530 days.

Conclusion: CSF can be used as a liquid biopsy for NGS gene detection in patients with lung adenocarcinoma and leptomeningeal metastases. Afatinib exhibits a beneficial effect in patients with lung adenocarcinoma and leptomeningeal metastases harboring the EGFR exon 18 p.G719A mutation.

Long-term Survival With Afatinib in a Patient With Lung Adenocarcinoma Harboring Double Uncommon EGFR L861Q and G719X Mutations

BACKGROUND

In the majority of non-small cell lung cancer (NSCLC) patients with uncommon EGFR mutations, first generation epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are ineffective. The second-generation TKI, afatinib, is considered effective in patients with uncommon mutations, however, long-term survivors have been rare.

CASE REPORT

We report herein a patient with lung adenocarcinoma harboring double uncommon EGFR L861Q and G719X mutations, who is free of disease 32 months after initiation of afatinib therapy. To our best knowledge, this patient has the longest response among other patients with double uncommon mutations.

CONCLUSION

Patients with this type of NSCLC may obtain long-term survival with afatinib.

Next-generation Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors for Leptomeningeal Carcinomatosis: Review of 2 Cases

INTRODUCTION

Epidermal growth factor receptor (EGFR) mutation status is strongly correlated with leptomeningeal carcinomatosis in non-small cell lung cancer. Historically, patients were treated with radiotherapy, intrathecal chemotherapy or first-generation EGFR tyrosine kinase inhibitors (TKIs); however, most would eventually develop resistance and disease progression. Therefore, recent interest has sparked in investigating next-generation EGFR-TKI monotherapy.

CASE REPORTS

We describe 2 patients with non-small cell lung adenocarcinoma who later presented with leptomeningeal disease, treated with next-generation EGFR-TKI monotherapy, independent of whole-brain radiotherapy, with favorable response and outcome.

CONCLUSIONS

The next-generation EGFR-TKIs may have improved success in treatment of leptomeningeal metastases in non-small cell lung adenocarcinoma when compared with the first-generation and second-generation EGFR-TKIs. Next-generation EGFR-TKI monotherapy should be considered in select patients with leptomeningeal metastases from lung adenocarcinoma. More research is needed to review this potential therapeutic option, especially for use as first-line therapy.

Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors for Central Nervous System Metastases from Non-Small Cell Lung Cancer

Central nervous system (CNS) metastases are a common complication in patients with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC), resulting in a poor prognosis and limited treatment options. Treatment of CNS metastases requires a multidisciplinary approach, and the optimal treatment options and sequence of therapies are yet to be established. Many systemic therapies have poor efficacy in the CNS due to the challenges of crossing the blood-brain barrier (BBB), creating a major unmet need for the development of agents with good BBB-penetrating biopharmaceutical properties. Although the CNS penetration of first- and second-generation EGFR tyrosine kinase inhibitors (TKIs) is generally low, EGFR-TKI treatment has been shown to delay time to CNS progression in patients with CNS metastases from EGFR-mutated disease. However, a major challenge with EGFR-TKI treatment for patients with NSCLC is the development of acquired resistance, which occurs in most patients treated with a first-line EGFR-TKI. Novel EGFR-TKIs, such as osimertinib, have been specifically designed to address the challenges of acquired resistance and poor BBB permeability and have demonstrated efficacy in the CNS. A rational, iterative drug development process to design agents that could penetrate the BBB could prevent morbidity and mortality associated with CNS disease progression. To ensure a consistent approach to evaluating CNS efficacy, special consideration also needs to be given to clinical trial endpoints.

IMPLICATIONS FOR PRACTICE

Historically, treatment options for patients who develop central nervous system (CNS) metastases have been limited and associated with poor outcomes. The development of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) has improved outcomes for patients with EGFR-mutated disease, and emerging data have demonstrated the ability of these drugs to cross the blood-brain barrier and elicit significant intracranial responses. Recent studies have indicated a role for next-generation EGFR-TKIs, such as osimertinib, in the treatment of CNS metastases. In the context of an evolving treatment paradigm, treatment should be individualized to the patient and requires a multidisciplinary approach.

Leptomeningeal metastasis from systemic cancer: Review and update on management

Leptomeningeal metastasis is an uncommon and typically late complication of cancer with a poor prognosis and limited treatment options. Diagnosis is often challenging, with nonspecific presenting symptoms ranging from headache and confusion to focal neurologic deficits, such as cranial nerve palsies. Standard diagnostic evaluation involves a neurologic examination, magnetic resonance imaging of the brain and spine with gadolinium, and cytologic evaluation of the cerebral spinal fluid. Therapy entails a multimodal approach focused on palliation with surgery, radiation, and/or chemotherapy, which may be administered systemically or directly into the cerebral spinal fluid. Limited trial data exist to guide treatment, and current regimens are based primarily on expert opinion. Although newer targeted and immunotherapeutic agents are under investigation and have shown promise, an improved understanding of the biology of leptomeningeal metastasis and treatment resistance as well as additional randomized controlled studies are needed to guide the optimal treatment of this devastating disease. Cancer 2018;124:21-35. © 2017 American Cancer Society.