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

Therapeutic role of EGFR - Tyrosine kinase inhibitors in non-small cell lung cancer with leptomeningeal metastasis

Leptomeningeal metastasis (LM) is a significant complication that advances fast and has a poor prognosis for patients with advanced non-small cell lung cancer (NSCLC) who have epidermal growth factor receptor (EGFR) mutations. Current therapies for LM are inconsistent and ineffective, and established techniques such as radiation, chemotherapy, and surgery continue to fall short of potential outcomes. Nonetheless, EGFR tyrosine kinase inhibitors (TKIs) exhibit potent anti-tumor activity and hold considerable promise for NSCLC patients with EGFR mutations. Thus, assessing EGFR-TKIs effectiveness in treating these central nervous system (CNS) problems is crucial. This review integrates current literature on the intracranial efficacy of EGFR-TKIs to explore the varying impacts of approved EGFR-TKIs in LM patients and the therapeutic possibilities presented by other EGFR-TKIs in development. To delineate the optimal clinical treatment strategy, further exploration is needed regarding the optimal sequencing of EGFR-TKIs and the selection of alternative therapy options following initial treatment failure with EGFR-TKIs.

Leptomeningeal metastases in non-small cell lung cancer: Diagnosis and treatment

Leptomeningeal metastasis (LM) is a rare complication of non-small cell lung cancer (NSCLC) with highly mortality. LM will occur once tumor cells spread to the cerebrospinal fluid (CSF) space. Patients may suffer blindness, paralysis, and mental disorders that seriously affect their quality of life. There is a clear unmet need to improve the efficacy of diagnosis and treatment of LM. To better solve this problem, it is helpful to clarify the potential mechanisms of LM. Clinical manifestations, magnetic resonance imaging, and CSF biopsy are the key components in the diagnosis of NSCLC with LM. CSF cytology is insufficient and should be combined with liquid biology. The application of radiotherapy, intrathecal treatment, targeted therapy and immunotherapy provides more options for LM patients. Each treatment has a particular level of efficacy and can be used alone or in combination for individual patients. New technologies in radiotherapy, drug repositioning in intrathecal treatment, and the higher CSF permeability in TKIs have brought new breakthroughs in the treatment of LM. This review focused on clarifying the potential mechanisms, discussing the major clinical challenges, and summarizing recent advances in the diagnosis and treatment of LM from NSCLC. Future research is essential to improve the efficiency of diagnosis, to optimize therapy and to enhance patient prognosis.

Subsequent treatments beyond progression on osimertinib in EGFR-mutated NSCLC and leptomeningeal metastases

BACKGROUND

Despite the reported efficacy of osimertinib, central nervous system (CNS) progression is still frequent in EGFR-mutated NSCLC. This study aimed to reveal site-specific resistant mechanisms to osimertinib and investigate subsequent treatments for leptomeningeal metastases (LM).

METHODS

EGFR-mutated NSCLC with LM who progressed on osimertinib were included. Molecular analysis of cerebrospinal fluid (CSF) at osimertinib progression was performed. Subsequent treatments of LM were collected and analyzed.

RESULTS

A total of 246 patients were identified. Only those with LM as a progression site on osimertinib were included (n=81). In 58 CSF-plasma pairs, more alterations were uniquely detected in CSF (77%) than in plasma (7%). These mechanisms led to 22 patients receiving matched targeted therapy. Among them, 16 (72.7%) had a clinical response. The median overall survival was 7.2 months. For non-matched therapy (n=59), the osimertinib combination had a longer median overall survival than the regimen switch in CNS-only progression (15.3 vs. 7 months, p=0.03). Finally, serial monitoring by CSF revealed the potential evolution of LM.

CONCLUSIONS

Private resistant mechanisms in CSF might match osimertinib-resistant LM for targeted therapy. Besides, continuing osimertinib with intensification strategy might prolong survival, especially for those with CNS-only progression. Prospective  exploration is needed.

Cerebrospinal Fluid Cell-Free DNA-Based Detection of High Level of Genomic Instability Is Associated With Poor Prognosis in NSCLC Patients With Leptomeningeal Metastases

Introduction

Leptomeningeal metastasis (LM) commonly occurs in non-small cell lung cancer (NSCLC) patients and has a poor prognosis. Due to limited access to leptomeningeal lesions, the genetic characteristics of LM have not been explored to date. Cerebrospinal fluid (CSF) may be the most representative liquid biopsy medium to obtain genomic information from LM in NSCLC.

Methods

CSF biopsies and matched peripheral blood biopsies were collected from 33 NSCLC patients with LM. We profiled genetic alterations from LM by comparing CSF cell-free DNA (cfDNA) with plasma cfDNA. Somatic mutations were examined using targeted sequencing. Genomic instability was analyzed by low-coverage whole-genome sequencing (WGS).

Results

Driver mutations were detected in 100% of CSF cfDNA with much higher variant allele frequency than that in matched plasma cfDNA (57.5%). Furthermore, we found that the proportions of CSF cfDNA fragments below 150 bp were significantly higher than those in plasma cfDNA. These findings indicate enrichment of circulating tumor DNA (ctDNA) in CSF and explain the high sensitivity of mutation detection in the CSF. The absence of some mutations in CSF cfDNA-especially the first-/second-generation mutation T790M, which confers resistance to epidermal growth factor receptor (EGFR)-Tyrosine kinase inhibitors (TKIs)-that were present in plasma cfDNA samples indicates different mechanisms of cancer evolution between LM and extracranial lesions. In addition, 86.6% of CSF ctDNA samples revealed high levels of genomic instability compared with 2.5% in plasma cfDNA samples. A higher number of large-scale state transitions (LSTs) in CSF cfDNA were associated with a shorter overall survival (OS).

Conclusion

Our results suggest that LM and extracranial lesions develop independently. Both CSF cfDNA genetic profiling and plasma cfDNA genetic profiling are necessary for clinical decision-making for NSCLC patients with LM. Through CSF-based low-coverage WGS, a high level of LSTs was identified as a potential biomarker of poor prognosis.

Standard-Dose Osimertinib in EGFR-Mutated Non-Small-Cell Lung Adenocarcinoma With Leptomeningeal Disease

PURPOSE

Leptomeningeal disease (LMD) in epidermal growth factor receptor (EGFR)-mutant lung adenocarcinoma is associated with a poor prognosis and limited treatment options. Osimertinib is a potent third-generation EGFR tyrosine kinase inhibitor with confirmed CNS penetration. This study reports on outcomes of patients with EGFR-mutated non-small-cell lung cancer who developed LMD and were subsequently treated with osimertinib.

METHODS

We identified patients treated with osimertinib 80 mg PO daily under a compassionate access scheme across nine tertiary Australian institutes between July 2017 and July 2020. Patient demographics, tumor characteristics, and treatment history were collected. Median overall survival, median progression-free survival, disease control rates (DCR), and overall response rates (ORR) were assessed. Kaplan-Meier analysis was performed and descriptive statistics were used.

RESULTS

Thirty-nine patients were analyzed of which 74% were female. Exon 19 deletions (49%) and L858R point mutations (41%) were the most common EGFR mutations. Forty-nine percentage of patients were Eastern Cooperative Oncology Group 1. The median duration of osimertinib therapy was 6 months. The extracranial DCR and ORR were 60% and 54%, and the intracranial DCR and ORR were 68% and 53%, respectively. Median overall survival was 10.5 months (95% CI, 8.17 to 15.05 months).

CONCLUSION

There are limited treatment options for LMD in EGFR-positive lung cancer, and osimertinib at a dose of 80 mg daily is an active therapeutic option for these patients.

Erlotinib combined with bevacizumab and chemotherapy in first line osimertinib-resistant NSCLC patient with leptomeningeal metastasis: A case report

RATIONALE

Leptomeningeal metastasis (LM) is a fatal complication of advanced non-small cell lung cancer (NSCLC) with a poor prognosis. Osimertinib is a promising option for NSCLC with LM harboring epidermal growth factor receptor (EGFR) mutation. However, therapeutic approaches remain a challenge for osimertinib resistant NSCLCs with LM. Although studies have reported that the first/second-generation EGFR-tyrosine kinase inhibitors were active against osimertinib-resistant NSCLC with EGFR C797S and sensitive mutation (SM), the resistance inevitably occurred due to the development of the EGFR SM/C797S/T790M triple mutations.

PATIENT CONCERNS

A 48-year-old woman was diagnosed with stage IV lung adenocarcinoma harboring the EGFR mutation in the combination of chest computed tomography, biopsy and amplification refractory mutation system-polymerase chain. One year and a half after oral administration of osimertinib, the patient progressed to extensive LM.

DIAGNOSES

Magnetic resonance images of the brain showed extensive LM. Exfoliated tumor cells from cerebrospinal fluid (CSF) were positive detected by lumbar puncture and the cytology examination. EGFR mutations (exon19 E746_T751delinsI and exon20 C797S) in CSF circulating tumor DNA were detected by next-generation sequencing (NGS).

INTERVENTIONS

Pemetrexed (800 mg day 1), cis-platinum (40 mg day 1-3) combined with bevacizumab (400 mg day 1) every 3 weeks were administered to the patient. After 1 cycle, due to optic nerve invasion, erlotinib was applied 150 mg/d combined with previous regimen. The patient continued erlotinib monotherapy after 6 cycles.

OUTCOMES

After LM, erlotinib combined with pemetrexed, cis-platinum and bevacizumab were administered to the patient for 4.25 months based on the CSF NGS. Then, the patient continued erlotinib monotherapy and appeared disease progression after 10 months. The overall survival is 35 months.

LESSONS

LM is a fatal complication of advanced NSCLC with a poor prognosis. NGS profiling of CSF circulating tumor DNA is important in NSCLC patients with LM and erotinib plus bevacizumab and chemotherapy is a promising option for patients with LM harboring EGFR C797S/SM.

Evaluation of osimertinib for advanced non-small cell lung cancer with leptomeningeal metastases: a cost-effectiveness and budget impact analysis

Background Few regimens for non-small cell lung cancer (NSCLC) with leptomeningeal metastases (LM) patients exist up to date, most with low efficacy. A retrospective analysis showed that osimertinib significantly improved the overall survival of LM patients by 11.5 months (17.0 vs. 5.5) as compared to no osimertinib treatment. Until now, no pharmacoeconomic evaluation of osimertinib has been performed to determine its feasibility for widespread use in LM patients. Aim This study analyzed the cost-effectiveness of osimertinib in LM of NSCLC from the perspective of the Chinese health care system. Methods Based on a retrospective analysis from the Samsung Medical Center, a Markov model was constructed to estimate the lifetime benefits and costs for LM patients who were treated with osimertinib. The main outcomes were cost, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER). Sensitivity analyses were performed to verify the robustness of model. A budget impact analysis was conducted to estimate the annual incremental cost of osimertinib treatment. Results Compared with patients who were not treated with osimertinib, the survival time of patients treated with osimertinib was higher by 0.69 (1.24 vs. 0.55) QALYs. The incremental cost was $11,877 ($29,232 vs. $17,355) and the ICER was $17,214/QALY, which was below the willingness-to-pay threshold of $30,867/QALY. Osimertinib treatment will increase national cancer spending by $220 million in the first year and increase to $474 million in the fifth year. Conclusions Osimertinib treatment is deemed to be cost-effective for NSCLC with LM patients, however, its use would significantly increase annual cancer spending.

Rechallenge with previously administered epidermal growth factor receptor-tyrosine kinase inhibitors in EGFR-mutated non-small cell lung cancer with leptomeningeal metastasis

Objectives In EGFR-mutated non-small cell lung cancer (NSCLC) patients, approximately 80-90% of leptomeningeal metastasis (LM) develops after failed initial treatment with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (EGFR-TKI). However, the efficacy of rechallenging with previously administered EGFR-TKIs in patients with EGFR-mutated NSCLC and the LM that develops following EGFR-TKI treatment failure remains unknown. Materials and methods We retrospectively reviewed medical records of patients with EGFR-mutated NSCLC and LM, from November 2011 to August 2019. The patients were classified according to the LM treatment type: switched to previously unadministered EGFR-TKIs (Switch-TKI) or rechallenge with previously administered EGFR-TKIs (Rechallenge-TKI). Results In total, 50 patients treated with EGFR-TKI after LM diagnosis were included; 35 were treated with Switch-TKI and 15 with Rechallenge-TKI. The median overall survival (OS) from the time of LM diagnosis was 6.2 months in all study patients. According to the treatment type, the median OS from the time of LM diagnosis was 6.9 months in Switch-TKI patients and 4.9 months in Rechallenge-TKI patients. There was no significant difference in the OS between the Switch-TKI and Rechallenge-TKI groups (P = 0.864). Thirty-five patients were treated with erlotinib and 15 with osimertinib; Regardless of the type for EGFR-TKI, there was no significant difference in OS between patients treated with Switch-TKI and those treated with Rechallenge-TKI. Conclusion Rechallenge of previously administered EGFR-TKIs may be a therapeutic option for LM development after EGFR-TKI treatment failure in patients with EGFR-mutated NSCLC, not only switching to previously unadministered EGFR-TKIs.

Erlotinib as a salvage treatment after gefitinib failure for advanced non-small-cell lung cancer patients with brain metastasis: A successful case report and review

RATIONALE

The guidelines recommended gefitinib as a first-line targeted treatment for stage IV non-small-cell lung cancer (NSCLC) patients with EGFR mutations. However, resistance to gefitinib ensues invariably and there is little evidence as for the effectiveness of subsequent salvage treatment for patients without T790m mutation. The case is to evaluate the efficacy of erlotinib, another EGFR-TKI, after failed first-line use of gefitinib.

PATIENT CONCERNS

We described a 55-year-old man with good performance status (PS).

DIAGNOSES

He was histopathologically diagnosed stage IV lung adenocarcinoma with EGFR mutations in November 2018.

INTERVENTIONS

He was administrated with gefitinib daily (250 mg) for activating epidermal growth factor receptor (EGFR) mutations (exon 19 deletions,19del), and combined with platinum-based dual-drug chemotherapy. During the target treatments, the optimal efficacy evaluation was partial remission (PR) with a 12-month progression-free survival (PFS) time. Later, the intracranial progression of the patient rendered the treatment change to erlotinib.

OUTCOMES

It is surprising that the tumor lesion in brain as well as lung relieved obviously. His progression-free survival (PFS)was nearly 11 months, and the overall survival (OS)was>36 months up to now. The adverse events were tolerable.

LESSIONS

This case manifests that re-biopsy of advanced or recurrent NSCLC is beneficial to make a better therapeutic regimen, and erlotinib can be used as a salvage treatment after gefitinib failure.

LncRNA TINCR favors tumorigenesis via STAT3-TINCR-EGFR-feedback loop by recruiting DNMT1 and acting as a competing endogenous RNA in human breast cancer

The long noncoding RNA (lncRNA) TINCR has recently been found to be associated with the progression of human malignancies, but the molecular mechanism of TINCR action remains elusive, particularly in breast cancer. The oncogenic role of TINCR was examined in vitro and in vivo in breast cancer. Next, the interaction between TINCR, DNMT1, and miR-503-5p methylation was explored. Moreover, the mechanism by which TINCR enhances EGFR expression and downstream signaling via an RNA–RNA interaction was comprehensively investigated. Furthermore, upstream transcriptional regulation of TINCR expression by STAT3 was examined by performing chromatin immunoprecipitation. Finally, feedback signaling in the STAT3–TINCR–EGFR downstream cascade was also investigated. TINCR is upregulated in human breast cancer tissues, and TINCR knockdown suppresses tumorigenesis in vitro and in vivo. Mechanistically, TINCR recruits DNMT1 to the miR-503-5p locus promoter, which increases the methylation and suppresses the transcriptional expression of miR-503-5p. Furthermore, TINCR also functions as a competing endogenous RNA to upregulate EGFR expression by sponging miR-503-5p. In addition, TINCR stimulates JAK2–STAT3 signaling downstream from EGFR, and STAT3 reciprocally enhances the transcriptional expression of TINCR. Our findings broaden the current understanding of the diverse manners in which TINCR functions in cancer biology. The newly identified STAT3–TINCR–EGFR-feedback loop could serve as a potential therapeutic target for human cancer.

Central nervous system metastases and oligoprogression during treatment with tyrosine kinase inhibitors in oncogene-addicted non-small cell lung cancer: how to treat and when?

Up to 70% of non-small cell lung cancer (NSCLC) patients develop central nervous system (CNS) metastases during the course of their disease, especially those with oncogenic drivers treated with a first-generation tyrosine kinase inhibitor (TKI), because of the relatively poor CNS penetration. CNS metastases are associated with a negative impact on quality of life and survival. As, with the introduction of newer generation TKIs, the survival rates are increasing in this particular population, treatment and/or prevention of CNS metastases becomes even more relevant and the TKI with the best CNS efficacy should be selected. Unfortunately, CNS efficacy data in clinical trials are not fully comparable. Furthermore, oligoprogression to the brain without extracranial progression regularly occurs in the oncogenic driver population and both local therapy and switch of systemic therapy are possible treatment options. However, the best order of systemic and local therapy is still not precisely known. In this narrative review, we will summarize incidence and treatment of CNS metastases in oncogene driven NSCLC, including the optimal treatment of CNS oligometastatic disease (synchronous as well as oligoprogressive).

Remarkable response to dacomitinib in a patient with leptomeningeal carcinomatosis due to EGFR-mutant non-small cell lung cancer

Dacomitinib, a second‐generation epidermal growth factor receptor (EGFR)‐tyrosine kinase inhibitor, is a standard therapeutic option for patients with EGFR‐mutant non‐small cell lung cancer (NSCLC). However, its efficacy in patients with central nervous system lesions is unclear. Here, we describe a case of EGFR‐mutant NSCLC whose neurological symptoms were due to leptomeningeal carcinomatosis that was successfully treated with dacomitinib. After initiation of dacomitinib, the neurological symptoms of the patient were remarkably improved and leptomeningeal dissemination and brain metastases were shown to have regressed on magnetic resonance imaging (MRI) scan. To our knowledge, this is the first report showing the efficacy of dacomitinib in a patient with leptomeningeal carcinomatosis due to EGFR‐mutant NSCLC. The current case suggests that dacomitinib is a novel treatment option for patients with EGFR‐mutant NSCLC accompanied by central nervous system lesions, even those with symptomatic leptomeningeal carcinomatosis.

Key points

Significant findings of the study

This is the first report showing the efficacy of dacomitinib in a patient with leptomeningeal carcinomatosis due to EGFR‐mutant NSCLC.

What this study adds

The current case suggests that dacomitinib is a novel treatment option for patients with EGFR‐mutant NSCLC accompanied by CNS lesions, even in those with symptomatic leptomeningeal carcinomatosis.

[Management of Drug Therapy for Leptomeningeal Metastasis of Sensitive Driver Gene Positive Non-small Cell Lung Cancer]

Leptomeningeal metastasis (LM) is one of the serious complications of advanced non-small cell lung cancer (NSCLC), although the incidence is not high, the clinical symptoms are severe and the prognosis is poor. LM is prone to occur in patients with positive driver gene than negative. At present, the treatment of LM mainly includes molecular targeted therapy, systemic chemotherapy, whole brain radiotherapy, intrathecal chemotherapy and immunotherapy. Although there are many treatments, the efficacy of LM is still unsatisfactory. This article reviews the drug therapy of sensitive driver gene positive NSCLC LM.

Whole brain radiotherapy (WBRT) for leptomeningeal metastasis from NSCLC in the era of targeted therapy: a retrospective study

Background and purpose

Leptomeningeal metastasis (LM) is a rare but detrimental complication in patients with non-small cell lung cancer (NSCLC). Although whole brain radiotherapy (WBRT) is used to eliminating cancer cells or microscopic foci, it is becoming less favorable due to the concerns over neurocognitive toxicity. This study aimed to re-evaluate the role of WBRT in the setting of modern targeted therapy.

Materials and methods

From December 2014 to March 2019, 80 NSCLC patients with cytologically and/or radiologically proven LM diagnosis were retrospectively analyzed.

Results

The median OS (mOS) after diagnosis of LM was 8.0 (95%CI: 4.4 to 11.6) months, and the one-year OS was 39.4%. The mOS for EGFR-mutated LM patients was 12.6 (3.0 to 22.2) months versus only 4.1 (2.8 to 5.4) for patients with wild-type EGFR (P < 0.001). Younger patients (< 53.5 yrs.) appeared to have a better OS than older patients (≥53.5 yrs.) (12.6 vs. 6.1, P = 0.041). No survival benefits were found in EGFR-mutated patients who received WBRT (P = 0.490). In contrast, mOS was significantly prolonged in wild-type EGFR patients with WBRT versus non-WBRT (mOS: 8.0 vs. 2.1, P = 0.002). Multivariate analysis indicated that WBRT (P = 0.025) and younger age (P = 0.048) were independent prognostic factors that predicted prolonged survival for wild-type EGFR LM patients from NSCLC.

Conclusion

Our study demonstrated that WBRT has clear survival advantages for patients with wild-type EGFR, and molecular biological stratification of LM patients for WBRT is highly recommended.

Management of leptomeningeal carcinomatosis and challenges of trial design

PURPOSE OF REVIEW

Highlight recent data in lung and breast cancer leptomeningeal disease and address clinical trials that are open for patients.

RECENT FINDINGS

Patients with lung and breast cancer leptomeningeal disease have survival outcomes of less than 1 year, despite advances in treatment strategy. Efforts to develop liquid biopsy biomarkers of disease progression from cerebrospinal fluid and plasma are underway. There are over 10 clinical trials open for patients with leptomeningeal disease, half of which use immunotherapy.

SUMMARY

Consortium-based, multicenter clinical trials for patients with leptomeningeal disease are urgently needed to expand the treatment armamentarium.

Osimertinib for Patients With Leptomeningeal Metastases Associated With EGFR T790M-Positive Advanced NSCLC: The AURA Leptomeningeal Metastases Analysis

INTRODUCTION

Osimertinib has shown promising activity in patients with leptomeningeal metastases (LMs) of EGFR-positive NSCLC at 160 mg once daily (qd) (BLOOM; NCT02228369). We report LM activity with osimertinib (80 mg qd) in a retrospective analysis of studies across the AURA program (AURA extension, AURA2, AURA17, and AURA3).

METHODS

Patients with EGFR T790M-positive advanced NSCLC and progression after previous EGFR-tyrosine kinase inhibitor therapy received osimertinib (80 mg qd). Patients with central nervous system (CNS) metastases (including LMs) were eligible if the lesions were neurologically asymptomatic and stable. Patients with evidence of LMs at the study entry were retrospectively included for the analysis; brain scans were assessed for radiologic LM response by neuroradiologically blinded, independent central review per the modified Response Assessment in Neuro-Oncology LM criteria. LM objective response rate, duration of response, progression-free survival, and overall survival were assessed. A longitudinal analysis was performed to investigate the relationship between changes from the baseline in non-CNS tumor sizes and LM responses at each visit of patients in AURA LM and BLOOM studies.

RESULTS

For the 22 patients included in the analysis, LM objective response rate was 55% (95% confidence interval [CI]: 32-76). Median LM duration of response was not reached (95% CI: 2.8-not calculable [NC]). Median LM progression-free survival and overall survival were 11.1 months (95% CI: 4.6-NC) and 18.8 months (95% CI: 6.3-NC), respectively. The longitudinal analysis revealed similar non-CNS and LM responses between the patients in AURA LM and BLOOM programs.

CONCLUSIONS

Patients with EGFR T790M-positive NSCLC and radiologically detected LM obtained clinical benefit from osimertinib (80 mg qd).

Dramatic Response of Leptomeningeal Carcinomatosis to Nivolumab in PD-L1 Highly Expressive Non-small Cell Lung Cancer: A Case Report

In a patient who had been diagnosed of located squamous cell lung carcinoma, pneumonectomy, and adjuvant chemotherapy were performed. Brain recurrence and subsequent lung metastatic disease were uncontrolled by neurosurgery, holocranial radiotherapy, and first-line chemotherapy. In August 2015, appearance of leptomeningeal carcinomatosis triggered severe clinical deterioration and threatened the patient's life. Anti-PD1 immune checkpoint inhibitor Nivolumab was initiated in an attempt to stop tumor growth, achieving a spectacular brain and pulmonary complete response and clinical improvement, without serious adverse effects. High expression PD-L1 level (100%) was found in the pathological tissue sample. Nivolumab was maintained for more than 2 years and stopped in December 2017 after 28 months of treatment, with no disease evidence. More than 3 years after its onset, the patient maintains an outstanding PS with complete tumor response and no evidence of disease in last surveillance CT scan and brain MRI.