Erlotinib for whole-brain-radiotherapy-refractory leptomeningeal metastases after gefitinib failure in a lung adenocarcinoma patient

Osimertinib is associated with improved outcomes in pre-treated non-small cell lung cancer leptomeningeal metastases: A systematic review and meta-analysiss

Purpose

Leptomeningeal metastasis (LM) is a severe complication of non-small cell lung cancer (NSCLC). In patients with NSCLC LM harboring epidermal growth factor receptor (EGFR) mutations, osimertinib is favored over alternative EGFR tyrosine kinase inhibitors (TKIs). However, the efficacy of osimertinib relative to other EGFR-TKIs is not well established for patients with LM. We aimed to compare the efficacy of EGFR-TKIs in EGFR-mutated NSCLC LM.

Methods

This systematic review and meta-analysis performed according to PRISMA guidelines included studies of adult patients with EGFR-mutated NSCLC and a diagnosis of LM who received an EGFR-TKI for the treatment of LM. We searched Medline ALL, Embase, Cochrane Central Register of Controlled Trials, Scopus, and Web of Science Core Collection. The evaluation of biases was done by using the Ottawa-Newscastle scale. The hazard ratio was used as the parameter of interest for overall survival (OS) and central nervous system-specific progression-free survival (PFS).

Results

128 publications were included with 243 patients and 282 lines of EGFR-TKI for NSCLC LM that met inclusion criteria. The median PFS in patients receiving any EGFR-TKI was 9.1 months, and the median OS was 14.5 months. In univariate analyses of the entire cohort, osimertinib treatment demonstrated significantly prolonged PFS, but not OS, compared to other EGFR-TKIs. Osimertinib demonstrated significantly prolonged PFS and OS in the subset of patients who were previously treated with EGFR-TKIs, but not in EGFR-TKI naïve patients.

Conclusion

Osimertinib is associated with improved outcomes compared to other EGFR-TKIs, particularly in patients previously treated with EGFR-TKIs. An important limitation is that most patients were derived from retrospective reports. These results highlight the need for prospective studies for this difficult-to-treat patient population.

First-line osimertinib for leptomeningeal metastasis from lung adenocarcinoma with EGFR mutation as the initial and solitary site of postoperative recurrence

Leptomeningeal metastasis (LM) from lung cancer has poor prognosis, and effective therapy has not been established. We present the case of a 54-year-old man with LM from lung adenocarcinoma harboring EGFR L858R point mutation, who received osimertinib as first-line therapy. He had previously undergone left lower lobectomy and lymph node dissection for lung adenocarcinoma. Five years and 9 months after the operation, he developed symptoms of dizziness, lightheadedness, and headache. Magnetic resonance imaging showed high signal intensity in the cerebral sulcus and meninges, and cerebrospinal fluid (CSF) cytology indicated adenocarcinoma with EGFR L858R point mutation, which suggested LM. After CSF drainage and administration of corticosteroid and glycerol, the patient received osimertinib (80 mg/day) as first-line therapy. These symptoms including dizziness, lightheadedness, and headache were relieved and the MRI appearance was normal, and he survived for 19 months with no disease progression. Osimertinib is considered to be an effective therapeutic option for LM from lung adenocarcinoma harboring EGFR mutation.

Leptomeningeal metastasis

Leptomeningeal metastasis (LM) results from dissemination of cancer cells to both the leptomeninges (pia and arachnoid) and cerebrospinal fluid (CSF) compartment. Breast cancer, lung cancer, and melanoma are the most common solid tumors that cause LM. Recent approval of more active anticancer therapies has resulted in improvement in survival that is partly responsible for an increased incidence of LM. Neurologic deficits, once manifest, are mostly irreversible, and often have a significant impact on patient quality of life. LM-directed therapy is based on symptom palliation, circumscribed use of neurosurgery, limited field radiotherapy, intra-CSF and systemic therapies. Novel methods of detecting LM include detection of CSF circulating tumor cells and tumor cell-free DNA. A recent international guideline for a standardization of response assessment in LM may improve cross-trial comparisons as well as within-trial evaluation of treatment. An increasing number of retrospective studies suggest that molecular-targeted therapy, such as EGFR and ALK inhibitors in lung cancer, trastuzumab in HER2+ breast cancer, and BRAF inhibitors in melanoma, may be effective as part of the multidisciplinary management of LM. Prospective randomized trials with standardized response assessment are needed to further validate these preliminary findings.

[Research progress of lung cancer with leptomeningeal metastasis]

脑膜转移是肺癌最严重的并发症之一，患者预后极差。脑膜转移患者临床表现缺乏特异性，主要表现为脑、脑神经、脊神经受累症状。目前诊断主要依据肿瘤病史、临床症状、增强核磁共振（magnetic resnance image, MRI）扫描和脑脊液细胞学检查。近年来新的检测方式在临床上不断涌现，明显提高了脑膜转移的早期发现率，但肺癌脑膜转移的综合治疗疗效仍不令人满意。本文就肺癌脑膜转移的病理生理、临床表现、诊断方法及治疗疗效的研究进展做一综述。

EGFR-TKI therapy for patients with brain metastases from non-small-cell lung cancer: a pooled analysis of published data

Introduction

Brain metastases are one of the leading causes of death from non-small-cell lung cancer (NSCLC). The use of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) to treat brain metastases remains controversial. Thus, we performed a pooled analysis of published data to evaluate the efficacy of EGFR-TKIs in NSCLC patients with brain metastases, particularly for tumors with activating EGFR mutations.

Methods

Several data sources were searched, including PubMed, Web of Science, and ASCO Annual Meetings databases. The end points were intracranial overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and adverse events. The pooled ORR, DCR, PFS, and OS with 95% confidence intervals (CIs) were calculated employing fixed- or random-effect models, depending on the heterogeneity of the included studies.

Results

Sixteen published studies were included in this analysis, with a total of 464 enrolled patients. The EGFR mutational status was unknown for 362 (unselected group), and 102 had activating EGFR mutations. The pooled intracranial ORR and DCR were 51.8% (95% CI: 45.8%–57.8%) and 75.7% (95% CI: 70.3%–80.5%), respectively. A higher ORR was observed in the EGFR mutation group than in the unselected group (85.0% vs 45.1%); a similar trend was observed for the DCR (94.6% vs 71.3%). The pooled median PFS and OS were 7.4 months (95% CI, 4.9–9.9) and 11.9 months (95% CI, 7.7–16.2), respectively, with longer PFS (12.3 months vs 5.9 months) and OS (16.2 months vs 10.3 months) in the EGFR mutation group than in the unselected group.

Conclusion

This pooled analysis strongly suggests that EGFR-TKIs are an effective treatment for NSCLC patients with brain metastases, particularly in those patients harboring EGFR mutations. Larger prospective randomized clinical trials are warranted to confirm our conclusion and identify the most appropriate treatment model.

Carcinomatous meningitis: Leptomeningeal metastases in solid tumors

Leptomeningeal metastasis (LM) results from metastatic spread of cancer to the leptomeninges, giving rise to central nervous system dysfunction. Breast cancer, lung cancer, and melanoma are the most frequent causes of LM among solid tumors in adults. An early diagnosis of LM, before fixed neurologic deficits are manifest, permits earlier and potentially more effective treatment, thus leading to a better quality of life in patients so affected. Apart from a clinical suspicion of LM, diagnosis is dependent upon demonstration of cancer in cerebrospinal fluid (CSF) or radiographic manifestations as revealed by neuraxis imaging. Potentially of use, though not commonly employed, today are use of biomarkers and protein profiling in the CSF. Symptomatic treatment is directed at pain including headache, nausea, and vomiting, whereas more specific LM-directed therapies include intra-CSF chemotherapy, systemic chemotherapy, and site-specific radiotherapy. A special emphasis in the review discusses novel agents including targeted therapies, that may be promising in the future management of LM. These new therapies include anti-epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors erlotinib and gefitinib in nonsmall cell lung cancer, anti-HER2 monoclonal antibody trastuzumab in breast cancer, anti-CTLA4 ipilimumab and anti-BRAF tyrosine kinase inhibitors such as vermurafenib in melanoma, and the antivascular endothelial growth factor monoclonal antibody bevacizumab are currently under investigation in patients with LM. Challenges of managing patients with LM are manifold and include determining the appropriate patients for treatment as well as the optimal route of administration of intra-CSF drug therapy.