Leptomeningeal carcinomatosis in non-small cell lung cancer patients: A continuing challenge in the personalized treatment era

Evaluating Circulating Tumor DNA From the Cerebrospinal Fluid of Patients With Melanoma and Leptomeningeal Disease

Circulating tumor DNA (ctDNA) refers to tumor-derived cell-free DNA that circulates in body fluids. Fluid samples are easier to collect than tumor tissue, and are amenable to serial collection at multiple time points during the course of a patient's illness. Studies have demonstrated the feasibility of performing mutation profiling from blood samples in cancer patients. However, detection of ctDNA in the blood of patients with brain tumors is suboptimal. Cerebrospinal fluid (CSF) can be obtained via lumbar puncture or intraventricular catheter, and may be a suitable fluid to assess ctDNA in patients with brain tumors. We detected melanoma-associated mutations by droplet-digital PCR (ddPCR) and next-generation sequencing in ctDNA obtained from the CSF (CSF-ctDNA) of melanoma patients with leptomeningeal disease. There is a strong correlation between mutation detection by ddPCR, the presence of circulating tumor cells in CSF and abnormalities in the MRI. However, approximately 30% of CSF samples that were negative or indeterminate for the presence of tumor cells by microscopic examination were positive for CSF-ctDNA by ddPCR. Our results demonstrate that CSF is a suitable fluid for evaluating ctDNA and ddPCR is superior to CSF-cytology for analysis of CSF in melanoma patients with leptomeningeal disease.

Metastasis manners and the underlying mechanisms of ALK and ROS1 rearrangement lung cancer and current possible therapeutic strategies

The rearrangements of anaplastic lymphoma kinase (ALK) and the c-ros oncogene 1 (ROS1) have both been important driving factors in non-small-cell lung cancer (NSCLC). They have already been defined in 3-5% of NSCLC patients. ALK and ROS1 rearrangements are associated with unique clinical and pathological features, especially patients are usually younger, with milder or never smoking history, and adenocarcinoma histology. Also, they have both been found to contribute to the metastasis of NSCLC by cell migration and invasion. It has recently been recognized that the brain can be considered as a primary site for metastasis in cancers with ALK or ROS1 rearrangements. The present review summarizes the current status of NSCLC metastasis and possible mechanisms based on available evidence, and then we list possible therapeutic strategies so that an increase in control of ALK and ROS1 rearrangement of NSCLC metastases by combination therapy can be translated in an increase in overall survival and prognosis.

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.

The clinical characteristic and prognostic factors of leptomeningeal metastasis in patients with non-small-cell lung cancer-a retrospective study from one single cancer institute

Background

Leptomeningeal metastasis (LM) is a detrimental complication of advanced non‐small‐cell lung cancer (NSCLC), and the optimal therapeutic approach for LM patients is in shortage. This retrospective study aimed to investigate the clinical features and prognostic factors of NSCLC patients with LM.

Methods

We retrospectively reviewed the medical records of NSCLC patients with LM at the Shandong Cancer Hospital and Institute between July 2014 and March 2018. Identified cases had pathology‐proven NSCLC with either positive cerebrospinal fluid cytology or leptomeningeal enhancement by MRI.

Results

One hundred and thirty‐six NSCLC patients (58 men, 78 women) with LM were enrolled in the retrospective study; median age was 55 years (range, 29‐89 years). Fifty‐one patients harbored EGFR mutations, ALK rearrangement was detected in 6 patients. Treatment for LM consisted of EGFR‐TKIs alone in 11 patients, whole brain radiotherapy (WBRT) alone in 19 patients, Chemotherapy (ChT) alone in 12 patients, EGFR‐TKIs plus WBRT in 30 patients, WBRT plus ChT in 25 patients, and EGFR‐TKIs plus ChT in 24 patients. The median progression‐free survival was 3.9 months (95% confidence interval [CI]: 3.178‐4.622), and the median overall survival (OS_LM) was 9.8 months (95% CI:7.5‐12.1). Thirty patients who received WBRT plus EGFR‐TKIs achieved longer survival than those who only received WBRT (median 13.6 vs 8.8 months; P = 0.027), but did not add any survival benefit than those only received EGFR‐TKIs (median 13.6 vs 13.9 months; P = 0.352). A multivariate analysis indicated that KPS ≥ 80 (hazard ratio [HR] = 0.592, 95% CI:0.369‐0.95; P = 0.03) and EGFR‐TKIs (HR = 0.507, 95% CI:0.283‐0.908; P = 0.022) after LM diagnosis were independent favourable predictors of survival, whereas smoking (HR = 1.181, 95% CI:1.009‐3.246; P = 0.047) was an independent predictor of poor survival.

Conclusions

Our results suggest that patients with good performance statuses, non‐smoking patients, and the administration of EGFR‐TKIs might improve clinical outcomes in NSCLC patients with LM.

A molecular graded prognostic assessment (molGPA) model specific for estimating survival in lung cancer patients with leptomeningeal metastases

OBJECTIVES

Leptomeningeal metastases (LM) had increased in advanced non-small-cell lung cancer (NSCLC) over the last 10 years. The survival outcome remained overall poor, heterogeneous and was reported in association with genotypes in lung cancer patients with LM. Graded prognostic assessment model integrated with molecular alterations (molGPA) might be accurate for outcome prediction of LM patients, but needs to be established.

MATERIALS AND METHODS

We retrospectively screened 8921 consecutive lung cancer patients from January 2011 to March 2018. A total of 301 patients diagnosed as LM were enrolled, and randomly divided into training and validation sets after stratified by gender and age. A molGPA score for each patient was calculated based on the weighted significant parameters including gene mutations.

RESULT

The median OS for the 301 patients was 9.2 months (95%CI: 7.9-10.5). In the training set, EGFR/ALK positivity, Karnofsky performance score (KPS) score≥60 and absence of extracranial metastasis (ECM) independently predicted better OS. We developed a molGPA model based on above significant prognostic factors. This molGPA model classified LM patients into three prognosis groups of high, intermediate and low risk (molGPA score of 0, 0.5-1.0 and 1.5-2.0, respectively. The median OS of high, intermediate and low risk LM patients in the training set was 0.3, 3.5 and 15.9 months, respectively (p < 0.001). In the validation set, the median OS was 0.9, 5.8 and 17.7 months in the three molGPA subgroups, accordingly (p < 0.001). The C-index of this model in training and validation sets was 0.70 (95%CI: 0.66-0.73) and 0.64 (95%CI: 0.58-0.70) respectively.

CONCLUSION

The LM molGPA model with integration of gene status, KPS and ECM can accurately classify lung cancer patients with LM into diverse prognosis.

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.

Cerebrospinal fluid cell-free tumour DNA as a liquid biopsy for primary brain tumours and central nervous system metastases

Challenges in obtaining tissue specimens from patients with brain tumours limit the diagnosis and molecular characterisation and impair the development of better therapeutic approaches. The analysis of cell-free tumour DNA in plasma (considered a liquid biopsy) has facilitated the characterisation of extra-cranial tumours. However, cell-free tumour DNA in plasma is limited in quantity and may not reliably capture the landscape of genomic alterations of brain tumours. Here, we review recent work assessing the relevance of cell-free tumour DNA from cerebrospinal fluid in the characterisation of brain cancer. We focus on the advances in the use of the cerebrospinal fluid as a source of cell-free tumour DNA to facilitate diagnosis, reveal actionable genomic alterations, monitor responses to therapy, and capture tumour heterogeneity in patients with primary brain tumours and brain and leptomeningeal metastases. Profiling cerebrospinal fluid cell-free tumour DNA provides the opportunity to precisely acquire and monitor genomic information in real time and guide precision therapies.

Clinical Utility of Cerebrospinal Fluid Cell-Free DNA as Liquid Biopsy for Leptomeningeal Metastases in ALK-Rearranged NSCLC

INTRODUCTION

Leptomeningeal metastases (LMs) indicated a poor prognosis in NSCLC. LMs were more frequent in driver gene-mutated patients, and cerebrospinal fluid (CSF) cell-free DNA has shown unique genetic profiles of LM in EGFR-mutated LM. However, studies in patients with ALK receptor tyrosine kinase gene (ALK)-rearranged NSCLC with LMs are scarce.

METHODS

Patients with lung cancer with ALK rearrangement were screened from September 2011 to February 2018 at our institute. CSF and paired plasma were tested by next-generation sequencing.

RESULTS

LMs were diagnosed in 30 (10.3%) of 291 patients with ALK-rearranged lung cancer. A total of 11 paired CSF and plasma samples tested by next-generation sequencing were analyzed. Driver genes were detected in 81.8% of the CSF samples (9 of 11) and 45.5% of the plasma samples (5 of 11) (p = 0.183). The maximum allelic fractions were all higher in CSF than in plasma (p = 0.009). ALK and tumor protein p53 gene (TP53) were the two most frequently mutated genes in CSF. Gatekeeper gene ALK G1202R and C1156F mutations were identified in CSF after resistance to alectinib. Multiple copy number variants were mainly found in CSF, including in EGFR, cyclin D1 gene (CCND1), fibroblast growth factor 3 gene (FGF3), and fibroblast growth factor 4 gene (FGF4). Also found were v-myc avian myelocytomatosis viral oncogene homolog gene (MYC) copy number gains and TP53 and cyclin dependent kinase inhibitor 2A gene (CDKN2A) copy number deletions. Brigatinib seemed to be effective in controlling LM. One case showed that CSF could be used to monitor disease development of LM and longitudinally monitor tumor response.

CONCLUSION

Liquid biopsy of CSF is more sensitive than liquid biopsy of plasma to detect targetable alterations, characterizing resistance mechanisms on progression and monitoring tumor response in patients with ALK-rearranged NSCLC with LM. Thus, CSF might be promising as a medium of liquid biopsy in LM.

Safety of osimertinib in EGFR-mutated non-small cell lung cancer

INTRODUCTION

Osimertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), specifically designed to inhibit EGFR sensitizing and T790M acquired mutations, minimizing exposure in EGFR-wild-type tissues. Areas covered: Osimertinib use in EGFR-mutated non-small cell lung cancer patients is described, focusing on safety and tolerability from studies supporting its approval. Expert opinion: Osimertinib demonstrated greater efficacy, including CNS activity, compared to chemotherapy, with a manageable safety profile in pretreated T790M+ EGFR-mutated patients, leading to FDA approval in 2015 within record time in the oncology field. However, the therapeutic strategy in the EGFR-mutated population is changing, following the FLAURA study in untreated EGFR-mutated patients, in which osimertinib improved progression-free survival compared to other TKIs, with a similar toxicity profile but a lower serious adverse event rate. In April 2018, the FDA and EMA approved osimertinib as first-line therapy for EGFR-mutated patients. Long-term survival data will ultimately establish the true benefit of upfront versus sequential strategies guided by T790M status. These studies favor osimertinib for tolerability and safety, except for the slightly higher rate of interstitial lung disease, but which was nonetheless manageable. In the coming years, osimertinib will be consolidated as standard therapy in the EGFR population and in naïve and pretreated patients, based on mature survival data and the toxicity profile.

Leptomeningeal metastases in non-small-cell lung cancer

Leptomeningeal metastasis is a complication of advanced non-small-cell lung cancer (NSCLC). Diagnosis and monitoring of leptomeningeal metastasis are challenging, and are based on neurological, radiographic, and cerebrospinal fluid findings. Substantial progress has been made in several key aspects of management of leptomeningeal metastasis, including improved characterisation of the genetic profiles, generation of clinically relevant animal models, advances in cerebrospinal fluid liquid biopsy with improved cytology and genotyping analysis, and the development of therapeutic agents with greater CNS penetration. This Review discusses cumulative data on multiple treatment modalities with a particular focus on recent advances in molecularly targeted therapies in subtypes of patients with leptomeningeal metastasis from NSCLC. Future research is needed to further understand the biology of leptomeningeal metastasis and the mechanisms of resistance to treatment.

Leptomeningeal metastasis after effective first-generation EGFR TKI treatment of advanced non-small cell lung cancer

OBJECTIVE

To evaluate the influence of a first-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI) treatment on the clinical features of leptomeningeal metastasis (LM) progression and outcome in advanced non-small cell lung cancer (NSCLC) patients.

METHODS

We retrospectively evaluated advanced NSCLC patients receiving effective first-generation EGFR TKI treatment (e.g., treatment > 6 months) at our institution between January 2008 and February 2014. Incidence, time to progression, and treatment outcome of LM were examined.

RESULTS

In our cohort, 29/420 patients (6.9%) developed LM. Among the patients harboring L858R or deletion of exon 19 in EGFR, the incidence of LM was 10.7% (21/197) and 3.4% (7/203), respectively (P = 0.006). The median time to LM progression was 16.5 months (95% confidence interval (CI), 11.9-20.8). The median overall survival (OS) after LM diagnosis was 5.2 months (95% CI, 3.2-7.2). In a subgroup analysis, OS was improved in patients with performance status (PS) ≤ 2 vs. PS > 2 (14.2 months vs. 2.3 months, respectively; P < 0.001). OS was also improved among patients who received, rather than did not receive, anti-tumor treatment (6.0 months vs. 1.9 months, respectively; P < 0.001) or whole brain radiotherapy (WBRT) (6.0 months vs. 3.9 months, respectively; P = 0.038). Multivariate analysis indicated that WBRT is a good prognostic factor (P = 0.048), whereas best support care (P = 0.033) and PS > 2 (P = 0.034) were poor prognostic factors.

CONCLUSION

A greater incidence of LM was observed in NSCLC patients harboring EGFR mutations after effective EGFR TKI treatment. In particular, the primary mutation, L858R, potentially predicts a higher risk of LM compared with deletion of exon 19. These results highlight the importance of determining mutation status when evaluating the biological behavior of LM in NSCLC patients who positively respond to EGFR TKI treatment.

Unique genomic profiles obtained from cerebrospinal fluid cell-free DNA of non-small cell lung cancer patients with leptomeningeal metastases

BACKGROUND

Leptomeningeal metastases (LM), associated with poor prognosis, are frequent complications of advanced non-small cell lung cancer (NSCLC) patients, especially in patients with epidermal growth factor receptor (EGFR) mutations. Due to limited access to leptomeningeal lesions, the mutational landscape of LM has not been comprehensively investigated in large cohorts and the underlining biology of LM remains elusive. Some studies have explored the potential of cerebrospinal fluid (CSF) in reflecting the molecular profile of LM but with limited number of patients enrolled.

METHODS

In this study, we performed capture-based targeted sequencing using a panel consisting of 168 lung cancer-related genes on matched CSF and plasma samples from 72 advanced NSCLC patients with confirmed LM to interrogate the potential of CSF as a source of liquid biopsy.

RESULTS

We revealed a rate of detection of 81.5% and 62.5% for CSF and plasma, respectively (p = 0.008). The maximum allelic fraction (MaxAF) was also significantly higher in CSF (43.6% vs. 4.6%) (p < 0.001). CSF, harboring a unique genomic profile by having a significant number of CSF-specific mutations, primarily copy number variations, is superior to plasma in reflecting the mutational profile of LM. Further pathway enrichment analysis revealed that most of CSF-specific mutations participated in pathways relevant to the tumorigenesis and the development of metastases. Moreover, our data also revealed that TP53 loss of heterozygosity (LOH) predominantly existed in CSF (p < 0.001).

CONCLUSIONS

Collectively, we demonstrated that CSF provides a more comprehensive profile of LM than plasma in a large cohort, thus can be used as an alternative source of liquid biopsy for LM patients.

Non-small cell lung cancer leptomeningeal metastases treated with intrathecal therapy plus osimertinib and temozolomide and whole-brain radiation therapy: a case report

RATIONALE

Leptomeningeal metastasis (LM) is an important cause of mortality in patients with non-small cell lung cancer (NSCLC). As the symptoms of LM and its early clinical manifestations are nonspecific, early diagnosis of LM is difficult. However, there are few treatment options for LM, which leads to a poor prognosis; thus, increased clinical attention is necessary. The effects of most systemic chemotherapies on metastatic brain tumors (brain metastases and LMs) are limited as they cannot pass the blood-brain barrier; therefore, whole-brain radiation therapy is a therapeutic option. Osimertinib is a potent and irreversible third-generation oral epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). It binds to EGFR with high affinity when the EGFR T790M mutation is present together with sensitizing mutations. The clinical efficacy of osimertinib in NSCLC patients carrying the T790M mutation has been demonstrated in clinical trial NCT02468661. Intrathecal injection of chemotherapeutic drugs can be directed to a specific lesion. Temozolomide is one such drug, and its effect has been confirmed.

PATIENT AND INTERVENTIONS

We treated a 38-year-old patient with NSCLC who carried the EGFR L858R mutation. We administered a combination of oral osimertinib and oral temozolomide plus an intrathecal injection of cytarabine and whole-brain radiation therapy for symptomatic multiple brain metastases.

OUTCOMES

The patient showed a marked response to this combination therapy. To date (after ~18 months), no recurrence or new lesions have been observed and he is asymptomatic. His disease-free survival surpasses that achieved with any monotherapy for LM.

LESSONS

This is the first report to demonstrate the response to combination therapy in an NSCLC patient with LM. These findings indicate the potential utility of chemotherapy combined with radiotherapy combined with targeted therapy combined with local treatment, as each treatment acts via a different mechanism, enhancing their therapeutic effects.

Intracranial Response to Anti-Programmed Death 1 Therapy in a Patient with Metastatic Non-Small Cell Lung Cancer with Leptomeningeal Carcinomatosis

Central nervous system metastasis in non-small cell lung cancer remains a therapeutic challenge and confers a poor prognosis. Here we describe a patient with lung adenocarcinoma, parenchymal brain metastases, and leptomeningeal carcinomatosis who demonstrated a sustained response to programmed death 1 inhibition combined with stereotactic radiosurgery.

Great efficacy of bevacizumab plus erlotinib for leptomeningeal metastases from non-small cell lung cancer with initially positive EGFR mutation: a case report

Leptomeningeal metastases (LMs) were devastating metastatic complications of non-small cell lung cancer (NSCLC). Management of LMs relied on conventional therapy but with poor survival, lacking effective treatment strategies. We present the case of a 52-year-old female non-smoker with advanced lung adenocarcinoma and initially positive EGFR-mutation, who failed to the treatment of standard first-line chemotherapy (pemetrexed plus cisplatin) and bevacizumab (BEV), and maintenance therapy with pemetrexed plus BEV. Under the progression-free survival of 6 months, suffered from LMs, then erlotinib combined with BEV were delivered, and symptoms were significantly alleviated, remained stable and even relieved slightly for at least 18 months. The combination of bevacizumab and erlotinib could be an optional effective management strategy for patients with LMs from NSCLC and harboring EGFR-mutation.

Management of Leptomeningeal Metastases in Non-oncogene Addicted Non-small Cell Lung Cancer

Brain metastases in non-small cell lung cancer (NSCLC) patients are more often detected due to imaging modalities improvements but also emerge because of improved treatments of the primary tumor which lead to a longer survival. In this context, development of leptomeningeal metastases (LM) is a devastating complication and its prognosis remains poor despite advances in systemic and local approaches. Histology characterization of NSCLC and molecular expression influence LM management. For those with “oncogene addiction,” new generation epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKIs) were developed to strongly penetrate the blood-brain barrier (BBB) with the aim to prevent central nervous system cancer dissemination, eventually impacting on LM appearance and its subsequent management. Systemic chemotherapy, often combined with intrathecal chemotherapy (when possible), was one of common indications for lung cancer patients affected by LM, without driver mutations and a good performance status but currently, with the advent of innovative systemic approaches treatment solutions in this subgroup of patients are rapidly evolving. Whole brain radiation therapy (WBRT) is the conventional treatment for patients with brain metastases. Furthermore, modern radiation techniques, as stereotactic radiotherapy (SRT), improve outcomes in those cases with a limited number of lesions. However, LM represent a minority of CNS metastases and few literature data are available to drive the radiotherapy approach. Considering all relevant progress made in this setting, after a literature review, the aim of this paper is to discuss about recent developments and therapeutic options in LM management of non-oncogene addicted NSCLC.

Systemic Therapy of Lung Cancer CNS Metastases Using Molecularly Targeted Agents and Immune Checkpoint Inhibitors

Central nervous system (CNS) metastases most commonly arise from lung cancer, with the majority of patients affected during their disease course. The prognosis for patients with untreated brain metastases is poor, with surgical resection and/or radiotherapy as classic therapeutic options. However, the value of systemic therapy in the management of CNS metastases from lung cancer is growing. Novel targeted agents for the treatment of non-small cell lung cancer (NSCLC) have demonstrated activity in treating patients with CNS involvement, and are potential alternatives to radiation and surgery. These agents include anaplastic lymphoma kinase (ALK) inhibitors such as alectinib, crizotinib, ceritinib, lorlatinib, and others; epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors, including the recently developed third-generation inhibitor osimertinib, and even immune checkpoint inhibitors such as nivolumab, pembrolizumab, and atezolizumab. This review summarizes current activity of systemic agents in the management of CNS metastases from NSCLC, as well as potential mechanisms of action of these small and large molecules.

Leptomeningeal disease: current diagnostic and therapeutic strategies

Leptomeningeal disease has become increasingly prevalent as novel therapeutic interventions extend the survival of cancer patients. Although a majority of leptomeningeal spread occurs secondary to breast cancer, lung cancer, and melanoma, a wide variety of malignancies have been reported as primary sources. Symptoms on presentation are equally diverse, often involving a combination of neurological deficits with the possibility of obstructive hydrocephalus. Diagnosis is definitively made via cerebrospinal fluid cytology for malignant cells, but neuro-imaging with high quality T1-weighted magnetic resonance imaging can aid diagnosis and localization. While leptomeningeal disease is still a terminal, late-stage complication, a variety of treatment modalities, such as intrathecal chemotherapeutics and radiation therapy, have improved median survival from 4–6 weeks to 3–6 months. Positive prognosticative factors for survival include younger age, high performance scores, and controlled systemic disease. In looking to the future, diagnostics that improve early detection and chemotherapeutics tailored to the primary malignancy will likely be the most significant advances in improving survival.

Leptomeningeal Disease and the Evolving Role of Molecular Targeted Therapy and Immunotherapy

BACKGROUND

Leptomeningeal disease (LMD) is a complication that results from solid tumor metastasis. Prognosis is extremely poor. As therapeutic options for solid tumors improve, the rate of LMD continues to increase. Until recently, treatment has been limited to radiation therapy, intrathecal chemotherapy, and systemic chemotherapy, with an overall survival of 2-3 months. Targeted molecular therapy and immunotherapies are promising new options for increasing overall survival and clinical improvement; however, optimal clinical management remains unknown.

METHODS

In this review, we discuss targeted molecular therapy and immunotherapy treatment options for LMD resulting from primary lung, breast, and melanoma tumors. In addition, we summarize dosing strategies, overall survival, clinical outcomes, and novel approaches to treatment.

RESULTS

Our review indicates a deficiency in the current literature. Presently, intrathecal trastuzumab administration may be an effective option for patients with HER2-positive breast cancer. BRAF inhibitors and cytotoxic T lymphocyte-associated antigen-4 targets have shown promising results in LMD resulting from melanoma. Finally, tyrosine kinase inhibitors may increase overall survival in epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer. Pulsatile drug administration or dual therapy may be beneficial for patients who progress to LMD while being treated with EGFR targets for their primary malignancy.

CONCLUSION

Targeted molecular therapy and immunotherapy in LMD may provide favorable treatment options. Current literature is lacking in safety, efficacy, and overall response rates from the use of targeted therapy. Research is needed to draw significant conclusions about the most appropriate therapy for patients with LMD.

Targeted therapy for leptomeningeal metastases in non-small cell lung cancer - Changing treatment paradigms

Leptomeningeal metastasis is an uncommon but serious complication in patients with advanced cancers. Leptomeningeal metastasis is diagnosed in approximately 5% of the patients, most commonly among patients with cancers of breast and lung, melanoma, and gastrointestinal malignancies. Treatment goal is to improve survival and quality of the patients. Use of targeted therapies and immunotherapy has led to improved survival of patients with non-small cell lung cancer (NSCLC). In this article, we review emerging data on use of mutation-specific agents and immunotherapy in the treatment of leptomeningeal metastasis among patients with NSCLC.