The role of steroids in the management of brain metastases: a systematic review and evidence-based clinical practice guideline

Effect of CYP3A4 inducer dexamethasone on hepatotoxicity of lapatinib: clinical and in vitro evidence

Concomitant usage of lapatinib, a cytochrome P450 (CYP) 3A4 substrate and dexamethasone, a CYP3A4 inducer, is a pharmacokinetic drug-drug interaction. This combination may increase the formation of reactive lapatinib metabolites, which is potentially hepatotoxic. This study aims to evaluate the clinical effect of dexamethasone on incidence of hepatotoxicity and to ascertain its in vitro role using a parallel cell culture model experimental setup. Clinical effects of dexamethasone on lapatinib-induced hepatotoxicity were evaluated in a nested case-control study based on 120 patient data obtained from our records. For the in vitro experiment, metabolically competent transforming growth factor α mouse hepatocytes (TAMH) were treated with lapatinib and viabilities were compared in the presence or absence of dexamethasone. After adjusting for confounders, patients receiving the combination were 4.57 times (95% CI 1.23-16.88, p = 0.02) more likely to develop hepatotoxicity and 3.48 times (95% CI 1.24-9.80, p = 0.02) more likely to develop a clinically important change in alanine aminotransferase than compared to the other group. Treatment of TAMH cells with lapatinib and dexamethasone caused a further reduction in viability, as compared to treatment with lapatinib alone. At 5 μM lapatinib, the introduction of dexamethasone 20 μM produced a 59% decline in viability. This is the first study to document a clinically important interaction between lapatinib and dexamethasone, which associates with an increased occurrence of hepatotoxicity. The in vitro findings have provided substantiating evidence and insights on the role of dexamethasone in lapatinib-induced hepatotoxicity.

Radiotherapeutic and surgical management for newly diagnosed brain metastasis(es): An American Society for Radiation Oncology evidence-based guideline

Purpose

To systematically review the evidence for the radiotherapeutic and surgical management of patients newly diagnosed with intraparenchymal brain metastases.

Methods and Materials

Key clinical questions to be addressed in this evidence-based Guideline were identified. Fully published randomized controlled trials dealing with the management of newly diagnosed intraparenchymal brain metastases were searched systematically and reviewed. The U.S. Preventative Services Task Force levels of evidence were used to classify various options of management.

Results

The choice of management in patients with newly diagnosed single or multiple brain metastases depends on estimated prognosis and the aims of treatment (survival, local treated lesion control, distant brain control, neurocognitive preservation).

Single brain metastasis and good prognosis (expected survival 3 months or more): For a single brain metastasis larger than 3 to 4 cm and amenable to safe complete resection, whole brain radiotherapy (WBRT) and surgery (level 1) should be considered. Another alternative is surgery and radiosurgery/radiation boost to the resection cavity (level 3). For single metastasis less than 3 to 4 cm, radiosurgery alone or WBRT and radiosurgery or WBRT and surgery (all based on level 1 evidence) should be considered. Another alternative is surgery and radiosurgery or radiation boost to the resection cavity (level 3). For single brain metastasis (less than 3 to 4 cm) that is not resectable or incompletely resected, WBRT and radiosurgery, or radiosurgery alone should be considered (level 1). For nonresectable single brain metastasis (larger than 3 to 4 cm), WBRT should be considered (level 3).

Multiple brain metastases and good prognosis (expected survival 3 months or more): For selected patients with multiple brain metastases (all less than 3 to 4 cm), radiosurgery alone, WBRT and radiosurgery, or WBRT alone should be considered, based on level 1 evidence. Safe resection of a brain metastasis or metastases causing significant mass effect and postoperative WBRT may also be considered (level 3).

Patients with poor prognosis (expected survival less than 3 months): Patients with either single or multiple brain metastases with poor prognosis should be considered for palliative care with or without WBRT (level 3).

It should be recognized, however, that there are limitations in the ability of physicians to accurately predict patient survival. Prognostic systems such as recursive partitioning analysis, and diagnosis-specific graded prognostic assessment may be helpful.

Conclusions

Radiotherapeutic intervention (WBRT or radiosurgery) is associated with improved brain control. In selected patients with single brain metastasis, radiosurgery or surgery has been found to improve survival and locally treated metastasis control (compared with WBRT alone).

Evidence-based guidelines for the management of brain metastases

The objective of this article is to present a concise summary of the most recent evidence-based guidelines in the management of metastatic brain tumors developed by the American Association of Neurologic Surgeons (AANS), Congress of Neurologic Surgeons (CNS), and the AANS/CNS Joint Section on Tumors in 2010. Target populations include patients with newly diagnosed metastases as well as recurrent or progressive lesions. The roles of radiotherapy, surgical resection, and stereotactic radiosurgery along with combination therapies are reviewed. Other topics include the role of chemotherapy, anticonvulsants, steroids, and investigational therapies.

Neurologic emergencies in patients who have cancer: diagnosis and management

The nervous system can be significantly affected by cancer. Neurologic symptoms are present in 30% to 50% of oncologic patients presenting to the emergency department or in neurologic consultation at teaching hospitals. Evaluation and treatment require collaborative effort between specialties. The causes of neurologic emergencies in patients with cancer are mostly related to effects of cancer, toxicities of treatments, infections, and paraneoplastic syndromes. These complications cause significant morbidity and mortality and require prompt and accurate diagnostic and treatment measures. This article reviews the common neurologic emergencies affecting patients with cancer and discusses epidemiology, clinical presentation, diagnosis, and treatment modalities.

Current concepts and management of glioblastoma

Glioblastoma is the most common malignant primary brain tumor in adults. Its often rapid clinical course, with many medical and psychosocial challenges, requires a multidisciplinary management. Modern multimodality treatment and care improve patients' life expectancy and quality of life. This review covers major aspects of care of glioblastoma patients with a focus on the management of common symptoms and complications. We aim to provide a guide for clinicians confronted with glioblastoma patients in their everyday practice.

Novel insights into the management of brain metastases

PURPOSE OF REVIEW

This review provides available clinical evidence regarding current therapies, discusses ongoing controversies, and introduces investigational approaches in the management of brain metastases.

RECENT FINDINGS

Novel approaches to estimating prognosis of patients with brain metastases highlight the importance of tailoring treatment to each particular patient. In the setting of unfavorable prognosis, either hospice care, symptom management, or short-course whole-brain radiotherapy (WBRT) is a critical component of palliation. In the setting of favorable or intermediate prognosis, treatment options can include a slightly more prolonged course of WBRT, surgery, stereotactic radiosurgery, systemic therapy, or a combination. Selection of the appropriate treatment is influenced by the number of brain metastases, overall patient performance status and residual life expectancy, as well as an understanding of the benefits and toxicities of each modality. Recent clinical studies have shed novel insight on the temporal sequence of memory changes following WBRT. Innovative approaches to mitigating these radiation-induced memory effects are currently being investigated.

SUMMARY

Evidence-based management of brain metastases represents an evolving field of active clinical research. Ongoing and future investigations focus on the preservation of cognition and quality of life, in addition to conventional outcomes such as intracranial tumor control and survival.

Brain metastases

INTRODUCTION

Metastases to the central nervous system may occur with tumours of any primary origin. Brain (cerebral) metastases may be either single or multiple, with or without disseminated disease elsewhere. Brain metastases may present with focal or generalised symptoms, although up to one third of people may be asymptomatic.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical question: What are the effects of interventions for managing brain metastases in adults? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We identified 38 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We have performed a GRADE evaluation of the quality of evidence for interventions included in this review.

CONCLUSIONS

In this systematic review, we present information relating to the effectiveness and safety of the following interventions: corticosteroids, surgery, radiosurgery, whole-brain radiotherapy (external beam), cytotoxic chemotherapy (systemic), surgery plus radiosurgery, surgery plus whole-brain radiotherapy (external beam), whole-brain radiotherapy plus radiosurgery, surgery plus radiosurgery plus whole-brain radiotherapy (external beam), and whole-brain radiotherapy (external beam) plus radiation sensitisers.

Management of brain metastases

OPINION STATEMENT

As systemic cancer therapies have improved, the natural history and importance of treating brain metastases continues to evolve. Historically, most patients with brain metastases have been managed with whole brain radiation therapy (WBRT) with surgical resection or radiosurgery added for patients with single or few metastases. Because the potential late toxicity of WBRT is increasingly recognized when systemic tumor is more effectively controlled, there has been increased interest in the use of focal therapies such as radiosurgery with deferred WBRT even for patients with larger numbers of metastases. Although WBRT in combination with radiosurgery or surgical resection significantly reduces central nervous system recurrences at the treated site and elsewhere in the brain, it is not clear whether a patient's quality of life is more affected by tumor recurrence or by treatment with WBRT. In our practice, most patients with fewer than 7 to 10 tumors are treated with radiosurgery alone, with WBRT initially deferred because of concerns about its late toxicity. The ongoing technical improvements in radiosurgery have made this transition away from WBRT clinically feasible. This approach also allows patients to begin systemic therapy sooner, rather than waiting 2 to 4 weeks to complete WBRT. For patients with large or very symptomatic tumors, surgical resection is performed, followed by postoperative radiosurgery to the resection cavity, again initially deferring WBRT for many patients. This focal-only approach in the postoperative setting is associated with a higher rate of subdural dissemination and needs further prospective study, as some would argue that tumor progression is the major determinant of loss of function. Ultimately, better survival will require better systemic therapy that both controls extracranial disease and penetrates the brain to reduce intracranial recurrences. Unfortunately, many clinical trials of novel agents exclude patients with brain metastases.

Corticosteroids in brain cancer patients: benefits and pitfalls

Glucocorticoids have been used for decades in the treatment of brain tumor patients and belong to the most powerful class of agents in reducing tumor-associated edema and minimizing side effects and the risk of encephalopathy in patients undergoing radiation therapy. Unfortunately, corticosteroids are associated with numerous and well-characterized adverse effects, constituting a major challenge in patients requiring long-term application of corticosteroids. Novel antiangiogenic agents, such as bevacizumab (Avastin®), which have been increasingly used in cancer patients, are associated with significant steroid-sparing effects, allowing neuro-oncologists to reduce the overall use of corticosteroids in patients with progressive malignant brain tumors. Recent experimental studies have revealed novel insights into the mechanisms and effects of corticosteroids in cancer patients, including modulation of tumor biology, angiogenesis and steroid-associated neurotoxicity. This article summarizes current concepts of using corticosteroids in brain cancer patients and highlights potential pitfalls in their effects on both tumor and neural progenitor cells.