Trial design on prophylaxis and treatment of brain metastases: lessons learned from the EORTC Brain Metastases Strategic Meeting 2012

Brain metastases (BM) occur in a significant proportion of cancer patients and are associated with considerable morbidity and poor prognosis. The trial design in BM patients is particularly challenging, as many disease and patient variables, statistical issues, and the selection of appropriate end-points have to be taken into account. During a meeting organised on behalf of the European Organisation for Research and Treatment of Cancer (EORTC), methodological aspects of trial design in BM were discussed. This paper summarises the issues and potential trial strategies discussed during this meeting and may provide some guidance for the design of trials in BM patients.

Changes in neurocognitive functioning and quality of life in adult patients with brain tumors treated with radiotherapy

This review aims to summarize what is currently known about neurocognitive outcome and quality of life in patients with brain tumors treated with radiotherapy. Whether potential tumor-controlling benefits of radiotherapy outweigh its potential toxicity in the natural history of brain tumors is a matter of debate. This review focuses on some of the adult main brain tumors, for which the issue of neurocognitive decline has been thoroughly studied: low-grade gliomas, brain metastases, and primary central nervous system lymphomas. The aims of this review are: (1) the analysis of existing data regarding the relationship between radiotherapy and neurocognitive outcome; (2) the identification of strategies to minimize radiotherapy-related neurotoxicity by reducing the dose or the volume; (3) the evidence-based data concerning radiotherapy withdrawal; and (4) the definition of patients subgroups that could benefit from immediate radiotherapy. For high grade gliomas, the main findings from literature are summarized and some strategies to reduce the neurotoxicity of the treatment are presented. Although further prospective studies with adequate neuropsychological follow-up are needed, this article suggests that cognitive deficits in patients with brain tumor have a multifactorial genesis: radiotherapy may contribute to the neurocognitive deterioration, but the causes of this decline include the tumor itself, disease progression, other treatment modalities and comorbidities. Treatment variables, such as total and fractional dose, target volume, and irradiation technique can dramatically affect the safety of radiotherapy: optimizing radiation parameters could be an excellent approach to improve outcome and to reduce neurotoxicity. At the same time, delayed radiotherapy could be a valid option for highly selected patients.

Treatment of brain metastases: review of phase III randomized controlled trials

The optimal management of brain metastases remains controversial. Both whole brain radiotherapy (WBRT) and local treatment [surgery (S) or radiosurgery (RS)] are the cornerstones of treatment. The role of systemic therapy is also being explored. Randomized controlled trials (RCT) have tried to assess the individual and combined effects of different therapeutic strategies. (1) RCT in oligometastatic patients: WBRT alone vs. local treatment+WBRT. Combined treatment may improve both overall survival and local control in patients with a single metastasis, but it also leads to a local control benefit in patients with two to four lesions. Exclusive local treatment vs. WBRT plus local treatment. The addition of WBRT to local treatment may result in improved local control, improved freedom from new brain metastases and improved overall brain control. S+WBRT vs. RS+WBRT. There is no evidence of superiority of a combined treatment over the other one. (2) RCT addressing the point of improving WBRT outcome: differences in WBRT fractionation do not significantly alter outcome of treatments. Only a few systemic drugs may cause some significant advantages. (3) RCT that assessed neurocognitive impairment and quality of life: the baseline cognitive performance of most patients is significantly impaired. Intracranial tumor control is an essential factor in stabilizing neurocognitive function. The data on neurocognitive toxicity related to WBRT are still contradictory. Impairment of both neurocognitive function and quality of life of patients with brain metastases needs to be further addressed in RCT.

Surgical resection and whole brain radiation therapy versus whole brain radiation therapy alone for single brain metastases

BACKGROUND

The treatment of brain metastasis is generally palliative, with whole brain radiation therapy (WBRT), since the majority have uncontrollable systemic cancer. In certain circumstances, such as single brain metastases, death may be more likely from brain involvement than systemic disease. In this group, surgical resection has been proposed to relieve symptoms and prolong survival.

OBJECTIVES

To assess the clinical effectiveness of surgical resection plus WBRT versus WBRT alone in the treatment of single brain metastasis.

SEARCH STRATEGY

The Cochrane Cancer Network Specialised trials register (July 2003), Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 1 2003), MEDLINE (1966 to July 2003), EMBASE (1980 to July 2003), CANCERLIT (1980 to July 2003), BIOSIS (1985 to July 2003) and SCIENCE CITATION INDEX (1981 to July 2003) were searched. References of identified studies were hand searched, as was the Journal of Neuro-Oncology over the previous 10 years and Neuro-Oncology over the past 2 years, including all conference abstracts. Specialists in neuro-oncology were also contacted.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing surgery and WBRT with WBRT alone, in patients with single brain metastasis.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data.

MAIN RESULTS

Three RCTs were identified, with 195 patients in total. No significant difference in survival was noted hazard ratio (HR) 0.74 (95% confidence interval (CI) 0.39 to 1.40, p = 0.35), although there was a high degree of heterogeneity between trials. One trial has shown surgery and WBRT to increase the duration of functionally independent survival (FIS) HR 0.42 (95% CI 0.22 to 0.80, p < 0.008). There is a trend for surgery and WBRT to reduce the number of deaths due to neurological cause odds ratio (OR) 0.57 (95% CI 0.29 to 1.10, p = 0.09). Adverse effects were not found to be statistically more common in any group.

AUTHORS' CONCLUSIONS

Surgery and WBRT may improve FIS but not overall survival. There is a trend that it may reduce the proportion of deaths due to neurological cause. All these results were in a highly selected group of patients. Operating on metastases does not confer significantly more adverse effects.