Oral Targeted Therapies and Central Nervous System (CNS) Metastases

Upfront and Repeated Stereotactic Radiosurgery in Patients With Brain Metastases From NSCLC

INTRODUCTION

Approximately 40% of non-small-cell lung cancer (NSCLC) patients develop brain metastases (BM). Stereotactic radiosurgery (SRS) instead of whole-brain radiotherapy (WBRT) is increasingly administered as an upfront treatment to patients with a limited number of BM. We present outcomes and validation of prognostic scores for these patients treated with upfront SRS.

METHODS

We retrospectively analyzed 199 patients with a total of 268 SRS courses for 539 brain metastases. Median patient age was 63 years. For larger BM, dose reduction to 18 Gy or hypofractionated SRS in 6 fractions was applied. We analyzed the BMV-, the RPA-, the GPA- and the lung-mol GPA score. Cox proportional hazards models with univariate and multivariate analyses were fitted for overall survival (OS) and intracranial progression-free survival (icPFS).

RESULTS

Sixty-four patients died, 7 of them of neurological causes. Thirty eight patients (19,3%) required a salvage WBRT. Median OS was 38, 8 months (IQR: 6-NA). In univariate analysis as well as multivariate analysis, the Karnofsky performance scale index (KPI) ≥90% (P = 0, 012 and P = 0, 041) remained as independent prognostic factor for longer OS. All 4 prognostic scoring indices could be validated for OS assessment (BMV P = 0, 007; RPA P = 0, 026; GPA P = 0, 003; lung-mol GPA P = 0, 05).

CONCLUSION

In this large cohort of NSCLC patients with BM treated with upfront and repeated SRS, OS was markedly favourable, in comparison to literature. Upfront SRS is an effective treatment approach in those patients and can decidedly reduce the impact of BM on overall prognosis. Furthermore, the analysed scores are useful prognostic tools for OS prediction.

Chemotherapy for the Management of Cerebral Metastases

Chemotherapy has played a minor role as adjuvant therapy in treatment of cerebral metastases from solid cancers. The blood-brain barrier and cerebral metastases' considerable machinery of self-preservation have been significant obstacles to delivery and efficacy of chemotherapy. However, several methods intended to surmount these challenges have arisen alongside advent of technology and with the development of targeted molecular therapies. Focused ultrasound and molecular Trojan horses represent two such novel means of increasing permeability of the blood-brain barrier to effector agents. Published data on efficacy of these targeted therapies remain mostly restricted to retrospective studies and phase II prospective clinical trials.

Prophylactic Cranial Irradiation in Patients With Non-Small-Cell Lung Cancer: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

We systematically reviewed the literature for trials addressing the efficacy of prophylactic cranial irradiation (PCI) in patients with non-small-cell lung cancer (NSCLC) treated with a curative intent.

METHODS

Randomized controlled trials (RCT) comparing PCI to no PCI in patients with NSCLC treated with a curative intent were eligible for inclusion. We searched EMBASE, MEDLINE, PubMed, and CENTRAL between 1946 and July 2016. We also received continual search alerts from PubMed through September 2017. Search terms included "non-small-cell lung carcinoma," "cranial irradiation," and "randomized controlled trials." We conducted meta-analyses using random-effects models for relative measures of treatment effect for the incidence of brain metastasis, overall survival (OS), and disease-free survival (DFS). We used Parmar's methodology to derive hazard ratios (HR) when not explicitly stated in RCTs. We narratively synthesized data for the impact of PCI on quality of life (QoL) and neurocognitive function (NCF). We assessed the quality of evidence using the Grading of Recommendations, Assessment, Development, and Evaluation methodology.

RESULTS

Out of 3,548 citations captured by the search strategy, we retained 8 papers and 1 abstract, reporting on 6 eligible trials. Patients who received PCI had a significant reduction in the risk of developing brain metastases as compared with patients who did not [relative risk (RR) = 0.37; 95% confidence interval (CI): 0.26-0.52; moderate quality evidence]. However, there was no OS benefit (HR = 1.08, 95% CI: 0.90-1.31; moderate quality evidence). Sensitivity analysis excluding older studies did not show substantively different findings. DFS was reported in the two most recent trials that included only stage III patients. There was significant improvement in DFS with PCI (HR = 0.67; 95% CI: 0.46-0.98; high quality evidence). Two studies that reported on QoL reported no statistically significant differences. There was no significant difference in NCF decline in the only study that reported on this outcome, except in immediate and delayed recall, as assessed by the Hopkins Verbal Learning Test.

CONCLUSION

There is moderate quality evidence that the use of PCI in patients with NSCLC decreases the risk of brain metastases, but does not provide an OS benefit. However, data limited to stage III patients suggests that PCI improves DFS, with no effect on QoL.