Prophylactic cranial irradiation for stage IV small cell lung cancer, live longer or reduce morbidity of brain metastases?

Current approaches to the management of brain metastases

Brain metastases are a very common manifestation of cancer that have historically been approached as a single disease entity given the uniform association with poor clinical outcomes. Fortunately, our understanding of the biology and molecular underpinnings of brain metastases has greatly improved, resulting in more sophisticated prognostic models and multiple patient-related and disease-specific treatment paradigms. In addition, the therapeutic armamentarium has expanded from whole-brain radiotherapy and surgery to include stereotactic radiosurgery, targeted therapies and immunotherapies, which are often used sequentially or in combination. Advances in neuroimaging have provided additional opportunities to accurately screen for intracranial disease at initial cancer diagnosis, target intracranial lesions with precision during treatment and help differentiate the effects of treatment from disease progression by incorporating functional imaging. Given the numerous available treatment options for patients with brain metastases, a multidisciplinary approach is strongly recommended to personalize the treatment of each patient in an effort to improve the therapeutic ratio. Given the ongoing controversies regarding the optimal sequencing of the available and expanding treatment options for patients with brain metastases, enrolment in clinical trials is essential to advance our understanding of this complex and common disease. In this Review, we describe the key features of diagnosis, risk stratification and modern paradigms in the treatment and management of patients with brain metastases and provide speculation on future research directions.

The Role of Prophylactic Cranial Irradiation in Patients With Extensive Stage Small Cell Lung Cancer: A Systematic Review and Meta-Analysis

INTRODUCTION

The role of prophylactic cranial irradiation (PCI) is controversial in patients with extensive stage small cell lung cancer. The aim of this study was to determine the impact of PCI in these patients.

METHODS

We performed a systematic review and meta-analysis in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. A systematic literature search was conducted in MEDLINE, EMBASE, and the Cochrane Central Register. The primary outcome was overall survival (OS).

RESULTS

We identified five studies comprising 984 patients, of whom 448 received PCI and 536 did not receive PCI. In pooled estimates, PCI did not statistically improve OS compared with controls (hazard ratio [HR] = 0.82; 95% confidence interval [CI]: 0.60-1.11; I² = 77%; p = 0.19). However, the PCI group had a significant advantage in 1-year survival compared to the no-PCI group (37.1% versus 27.1%; risk ratio = 0.87; 95% CI: 0.80-0.95; I² = 47%; p = 0.002), and the pooled estimates indicated that progression-free survival and the risk of brain metastasis were associated with significant benefit in the PCI group (HR = 0.83; 95% CI: 0.70-0.98; I² = 22%; p = 0.03; and HR = 0.34; 95% CI: 0.23-0.50; I² = 0%; p < 0.001, respectively).

CONCLUSIONS

Our findings suggest that PCI in patients with extensive stage small cell lung cancer may lead to a significant benefit in 1-year survival, progression-free survival, and the risk of brain metastasis, despite the lack of a significant advantage in OS.