Prophylactic brain irradiation: still an open question (review)

Area of Science:

• Oncology
• Radiation Oncology
• Clinical Trials

Background:

• Prophylactic cranial irradiation (PCI) remains controversial despite numerous randomized trials.
• Existing evidence suggests PCI reduces brain recurrences but lacks a significant impact on overall survival.
• Heterogeneity in trial designs, patient selection, and systemic treatments complicates definitive conclusions.

Purpose of the Study:

• To evaluate the efficacy of prophylactic cranial irradiation (PCI) in preventing brain metastases.
• To assess the impact of PCI on overall survival, disease-free survival, and central nervous system (CNS) recurrence rates.
• To analyze the potential benefits against the risks of late CNS toxicity associated with PCI.

Main Methods:

• Review and meta-analysis of ten published randomized trials on prophylactic cranial irradiation.
• Analysis of patient selection criteria, irradiation schedules, and concurrent systemic treatments across studies.
• Evaluation of overall survival, disease-free survival, and incidence of brain recurrences as primary endpoints.

Main Results:

• Most trials indicate PCI effectively reduces the rate of brain recurrences.
• No significant improvement in overall survival has been consistently demonstrated across major trials.
• Some studies report potential positive impacts on survival, though these are often from single institutions.

Conclusions:

• PCI demonstrates a clear benefit in reducing central nervous system (CNS) relapses.
• The benefit of reduced CNS relapses is significant given the poor quality of life associated with brain metastases.
• Late CNS toxicity in patients receiving PCI may offset potential clinical advantages, warranting careful consideration.