Prophylactic Cranial Irradiation in Extensive Stage Small Cell Lung Cancer: Outcomes at a Comprehensive Cancer Centre

Area of Science:

• Oncology
• Radiotherapy
• Medical Imaging

Background:

• The role of prophylactic cranial irradiation (PCI) in extensive stage small cell lung cancer (ES-SCLC) is debated due to conflicting trial results.
• Discrepancies in post-chemotherapy brain imaging protocols between trials complicate interpretation.

Purpose of the Study:

• To evaluate the impact of PCI on survival and brain metastasis development in ES-SCLC.
• To address the influence of varying post-chemotherapy brain imaging practices on study outcomes.

Main Methods:

• Retrospective review of 155 eligible ES-SCLC patients treated between 2005-2011.
• Kaplan-Meier analysis compared overall survival and time to brain metastasis in patients who received PCI versus those who did not.
• Patients were stratified based on initial post-chemotherapy brain imaging; multivariate analysis identified predictors of survival.

Main Results:

• PCI was a significant predictor of improved overall survival (HR 0.55; P=.0005) and reduced brain metastasis (HR 0.40; P=.0004).
• Median survival was 13.5 months with PCI versus 8.5 months without PCI.
• Survival benefit with PCI was evident in both groups that received (HR 0.55; P=.012) and did not receive (HR 0.48; P=.0025) initial post-chemotherapy imaging.

Conclusions:

• PCI offers a survival benefit and delays brain metastasis in ES-SCLC patients achieving at least a partial response to chemotherapy.
• The findings support PCI use, considering initial imaging but not routine surveillance, for eligible ES-SCLC patients.