P2.05-025 9-Year Experience: Prophylactic Cranial Irradiation in Extensive Disease Small-Cell Lung Cancer: Topic: Clinical Outcome

Abstract

In 2007, a EORTC study demonstrated a beneficial impact on overall survival with the use of prophylactic cranial irradiation in extensive disease small cell lung cancer. Nevertheless, there is ongoing debate over the role of PCI as patients in this trial did not undergo imaging of the brain prior to treatment, and a recent Japanese randomized trial showed a detrimental effect of PCI on OS in patients with a negative pre-treatment brain MRI. 87% of our patients received brain imaging prior to PCI. We examined the medical records of 137 patients with extensive disease small cell lung cancer who initially responded to chemotherapy and received PCI between 2007 and 2015. The outcomes, including the development of brain metastases and OS following PCI were analyzed. Survival and correlations were calculated using log-rank, univariate, and multivariate Cox proportional hazards-ratio analyses. Median OS after PCI was 12 months and the median nPFS after PCI was 19 months. There was no significant survival difference in patients who received an MRI prior to PCI compared to patients who received a contrast enhanced computer tomography (CT) (p=0.20). Univariate analysis for overall survival did not show a statistically significant effect for known cofactors. We present the 9-year clinical experience with PCI in ED SCLC patients from one of Europe’s largest Lung Cancer Centres. PCI leads to a nearly doubled median OS compared to the irradiation arm of the EORTC trial with a 2-months prolonged median OS compared to the irradiation arm of the Japanese trial. PCI should remain standard of care for all patients with SCLC who have a response to initial chemotherapy. Contrast enhanced brain MRI instead of CT for staging prior to PCI is recommended if possible.