Prophylactic Cranial Irradiation for Patients with Surgically Resected Small Cell Lung Cancer.

INTRODUCTION: Data on prophylactic cranial irradiation (PCI) after complete resection of SCLC are limited. The purpose of this study was to investigate the impact of PCI in this population.

METHODS: We retrospectively identified completely resected SCLC at the Shanghai Chest Hospital between January 2006 and January 2014.

RESULTS: A total of 349 patients (115 patients who received PCI [the PCI-treated cohort] and 234 patients who did not [the non-PCI-treated cohort]) were included in the study. The results demonstrated that the PCI-treated cohort had longer overall survival than the non-PCI-treated cohort among patients with pathologic stage (p-stage) II (hazard ratio [HR] = 0.54, 95% confidence interval [CI]: 0.30-0.99, p = 0.047) and p-stage III (HR = 0.54, 95% CI: 0.34-0.86, p = 0.009) disease. Among patients with p-stage III disease, there was a significantly higher risk for cerebral recurrence from the time of diagnosis in the non-PCI-treated cohort (p = 0.018). With regard to patients with p-stage I disease, neither overall survival benefit (HR = 1.61, 95% CI: 0.68-3.83, p = 0.282) nor risk for cerebral recurrence (p = 0.389) was significant between the PCI-treated and non-PCI-treated cohorts.

CONCLUSIONS: The data presented in the current study support using PCI in patients with p-stage II/III disease but not in patients with p-stage I disease. A relatively lower risk for brain metastases in p-stage I patients might explain the inferior efficacy of PCI in this population.