The Use of Prophylactic Cranial Irradiation (PCI) and Consolidative Thoracic Radiation (TRT) in Extensive Stage Small Cell Lung Cancer (ES-SCLC) in the United States (US) and its Survival Benefit

Abstract

The role of PCI and TRT in ES-SCLC remains controversial. While the European study showed benefit of PCI in this disease, a Japanese study showed no such survival improvement. Similarly, addition of TRT also has conflicting results making it difficult to adopt in common practice. We aimed to review the practice pattern of using PCI and TRT in the US and whether it improves overall survival following initial chemotherapy. We analyzed National cancer database to identify patients with stage IV (ES-SCLC) disease diagnosed between 2004-2014. Patients with brain metastasis at diagnosis and who died within 30 days from diagnosis were excluded. 19% (n=5988) who did not receive any chemotherapy, 2% (n=721) who had single agent chemotherapy were excluded. 73% (n=23,458) patients received multiagent chemotherapy and were included (n=23,458; 73%) in this analysis. Statistical significance was defined as p≤.05 using statistical software. The median age was 67 years (21-90 years) with median follow up of 9 months (2-70 months). 50% patients were male. Majority of patients (n=14,439, 87%)) did not receive any radiation, 13% (n=2217) received PCI and 19% (n=4363) received TRT, while 9% (n=2130) patients received other palliative radiation. Addition of PCI and TRT improved median survival, 1 year and two years survival significantly (Table 1).Tabled 1Abstract TU_38_3701; Table 1 Survival difference with and without PCI and TRTSurvivalPCINo PCITRTNo TRTp-valueMedian survival (months)12.758.5111.438.51<.0011-year OS52.59%26.74%44.83%26.74%<.0012-year OS13.12%6.0%15.56%6%<.001 Open table in a new tab This hospital-based registry analysis shows that PCI and TRT are not commonly utilized for ES-SCLC in patients who otherwise were treated with multiagent chemotherapy. However, this study shows significant OS benefit with addition of PCI and TRT in this otherwise poor prognostic group. Further research is needed to confirm the role of PCI and TRT especially in the era of improved systemic therapy.