National Cancer Center/National Clinical Research Center for Cancer Cancer Hospital, CAMS & PUMC Beijing, Beijing
T. Zhan1, L. Deng1, N. Bi1, W. Wang1, T. Zhang1, J. Wang2, X. Wang1, W. Liu Jr1, Y. Zhai3, Z. Xiao3, J. LV1, F. Qinfu1, Y. X. Li3, and Z. Zhou3; 1Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences (CAMS) and Peking Union Medical College (PUMC), Beijing, China, 2Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China, 3Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
Purpose/Objective(s): To analysis the treatment efficacy, safety and dose parameters of optimized hippo-avoidance prophylactic cranial irradiation (OHA-PCI) in limited-stage small cell lung cancer (LS-SCLC). Materials/
Methods: This cohort study reviewed patients with LS-SCLC receiving prophylactic cranial irradiation under optimized hippo-avoidance technique (hippocampus avoidance region defined as hippocampus region plus 2mm in three dimension) from August 2014 to June 2020 in National Cancer Center of China. Dose parameters of OHA-PCI, adverse events, neurocognitive function (HVLT-R) were analyzed using descriptive statistics analysis. OS and PFS were calculated using Kaplan-Meier method. The cumulative incidence of local-regional recurrence (LRR), brain metastases (BM), and extracranial distant metastases (EDM) were investigated under competing risk analysis. Results: A total of 112 patients were included, the median follow-up was 50 months (95%CI: 45.61-54.38). The median volume of hippo was 4.85 ml (Range: 2.65-8.34 ml), with the average dose lower than 9Gy in 106 patients (94.6%), 8Gy in 92 patients (82.1%). The median volume of hippo avoidance area was 15.00 ml (Range: 8.61-28.06 ml), with the average dose lower than 12Gy in 109 patients (97.3%), 10Gy in 101 patients (90.2%). The five-year cumulative intracranial recurrence, extracranial distant metastases, locoregional recurrence were 23.2%, 26.9%, 33.3%, respectively. The median progression-free survival was 34 months (95%CI: 18-NA). The most common I-II grade adverse events were nausea (33.9%) and dizziness (31.3%), with only one patient underwent III grade nausea. The decline of neurocognitive function test remained a low level in assessable patients. Conclusion: Optimized HA-PCI could achieve similar dose limitation with favorable efficacy and minor toxicity.
