Rthp-29. Development of a Novel Prognostic Scoring System for Patients Receiving Re-irradiation for Recurrent High Grade Glioma
Year: 2017
Type: conference-abstract
Abstract: Despite mounting evidence for the use of re-irradiation (re-RT) in recurrent high grade glioma, optimal patient selection criteria for re-RT remain unknown. We present a novel scoring system based on radiobiology principles including target independent factors, the likelihood of target control, and the anticipated organ at risk (OAR) toxicity for proper patient selection for re-RT of recurrent glioma. 31 patients with recurrent glioma who received re-RT (2008-2016) at NCI–NIH were included in the analysis. A novel scoring system was designed to include: 1) independent factors (age, KPS, histology, presence of symptoms), 2) target control tumor size, recurrence location, diffuse disease), and 3) OAR toxicity risk (OAR location, previous OAR dose, disease-free interval). Kaplan-Meier analysis was performed for overall survival (OS) and progression free survival (PFS) for comparison amongst variables. 31 patients, median age 46 (18 -73), with original diagnosis of (18 GBM, 5 anaplastic astrocytoma, 8 other) were analysed. Mean recurrence GTV and PTV were 29 cm3 (0.3-313) and 124 cm3 (0.5–511), respectively. Mean initial RT dose was 60 Gy (18-60) with a disease-free interval of 4.28 years (0.95-14.51). Re-RT dose was 30 Gy (15-54). Median PFS and OS from re-RT were 4 months (0.5-103) and 6 months (0.7-103), respectively. The independent factor and target control scores were each statistically significant for OS and in combination for both OS (p=0.02) and PFS (p=0.006). The anticipated toxicity risk score was not statistically significant. Our scoring system, which utilizes a radiobiological rationale in terms of target control, OAR toxicity risk, and patient factors, represents a novel in-depth approach to patient selection for re-RT in recurrent high grade glioma. Further validation in larger patient cohorts including compilation of doses to tumor and OAR may help refine this further for inclusion into clinical trials and practice surrounding re-RT.
Source: Neuro-Oncology
Institutions: National Institutes of Health, National Cancer Institute
Language: English
Subfield: Genetics
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2767575788