Radiation sparing of cerebral cortex in brain tumor patients using quantitative neuroimaging. Issue 1 (January 2016)

• Record Type: Journal Article
• Authors: Karunamuni, Roshan A.; Moore, Kevin L.; Seibert, Tyler M.; Li, Nan; White, Nathan S.; Bartsch, Hauke; Carmona, Ruben; Marshall, Deborah; McDonald, Carrie R.; Farid, Nikdokht; Krishnan, Anithapriya; Kuperman, Joshua; Mell, Loren K.; Brewer, James; Dale, Anders M.; Moiseenko, Vitali; Hattangadi-Gluth, Jona A.
• Is Part Of: Radiotherapy and oncology. Volume 118:Issue 1(2016:Jan.)
• Page Start: 29
• Page End: 34
• Publication Date: 2016-01
• Subjects: Cortex -- Glioma -- Radiation sparing -- OAR; Oncology -- Periodicals; Radiotherapy -- Periodicals; Tumors -- Periodicals; Medical Oncology -- Periodicals; Neoplasms -- radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiothérapie -- Périodiques; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Electronic journals; 616.9940642
• DOI: 10.1016/j.radonc.2016.01.003
• Languages: English
• ISSNs: 0167-8140

Abstract

Abstract: Background and purpose: Neurocognitive decline in brain tumor patients treated with radiotherapy (RT) may be linked to cortical atrophy. We developed models to determine radiation treatment-planning objectives for cortex, which were tested on a sample population to identify the dosimetric cost of cortical sparing. Material and methods: The relationship between the probability of cortical atrophy in fifteen high-grade glioma patients at 1-year post-RT and radiation dose was fit using logistic mixed effects modeling. Cortical sparing was implemented using two strategies: region-specific sparing using model parameters, and non-specific sparing of all normal brain tissue. Results: A dose threshold of 28.6 Gy was found to result in a 20% probability of severe atrophy. Average cortical sparing at 30 Gy was greater for region-specific dose avoidance (4.6%) compared to non-specific (3.6%). Cortical sparing resulted in an increase in heterogeneity index of the planning target volume (PTV) with an average increase of 1.9% (region-specific) and 0.9% (non-specific). Conclusions: We found RT doses above 28.6 Gy resulted in a greater than 20% probability of cortical atrophy. Cortical sparing can be achieved using region-specific or non-specific dose avoidance strategies at the cost of an increase in the dose heterogeneity of the PTV.