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Author Kok, H. Petra ♦ Korshuize- van Straten, Linda ♦ Bakker, Akke ♦ Kroon- Oldenhof, Rianne de ♦ Geijsen, Elisabeth D. ♦ Stalpers, Lukas J. A. ♦ Crezee, Johannes
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword RADIOLOGY AND NUCLEAR MEDICINE ♦ HEATING ♦ HOT SPOTS ♦ HYPERTHERMIA ♦ NEOPLASMS ♦ PATIENTS
Abstract Background: Adequate tumor temperatures during hyperthermia are essential for good clinical response, but excessive heating of normal tissue should be avoided. This makes locoregional heating using phased array systems technically challenging. Online application of hyperthermia treatment planning could help to improve the heating quality. The aim of this study was to evaluate the clinical benefit of online treatment planning during treatment of pelvic tumors heated with the AMC-8 locoregional hyperthermia system. Methods: For online adaptive hyperthermia treatment planning, a graphical user interface was developed. Electric fields were calculated in a preprocessing step using our in-house–developed finite-difference–based treatment planning system. This allows instant calculation of the temperature distribution for user-selected phase-amplitude settings during treatment and projection onto the patient's computed tomographic scan for online visualization. Online treatment planning was used for 14 treatment sessions in 8 patients to reduce the patients' reports of hot spots while maintaining the same level of tumor heating. The predicted decrease in hot spot temperature should be at least 0.5°C, and the tumor temperature should decrease less than 0.2°C. These predictions were compared with clinical data: patient feedback about the hot spot and temperature measurements in the tumor region. Results: In total, 17 hot spot reports occurred during the 14 sessions, and the alternative settings predicted the hot spot temperature to decrease by at least 0.5°C, which was confirmed by the disappearance of all 17 hot spot reports. At the same time, the average tumor temperature was predicted to change on average −0.01°C (range, −0.19°C to 0.34°C). The measured tumor temperature change was on average only −0.02°C (range, −0.26°C to 0.31°C). In only 2 cases the temperature decrease was slightly larger than 0.2°C, but at most it was 0.26°C. Conclusions: Online application of hyperthermia treatment planning is reliable and very useful to reduce hot spots without affecting tumor temperatures.
ISSN 03603016
Educational Use Research
Learning Resource Type Article
Publisher Date 2017-11-15
Publisher Place United States
Journal International Journal of Radiation Oncology, Biology and Physics
Volume Number 99
Issue Number 4


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