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Author Cherpak, Amanda ♦ Chytyk-Praznik, Krista ♦ Yewondwos
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword APPLIED LIFE SCIENCES ♦ RADIATION PROTECTION AND DOSIMETRY ♦ BIOMEDICAL RADIOGRAPHY ♦ BONE MARROW ♦ DISTANCE ♦ GY RANGE 10-100 ♦ IMAGES ♦ PLANNING ♦ RADIOTHERAPY ♦ WHOLE-BODY IRRADIATION
Abstract Purpose: TMI targets only the bone marrow, with the intent of sparing normal tissues. The NSCC has recently implemented a TMI protocol which includes VMAT fields to treat the bone marrow from head to mid-thigh and extended SSD POP fields to treat the lower legs. This work describes the commissioning and initial clinical results of the first reported VMAT TMI treatments in Canada. Methods: Detailed CT simulation, imaging, planning and treatment procedures were developed by a multi-disciplinary team. Patients have 1 cm of bolus over the lower legs and 0.5 cm of bolus around the lower arms. The PTV includes all bone, except mandible, facial bones and hands, with the objective of V(12 Gy) > 90%. Detailed analysis of the influence of field overlap was performed to determine optimal field placement and image-guidance tolerances. Results: PTV coverage was achieved for all cases as V(12 Gy) ranged from 90.4–96.3%. The minimum dose to the PTV, D(99%), ranged from 91.4–97.87% and V(90%Rx=10.8 Gy) ranged from 99.1–100.0%. The lungs, liver and heart had an average D{sub mean} of (7.8±0.3)Gy/(65±2)%, (7.6±0.7)Gy/(63±5)%, and (6.8±0.4)Gy/(56±4)% respectively. Conclusions: Commissioning required input and collaboration from all team members. Transitioning from TBI to TMI requires additional time for contouring, treatment planning, QA, and treatment. Patient benefit can however be seen in the quality of OAR sparing.
ISSN 00942405
Educational Use Research
Learning Resource Type Article
Publisher Date 2016-08-15
Publisher Place United States
Journal Medical Physics
Volume Number 43
Issue Number 8


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