TY - JOUR
T1 - Monte Carlo characterization of target doses in stereotactic body radiation therapy (SBRT)
AU - Rassiah-Szegedi, Premavathy
AU - Salter, Bill J.
AU - Fuller, Clifton D.
AU - Blough, Melissa
AU - Papanikolaou, Niko
AU - Fuss, Martin
N1 - Copyright:
Copyright 2011 Elsevier B.V., All rights reserved.
PY - 2006/9/1
Y1 - 2006/9/1
N2 - To compare finite-size pencil beam/equivalent path-length (FSPB/EPL) and Monte Carlo (MC) SBRT dose computations for serial tomotherapy and to quantitatively assess dose differences between the dose calculation methods. Based on 72 SBRT plans for pulmonary targets, FSPB/EPL, considering the inhomogeneous lung environment, and MC calculations were performed to establish differences between FSPB/EPL predicted dose and MC derived doses. Compared with MC, FSPB/EPL consistently overestimated minimum doses to the clinical target volume and planning target volumes by an average of 18.1±7.15% (range 4 to 33.4%), and 21.9±10.4% (range 1.2 to 45.5%), respectively. The respective mean target dose differences were 15.5±7.4% (2.8-36.4%) and 19.2±7.6% (3.6-40.1%). Deviations from MC doses were lesion size and location dependent, with smaller lesions completely embedded into lung parenchyma being most susceptible. Larger lesion in contact with mediastinum and chest wall showed lesser differences. In comparison with MC dose calculation, FSPB/EPL overestimates doses delivered to pulmonary SBRT targets. The observed dose differences may have impact on local tumor control rates, and may deserve consideration when using fast, but less accurate dose calculation methods.
AB - To compare finite-size pencil beam/equivalent path-length (FSPB/EPL) and Monte Carlo (MC) SBRT dose computations for serial tomotherapy and to quantitatively assess dose differences between the dose calculation methods. Based on 72 SBRT plans for pulmonary targets, FSPB/EPL, considering the inhomogeneous lung environment, and MC calculations were performed to establish differences between FSPB/EPL predicted dose and MC derived doses. Compared with MC, FSPB/EPL consistently overestimated minimum doses to the clinical target volume and planning target volumes by an average of 18.1±7.15% (range 4 to 33.4%), and 21.9±10.4% (range 1.2 to 45.5%), respectively. The respective mean target dose differences were 15.5±7.4% (2.8-36.4%) and 19.2±7.6% (3.6-40.1%). Deviations from MC doses were lesion size and location dependent, with smaller lesions completely embedded into lung parenchyma being most susceptible. Larger lesion in contact with mediastinum and chest wall showed lesser differences. In comparison with MC dose calculation, FSPB/EPL overestimates doses delivered to pulmonary SBRT targets. The observed dose differences may have impact on local tumor control rates, and may deserve consideration when using fast, but less accurate dose calculation methods.
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U2 - 10.1080/02841860600919225
DO - 10.1080/02841860600919225
M3 - Article
C2 - 16982568
AN - SCOPUS:33748869892
SN - 0284-186X
VL - 45
SP - 989
EP - 994
JO - Acta Oncologica
JF - Acta Oncologica
IS - 7
ER -