TY - JOUR
T1 - A dosimetric comparison of stereotactic body radiation therapy techniques for lung cancer
T2 - Robotic versus conventional linac-based systems
AU - Ding, Chuxiong
AU - Chang, Cheng Hui
AU - Haslam, Joshua
AU - Timmerman, Robert
AU - Solberg, Timothy
PY - 2010
Y1 - 2010
N2 - The aim of this study is to compare the dosimetric characteristics of robotic and conventional linac-based SBRT techniques for lung cancer, and to provide planning guidance for each modality. Eight patients who received linac-based SBRT were retrospectively included in this study. A dose of 60 Gy given in three fractions was prescribed to each target. The Synchrony Respiratory Tracking System and a 4D dose calculation methodology were used for CyberKnife and linac-based SBRT, respectively, to minimize respiratory impact on dose calculation. Identical image and contour sets were used for both modalities. While both modalities can provide satisfactory target dose coverage, the dose to GTV was more heterogeneous for CyberKnife than for linac planning/delivery in all cases. The dose to 1000 cc lung was well below institutional constraints for both modalities. In the high dose region, the lung dose depended on tumor size, and was similar between both modalities. In the low dose region, however, the quality of CyberKnife plans was dependent on tumor location. With anteriorly-located tumors, the CyberKnife may deliver less dose to normal lung than linac techniques. Conversely, for posteriorly-located tumors, CyberKnife delivery may result in higher doses to normal lung. In all cases studied, more monitor units were required for CyberKnife delivery for given prescription. Both conventional linacs and CyberKnife provide acceptable target dose coverage while sparing normal tissues. The results of this study provide a general guideline for patient and treatment modality selection based on dosimetric, tumor and normal tissue sparing considerations.
AB - The aim of this study is to compare the dosimetric characteristics of robotic and conventional linac-based SBRT techniques for lung cancer, and to provide planning guidance for each modality. Eight patients who received linac-based SBRT were retrospectively included in this study. A dose of 60 Gy given in three fractions was prescribed to each target. The Synchrony Respiratory Tracking System and a 4D dose calculation methodology were used for CyberKnife and linac-based SBRT, respectively, to minimize respiratory impact on dose calculation. Identical image and contour sets were used for both modalities. While both modalities can provide satisfactory target dose coverage, the dose to GTV was more heterogeneous for CyberKnife than for linac planning/delivery in all cases. The dose to 1000 cc lung was well below institutional constraints for both modalities. In the high dose region, the lung dose depended on tumor size, and was similar between both modalities. In the low dose region, however, the quality of CyberKnife plans was dependent on tumor location. With anteriorly-located tumors, the CyberKnife may deliver less dose to normal lung than linac techniques. Conversely, for posteriorly-located tumors, CyberKnife delivery may result in higher doses to normal lung. In all cases studied, more monitor units were required for CyberKnife delivery for given prescription. Both conventional linacs and CyberKnife provide acceptable target dose coverage while sparing normal tissues. The results of this study provide a general guideline for patient and treatment modality selection based on dosimetric, tumor and normal tissue sparing considerations.
KW - 4D CT
KW - CyberKnife
KW - Stereotactic body radiation therapy (SBRT)
KW - Synchrony respiratory tracking system
UR - http://www.scopus.com/inward/record.url?scp=77956995888&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77956995888&partnerID=8YFLogxK
U2 - 10.1120/jacmp.v11i3.3223
DO - 10.1120/jacmp.v11i3.3223
M3 - Article
C2 - 20717090
AN - SCOPUS:77956995888
SN - 1526-9914
VL - 11
SP - 212
EP - 224
JO - Journal of applied clinical medical physics
JF - Journal of applied clinical medical physics
IS - 3
ER -