TY - JOUR
T1 - Analysis of cardiac substructure dose in a large, multi-centre danish breast cancer cohort (the DBCG HYPO trial)
T2 - Trends and predictive modelling
AU - Finnegan, Robert
AU - Lorenzen, Ebbe Laugaard
AU - Dowling, Jason
AU - Jensen, Ingelise
AU - Berg, Martin
AU - Thomsen, Mette Skovhus
AU - Delaney, Geoff P.
AU - Koh, Eng Siew
AU - Thwaites, David
AU - Brink, Carsten
AU - Offersen, Birgitte Vrou
AU - Holloway, Lois
N1 - Funding Information:
The DBCG HYPO trial was supported by the Danish Cancer Society and CIRRO (Center for Interventional Research in Radiation Oncology). This work was made possible by support from an Endeavour Fellowship (Australian Government; Department of Education, Skills and Employment) and further support from a South West Sydney Local Health District Radiation Oncology Medical Physics scholarship.
Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2020/12
Y1 - 2020/12
N2 - Background and purpose: Radiotherapy for breast cancer can increase the risks of heart disease. Patient-specific risk assessment may be improved with the inclusion of doses to cardiac substructures. The purpose of this work was to use automatic segmentation to evaluate substructure doses and develop predictive models for these based on the dose to the whole heart. Material and methods: Automatic segmentation was used to delineate cardiac substructures in a Danish breast cancer trial (DBCG HYPO) dataset comprising over 1500 Danish women treated between 2009 and 2014. Trends in contouring practices and cardiac doses over time were investigated, and models to predict substructure doses from whole heart dose parameters were fit to the data. Results: Manual contouring consistency improved over the study period when compared with automatic segmentation; systematic differences between automatically and manually defined heart volume decreased from 106 cm3 to 12.0 cm3. Doses to the heart and cardiac substructures also decreased. Mean whole heart doses for left-sided treatments in 2009 and 2014 were 1.94±1.19 Gy and 1.29±0.69 Gy (average ± SD), respectively. Prediction of mean substructure doses is accurate, with R2 scores in the range 0.45–0.95 (average 0.77), depending on the particular structure. Conclusion: This study reports heart and cardiac substructure doses in a large breast cancer cohort. Predictive models generated in this work can be used to estimate mean cardiac substructure doses for datasets where patient imaging and dose distributions are not available, provided the tangential field techniques are consistent with those used in the trial.
AB - Background and purpose: Radiotherapy for breast cancer can increase the risks of heart disease. Patient-specific risk assessment may be improved with the inclusion of doses to cardiac substructures. The purpose of this work was to use automatic segmentation to evaluate substructure doses and develop predictive models for these based on the dose to the whole heart. Material and methods: Automatic segmentation was used to delineate cardiac substructures in a Danish breast cancer trial (DBCG HYPO) dataset comprising over 1500 Danish women treated between 2009 and 2014. Trends in contouring practices and cardiac doses over time were investigated, and models to predict substructure doses from whole heart dose parameters were fit to the data. Results: Manual contouring consistency improved over the study period when compared with automatic segmentation; systematic differences between automatically and manually defined heart volume decreased from 106 cm3 to 12.0 cm3. Doses to the heart and cardiac substructures also decreased. Mean whole heart doses for left-sided treatments in 2009 and 2014 were 1.94±1.19 Gy and 1.29±0.69 Gy (average ± SD), respectively. Prediction of mean substructure doses is accurate, with R2 scores in the range 0.45–0.95 (average 0.77), depending on the particular structure. Conclusion: This study reports heart and cardiac substructure doses in a large breast cancer cohort. Predictive models generated in this work can be used to estimate mean cardiac substructure doses for datasets where patient imaging and dose distributions are not available, provided the tangential field techniques are consistent with those used in the trial.
KW - Automatic segmentation
KW - Breast cancer radiotherapy
KW - Cardiac substructures
UR - http://www.scopus.com/inward/record.url?scp=85094877655&partnerID=8YFLogxK
U2 - 10.1016/j.radonc.2020.09.004
DO - 10.1016/j.radonc.2020.09.004
M3 - Article
C2 - 32916238
AN - SCOPUS:85094877655
SN - 0167-8140
VL - 153
SP - 130
EP - 138
JO - Radiotherapy and Oncology
JF - Radiotherapy and Oncology
ER -