PMID- 28993138 OWN - NLM STAT- MEDLINE DCOM- 20180919 LR - 20180919 IS - 1879-8519 (Electronic) IS - 1879-8500 (Linking) VI - 8 IP - 3 DP - 2018 May-Jun TI - The impact of imaging modality (CT vs MRI) and patient position (supine vs prone) on tangential whole breast radiation therapy planning. PG - e87-e97 LID - S1879-8500(17)30202-3 [pii] LID - 10.1016/j.prro.2017.07.007 [doi] AB - PURPOSE: The purpose of this study was to evaluate the impact of magnetic resonance imaging (MRI) versus computed tomography (CT)-derived planning target volumes (PTVs), in both supine and prone positions, for whole breast (WB) radiation therapy. METHODS AND MATERIALS: Four WB radiation therapy plans were generated for 28 patients in which PTVs were generated based on CT or MRI data alone in both supine and prone positions. A 6-MV tangential intensity modulated radiation therapy technique was used, with plans designated as ideal, acceptable, or noncompliant. Dose metrics for PTVs and organs at risk were compared to analyze any differences based on imaging modality (CT vs MRI) or patient position (supine vs prone). RESULTS: With respect to imaging modality 2/11 whole breast planning target volume (WB_PTV) dose metrics (percentage of PTV receiving 90% and 110% of prescribed dose) displayed statistically significant differences; however, these differences did not alter the average plan compliance rank. With respect to patient positioning, the odds of having an ideal plan versus a noncompliant plan were higher for the supine position compared with the prone position (P = .026). The minimum distance between the seroma cavity planning target volume (SC_PTV) and the chest wall was increased with prone positioning (P < .001, supine and prone values 1.1 mm and 8.7 mm, respectively). Heart volume was greater in the supine position (P = .005). Heart doses were lower in the supine position than prone (P < .01, mean doses 3.4 +/- 1.55 Gy vs 4.4 +/- 1.13 Gy for supine vs prone, respectively). Mean lung doses met ideal dose constraints in both positions, but were best spared in the prone position. The contralateral breast maximum dose to 1cc (D1cc) showed significantly lower doses in the supine position (P < .001, 4.64 Gy vs 9.51 Gy). CONCLUSIONS: Planning with PTVs generated from MRI data showed no clinically significant differences from planning with PTVs generated from CT with respect to PTV and doses to organs at risk. Prone positioning within this study reduced mean lung dose and whole heart volumes but increased mean heart and contralateral breast doses compared with supine. CI - Copyright (c) 2017 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved. FAU - Dundas, Kylie AU - Dundas K AD - Centre for Medical Radiation Physics, Faculty of Engineering and Information Sciences, University of Wollongong, Wollongong, NSW, Australia; Liverpool and Macarthur Cancer Therapy Centres, Liverpool, NSW, Australia; Ingham Institute for Applied Medical Research, Liverpool Hospital, Sydney, NSW, Australia. Electronic address: Kylie.Dundas@swsahs.nsw.gov.au. FAU - Pogson, Elise M AU - Pogson EM AD - Centre for Medical Radiation Physics, Faculty of Engineering and Information Sciences, University of Wollongong, Wollongong, NSW, Australia; Liverpool and Macarthur Cancer Therapy Centres, Liverpool, NSW, Australia; Ingham Institute for Applied Medical Research, Liverpool Hospital, Sydney, NSW, Australia; Institute of Medical Physics, School of Physics, University of Sydney, Sydney, NSW, Australia. FAU - Batumalai, Vikneswary AU - Batumalai V AD - Liverpool and Macarthur Cancer Therapy Centres, Liverpool, NSW, Australia; Ingham Institute for Applied Medical Research, Liverpool Hospital, Sydney, NSW, Australia; South Western Sydney Clinical School, University of New South Wales, Sydney, NSW, Australia. FAU - Delaney, Geoff P AU - Delaney GP AD - Liverpool and Macarthur Cancer Therapy Centres, Liverpool, NSW, Australia; Ingham Institute for Applied Medical Research, Liverpool Hospital, Sydney, NSW, Australia; South Western Sydney Clinical School, University of New South Wales, Sydney, NSW, Australia; School of Medicine, University of Western Sydney, Sydney, NSW, Australia. FAU - Boxer, Miriam M AU - Boxer MM AD - Liverpool and Macarthur Cancer Therapy Centres, Liverpool, NSW, Australia; South Western Sydney Clinical School, University of New South Wales, Sydney, NSW, Australia. FAU - Yap, Mei Ling AU - Yap ML AD - Liverpool and Macarthur Cancer Therapy Centres, Liverpool, NSW, Australia; Ingham Institute for Applied Medical Research, Liverpool Hospital, Sydney, NSW, Australia; South Western Sydney Clinical School, University of New South Wales, Sydney, NSW, Australia; School of Medicine, University of Western Sydney, Sydney, NSW, Australia. FAU - Ahern, Verity AU - Ahern V AD - Crown Princess Mary Cancer Care Centre, Westmead Hospital, NSW, Australia. FAU - Chan, Christine AU - Chan C AD - Department of Radiology, Liverpool Hospital, NSW, Australia. FAU - David, Steven AU - David S AD - Peter MacCallum Cancer Centre, Melbourne, VIC, Australia. FAU - Dimigen, Marion AU - Dimigen M AD - Department of Radiology, Liverpool Hospital, NSW, Australia. FAU - Harvey, Jennifer A AU - Harvey JA AD - School of Medicine, University of Queensland, QLD, Australia; Princess Alexandra Hospital, QLD, Australia. FAU - Koh, Eng-Siew AU - Koh ES AD - Liverpool and Macarthur Cancer Therapy Centres, Liverpool, NSW, Australia; Ingham Institute for Applied Medical Research, Liverpool Hospital, Sydney, NSW, Australia; South Western Sydney Clinical School, University of New South Wales, Sydney, NSW, Australia. FAU - Lim, Karen AU - Lim K AD - Liverpool and Macarthur Cancer Therapy Centres, Liverpool, NSW, Australia; South Western Sydney Clinical School, University of New South Wales, Sydney, NSW, Australia. FAU - Papadatos, George AU - Papadatos G AD - Liverpool and Macarthur Cancer Therapy Centres, Liverpool, NSW, Australia. FAU - Lazarus, Elizabeth AU - Lazarus E AD - Department of Radiology, Liverpool Hospital, NSW, Australia. FAU - Descellar, Joseph AU - Descellar J AD - Ingham Institute for Applied Medical Research, Liverpool Hospital, Sydney, NSW, Australia; South Western Sydney Clinical School, University of New South Wales, Sydney, NSW, Australia. FAU - Metcalfe, Peter AU - Metcalfe P AD - Centre for Medical Radiation Physics, Faculty of Engineering and Information Sciences, University of Wollongong, Wollongong, NSW, Australia; Liverpool and Macarthur Cancer Therapy Centres, Liverpool, NSW, Australia; Ingham Institute for Applied Medical Research, Liverpool Hospital, Sydney, NSW, Australia. FAU - Holloway, Lois AU - Holloway L AD - Centre for Medical Radiation Physics, Faculty of Engineering and Information Sciences, University of Wollongong, Wollongong, NSW, Australia; Liverpool and Macarthur Cancer Therapy Centres, Liverpool, NSW, Australia; Ingham Institute for Applied Medical Research, Liverpool Hospital, Sydney, NSW, Australia; South Western Sydney Clinical School, University of New South Wales, Sydney, NSW, Australia. LA - eng PT - Journal Article DEP - 20170714 PL - United States TA - Pract Radiat Oncol JT - Practical radiation oncology JID - 101558279 SB - IM MH - Adult MH - Aged MH - Breast Neoplasms/diagnostic imaging/*radiotherapy MH - Female MH - Humans MH - Magnetic Resonance Imaging/*methods MH - Middle Aged MH - Patient Positioning/*methods MH - Tomography, X-Ray Computed/*methods EDAT- 2017/10/11 06:00 MHDA- 2018/09/20 06:00 CRDT- 2017/10/11 06:00 PHST- 2017/07/03 00:00 [received] PHST- 2017/07/11 00:00 [accepted] PHST- 2017/10/11 06:00 [pubmed] PHST- 2018/09/20 06:00 [medline] PHST- 2017/10/11 06:00 [entrez] AID - S1879-8500(17)30202-3 [pii] AID - 10.1016/j.prro.2017.07.007 [doi] PST - ppublish SO - Pract Radiat Oncol. 2018 May-Jun;8(3):e87-e97. doi: 10.1016/j.prro.2017.07.007. Epub 2017 Jul 14.