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Title: Quantifying dose to the reconstructed breast: Can we adequately treat?

Abstract

To evaluate how immediate reconstruction (IR) impacts postmastectomy radiotherapy (PMRT) dose distributions to the reconstructed breast (RB), internal mammary nodes (IMN), heart, and lungs using quantifiable dosimetric end points. 3D conformal plans were developed for 20 IR patients, 10 autologous reconstruction (AR), and 10 expander-implant (EI) reconstruction. For each reconstruction type, 5 right- and 5 left-sided reconstructions were selected. Two plans were created for each patient, 1 with RB coverage alone and 1 with RB + IMN coverage. Left-sided EI plans without IMN coverage had higher heart Dmean than left-sided AR plans (2.97 and 0.84 Gy, p = 0.03). Otherwise, results did not vary by reconstruction type and all remaining metrics were evaluated using a combined AR and EI dataset. RB coverage was adequate regardless of laterality or IMN coverage (Dmean 50.61 Gy, D95 45.76 Gy). When included, IMN Dmean and D95 were 49.57 and 40.96 Gy, respectively. Mean heart doses increased with left-sided treatment plans and IMN inclusion. Right-sided treatment plans and IMN inclusion increased mean lung V{sub 20}. Using standard field arrangements and 3D planning, we observed excellent coverage of the RB and IMN, regardless of laterality or reconstruction type. Our results demonstrate that adequate doses can bemore » delivered to the RB with or without IMN coverage.« less

Authors:
; ; ;  [1];  [1]
  1. Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States)
Publication Date:
OSTI Identifier:
22262791
Resource Type:
Journal Article
Resource Relation:
Journal Name: Medical Dosimetry; Journal Volume: 38; Journal Issue: 1; Other Information: Copyright (c) 2013 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
61 RADIATION PROTECTION AND DOSIMETRY; IMPLANTS; MAMMARY GLANDS; PLANNING; RADIATION DOSE DISTRIBUTIONS; RADIATION DOSES; RADIOTHERAPY; SURGERY

Citation Formats

Chung, Eugene, Marsh, Robin B., Griffith, Kent A., Moran, Jean M., and Pierce, Lori J., E-mail: ljpierce@umich.edu. Quantifying dose to the reconstructed breast: Can we adequately treat?. United States: N. p., 2013. Web. doi:10.1016/J.MEDDOS.2012.06.002.
Chung, Eugene, Marsh, Robin B., Griffith, Kent A., Moran, Jean M., & Pierce, Lori J., E-mail: ljpierce@umich.edu. Quantifying dose to the reconstructed breast: Can we adequately treat?. United States. doi:10.1016/J.MEDDOS.2012.06.002.
Chung, Eugene, Marsh, Robin B., Griffith, Kent A., Moran, Jean M., and Pierce, Lori J., E-mail: ljpierce@umich.edu. 2013. "Quantifying dose to the reconstructed breast: Can we adequately treat?". United States. doi:10.1016/J.MEDDOS.2012.06.002.
@article{osti_22262791,
title = {Quantifying dose to the reconstructed breast: Can we adequately treat?},
author = {Chung, Eugene and Marsh, Robin B. and Griffith, Kent A. and Moran, Jean M. and Pierce, Lori J., E-mail: ljpierce@umich.edu},
abstractNote = {To evaluate how immediate reconstruction (IR) impacts postmastectomy radiotherapy (PMRT) dose distributions to the reconstructed breast (RB), internal mammary nodes (IMN), heart, and lungs using quantifiable dosimetric end points. 3D conformal plans were developed for 20 IR patients, 10 autologous reconstruction (AR), and 10 expander-implant (EI) reconstruction. For each reconstruction type, 5 right- and 5 left-sided reconstructions were selected. Two plans were created for each patient, 1 with RB coverage alone and 1 with RB + IMN coverage. Left-sided EI plans without IMN coverage had higher heart Dmean than left-sided AR plans (2.97 and 0.84 Gy, p = 0.03). Otherwise, results did not vary by reconstruction type and all remaining metrics were evaluated using a combined AR and EI dataset. RB coverage was adequate regardless of laterality or IMN coverage (Dmean 50.61 Gy, D95 45.76 Gy). When included, IMN Dmean and D95 were 49.57 and 40.96 Gy, respectively. Mean heart doses increased with left-sided treatment plans and IMN inclusion. Right-sided treatment plans and IMN inclusion increased mean lung V{sub 20}. Using standard field arrangements and 3D planning, we observed excellent coverage of the RB and IMN, regardless of laterality or reconstruction type. Our results demonstrate that adequate doses can be delivered to the RB with or without IMN coverage.},
doi = {10.1016/J.MEDDOS.2012.06.002},
journal = {Medical Dosimetry},
number = 1,
volume = 38,
place = {United States},
year = 2013,
month = 4
}
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