title: Cardiac dose sparing and avoidance techniques in breast cancer radiotherapy.
abstract: Breast cancer radiotherapy represents an essential component in the overall management of both early stage and locally advanced breast cancer. As the number of breast cancer survivors has increased, chronic sequelae of breast cancer radiotherapy become more important. While recently published data suggest a potential for an increase in cardiac events with radiotherapy, these studies do not consider the impact of newer radiotherapy techniques commonly utilized. Therefore, the purpose of this review is to evaluate cardiac dose sparing techniques in breast cancer radiotherapy. Current options for cardiac protection/avoidance include (1) maneuvers that displace the heart from the field such as coordinating the breathing cycle or through prone patient positioning, (2) technological advances such as intensity modulated radiation therapy (IMRT) or proton beam therapy (PBT), and (3) techniques that treat a smaller volume around the lumpectomy cavity such as accelerated partial breast irradiation (APBI), or intraoperative radiotherapy (IORT). While these techniques have shown promise dosimetrically, limited data on late cardiac events exist due to the difficulties of long-term follow up. Future studies are required to validate the efficacy of cardiac dose sparing techniques and may use surrogates for cardiac events such as biomarkers or perfusion imaging.
authors.affiliation: Department of Radiation Oncology, Summa Health System, Akron, United States.
authors.forename: Chirag
authors.initials: C
authors.lastname: Shah
authors.affiliation: Department of Radiation Oncology, Siteman Cancer Center, Washington University School of Medicine, St. Louis, United States.
authors.forename: Shahed
authors.initials: S
authors.lastname: Badiyan
authors.affiliation: Department of Radiation Oncology, Summa Health System, Akron, United States.
authors.forename: Sameer
authors.initials: S
authors.lastname: Berry
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey & Rutgers Robert Wood Johnson Medical School, New Brunswick, United States.
authors.forename: Atif J
authors.initials: AJ
authors.lastname: Khan
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey & Rutgers Robert Wood Johnson Medical School, New Brunswick, United States.
authors.forename: Sharad
authors.initials: S
authors.lastname: Goyal
authors.affiliation: Department of Radiation Oncology, Summa Health System, Akron, United States.
authors.forename: Kevin
authors.initials: K
authors.lastname: Schulte
authors.affiliation: Department of Oncology, Georgetown University School of Medicine, Washington DC United States.
authors.forename: Anish
authors.initials: A
authors.lastname: Nanavati
authors.affiliation: Department of Radiation Oncology, Summa Health System, Akron, United States.
authors.forename: Melanie
authors.initials: M
authors.lastname: Lynch
authors.affiliation: Michigan Healthcare Professionals/21st Century Oncology, Farmington Hills, United States. Electronic address: fvicini@rtsx.com.
authors.forename: Frank A
authors.initials: FA
authors.lastname: Vicini
mesh_terms: D001943:Breast Neoplasms / Q000532:radiotherapy*; D062485:Breath Holding; D066126:Cardiotoxicity / Q000209:etiology / Q000517:prevention & control; D005260:Female; D006331:Heart Diseases / Q000209:etiology / Q000517:prevention & control*; D006801:Humans; D007430:Intraoperative Care; D015412:Mastectomy, Segmental; D059351:Organ Sparing Treatments; D056888:Patient Positioning / Q000379:methods; D016684:Prone Position; D061766:Proton Therapy / Q000009:adverse effects / Q000379:methods*; D011832:Radiation Injuries / Q000209:etiology / Q000517:prevention & control*; D011874:Radiometry; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D018714:Radiotherapy, Adjuvant / Q000009:adverse effects / Q000379:methods; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods*
keywords: Breast cancer; Cardiac toxicity; Dose reduction; Radiation therapy; Respiratory gating