title: Comparison of Mammographic Changes Across Three Different Fractionation Schedules for Early-Stage Breast Cancer.
abstract: As the use of hypofractionated breast radiation therapy (RT) increases, so will the need for long-term data on post-RT mammographic changes. The purpose of the present study was to longitudinally compare the incidence of common mammographic sequelae seen after breast conserving surgery and RT in patients treated with accelerated partial breast irradiation (APBI), hypofractionated whole breast irradiation (HWBI), and conventionally fractionated whole breast irradiation (WBI).
  
  
  
  Patients treated with either APBI or HWBI after breast conserving therapy and with ≥3 mammograms of the treated breast were identified. They were matched 1:1 by age ±5 years to patients treated with WBI. The mammograms were evaluated for common post-RT breast findings by a mammographer who was unaware of the treatment. The outcomes were analyzed using a cumulative logistic regression model; P<.05 indicated statistically significance.
  
  
  
  Of 89 patients treated with RT from 2006 to 2011, 29 had received APBI, 30 had received HWBI, and 30 had received WBI. Their median age was 60 years (range 33-83). A total of 605 mammograms were evaluated, with a median follow-up of 48 months. The treatment technique did not affect the severity of architectural distortion when the groups were evaluated longitudinally. The likelihood of finding skin thickening decreased with increasing follow-up duration (odds ratio 0.6; P<.001) adjusted for fractionation schemes. No differences were seen with respect to changes in skin thickening, fluid collections, or calcifications among the treatment groups, after adjustment for the follow-up time. The clinical characteristics, including age, race, T stage, and chemotherapy use, were not linked to the likelihood of finding several mammographic phenomena over time.
  
  
  
  Although specific post-treatment imaging findings evolved over time, RT fractionation did not alter the relative incidence or severity of architectural distortion, skin thickening, fluid collections, or calcifications. These findings will be useful to both radiologists and radiation oncologists when counseling patients regarding follow-up studies after RT.
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey and Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey.
authors.forename: Sibo
authors.initials: S
authors.lastname: Tian
authors.affiliation: Department of Radiology, Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey.
authors.forename: Lina F
authors.initials: LF
authors.lastname: Paster
authors.affiliation: Biometrics Division, Rutgers Cancer Institute of New Jersey, and Department of Biostatistics, Rutgers School of Public Health, Rutgers, New Jersey.
authors.forename: Sinae
authors.initials: S
authors.lastname: Kim
authors.affiliation: Division of Surgical Oncology, Rutgers Cancer Institute of New Jersey and Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey.
authors.forename: Laurie
authors.initials: L
authors.lastname: Kirstein
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey and Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey.
authors.forename: Bruce G
authors.initials: BG
authors.lastname: Haffty
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey and Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey.
authors.forename: Adam
authors.initials: A
authors.lastname: Ferro
authors.affiliation: Department of Radiology, Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey.
authors.forename: Judith
authors.initials: J
authors.lastname: Amorosa
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey and Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey. Electronic address: goyalsh@rutgers.edu.
authors.forename: Sharad
authors.initials: S
authors.lastname: Goyal
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D016015:Logistic Models; D008327:Mammography; D008875:Middle Aged; D009367:Neoplasm Staging