title: Nation-Scale Adoption of Shorter Breast Radiation Therapy Schedules Can Increase Survival in Resource Constrained Economies: Results From a Markov Chain Analysis.
abstract: Hypofractionated whole breast irradiation and accelerated partial breast irradiation (APBI) offer women options for shorter courses of breast radiation therapy. The impact of these shorter schedules on the breast cancer populations of emerging economies with limited radiation therapy resources is unknown. We hypothesized that adoption of these schedules would improve throughput in the system and, by allowing more women access to life-saving treatments, improve patient survival within the system.
  
  
  
  We designed a Markov chain model to simulate the different health states that a postlumpectomy or postmastectomy patient could enter over the course of a 20-year follow-up period. Transition rates between health states were adapted from published data on recurrence rates. We used primary data from a tertiary care hospital in Lahore, Pakistan, to populate the model with proportional use of mastectomy versus breast conservation and to estimate the proportion of patients suitable for APBI. Sensitivity analyses on the use of APBI and relative efficacy of APBI were conducted to study the impact on the population.
  
  
  
  The shorter schedule resulted in more women alive and more women remaining without evidence of disease (NED) compared with the conventional schedule, with an absolute difference of about 4% and 7% at 15 years, respectively. Among women who had lumpectomies, the chance of remaining alive and with an intact breast was 62% in the hypofractionation model and 54% in the conventional fractionation model.
  
  
  
  Increasing throughput in the system can result in improved survival, improved chances of remaining without evidence of disease, and improved chances of remaining alive with a breast. These findings are significant and suggest that adoption of hypofractionation in emerging economies is not simply a question of efficiency and cost but one of access to care and patient survivorship.
authors.affiliation: Department of Radiation Oncology, Robert Wood Johnson Medical School/Cancer Institute of New Jersey, New Brunswick, New Jersey. Electronic address: atif.j.khan@rutgers.edu.
authors.forename: Atif J
authors.initials: AJ
authors.lastname: Khan
authors.affiliation: Suleman Dawood School of Business, Lahore University of Management Sciences, Lahore, Pakistan.
authors.forename: Raza
authors.initials: R
authors.lastname: Rafique
authors.affiliation: Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan.
authors.forename: Waleed
authors.initials: W
authors.lastname: Zafar
authors.affiliation: Department of Radiation Oncology, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Chirag
authors.initials: C
authors.lastname: Shah
authors.affiliation: Department of Radiation Oncology, Robert Wood Johnson Medical School/Cancer Institute of New Jersey, New Brunswick, New Jersey.
authors.forename: Bruce G
authors.initials: BG
authors.lastname: Haffty
authors.affiliation: Michigan HealthCare Professionals, Farmington Hills, Michigan.
authors.forename: Frank
authors.initials: F
authors.lastname: Vicini
authors.affiliation: Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan.
authors.forename: Arif
authors.initials: A
authors.lastname: Jamshed
authors.affiliation: Rutgers University School of Business, Newark, New Jersey.
authors.forename: Yao
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000401:mortality* / Q000532:radiotherapy* / Q000601:surgery; D002173:Cancer Care Facilities / Q000706:statistics & numerical data; D003906:Developing Countries; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008390:Markov Chains; D008408:Mastectomy / Q000401:mortality / Q000706:statistics & numerical data; D015412:Mastectomy, Segmental / Q000401:mortality / Q000706:statistics & numerical data; D008875:Middle Aged; D010154:Pakistan / Q000453:epidemiology; D011184:Postoperative Period; D000069473:Radiation Dose Hypofractionation; D011878:Radiotherapy / Q000379:methods / Q000706:statistics & numerical data; D015996:Survival Rate; D013997:Time Factors; D017211:Treatment Failure