title: Five-year local control in a phase II study of hypofractionated intensity modulated radiation therapy with an incorporated boost for early stage breast cancer.
abstract: OBJECTIVE
  Conventional radiation fractionation of 1.8-2 Gy per day for early stage breast cancer requires daily treatment for 6-7 weeks. We report the 5-year results of a phase II study of intensity modulated radiation therapy (IMRT), hypofractionation, and incorporated boost that shortened treatment time to 4 weeks.
  
  
  METHODS
  The study design was phase II with a planned accrual of 75 patients. Eligibility included patients aged≥18 years, Tis-T2, stage 0-II, and breast conservation. Photon IMRT and an incorporated boost was used, and the whole breast received 2.25 Gy per fraction for a total of 45 Gy, and the tumor bed received 2.8 Gy per fraction for a total of 56 Gy in 20 treatments over 4 weeks. Patients were followed every 6 months for 5 years.
  
  
  RESULTS
  Seventy-five patients were treated from December 2003 to November 2005. The median follow-up was 69 months. Median age was 52 years (range, 31-81). Median tumor size was 1.4 cm (range, 0.1-3.5). Eighty percent of tumors were node negative; 93% of patients had negative margins, and 7% of patients had close (>0 and <2 mm) margins; 76% of cancers were invasive ductal type: 15% were ductal carcinoma in situ, 5% were lobular, and 4% were other histology types. Twenty-nine percent of patients 29% had grade 3 carcinoma, and 20% of patients had extensive in situ carcinoma; 11% of patients received chemotherapy, 36% received endocrine therapy, 33% received both, and 20% received neither. There were 3 instances of local recurrence for a 5-year actuarial rate of 2.7%.
  
  
  CONCLUSIONS
  This 4-week course of hypofractionated radiation with incorporated boost was associated with excellent local control, comparable to historical results of 6-7 weeks of conventional whole-breast fractionation with sequential boost.
authors.affiliation: Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA. Gary.Freedman@uphs.upenn.edu
authors.forename: Gary M
authors.initials: GM
authors.lastname: Freedman
authors.forename: Penny R
authors.initials: PR
authors.lastname: Anderson
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Bleicher
authors.forename: Samuel
authors.initials: S
authors.lastname: Litwin
authors.forename: Tianyu
authors.initials: T
authors.lastname: Li
authors.forename: Ramona F
authors.initials: RF
authors.lastname: Swaby
authors.forename: Chang-Ming Charlie
authors.initials: CM
authors.lastname: Ma
authors.forename: Jinsheng
authors.initials: J
authors.lastname: Li
authors.forename: Elin R
authors.initials: ER
authors.lastname: Sigurdson
authors.forename: Deborah
authors.initials: D
authors.lastname: Watkins-Bruner
authors.forename: Monica
authors.initials: M
authors.lastname: Morrow
authors.forename: Lori J
authors.initials: LJ
authors.lastname: Goldstein
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000473:pathology* / Q000532:radiotherapy* / Q000601:surgery; D002278:Carcinoma in Situ / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D003131:Combined Modality Therapy / Q000379:methods; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D009367:Neoplasm Staging; D016609:Neoplasms, Second Primary / Q000473:pathology; D017785:Photons / Q000627:therapeutic use; D011788:Quality of Life; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods*; D012867:Skin / Q000528:radiation effects; D013997:Time Factors; D047368:Tumor Burden