title: Long-Term Cancer Outcomes From Study NRG Oncology/RTOG 9517: A Phase 2 Study of Accelerated Partial Breast Irradiation With Multicatheter Brachytherapy After Lumpectomy for Early-Stage Breast Cancer.
abstract: To examine 10-year rates of local, regional, and distant recurrences, patterns of recurrence, and survival rates for breast cancer patients enrolled on Study NRG Oncology/Radiation Therapy Oncology Group 9517, a multi-institutional prospective trial that studied one of the earliest methods of accelerated partial breast irradiation (APBI), multicatheter brachytherapy (MCT).
  
  
  
  Eligibility included stage I/II unifocal breast cancer <3 cm in size after lumpectomy with negative surgical margins and 0 to 3 positive axillary nodes without extracapsular extension. The APBI dose delivered was 34 Gy in 10 twice-daily fractions over 5 days for high-dose-rate (HDR); and 45 Gy in 3.5 to 5 days for low-dose-rate (LDR) brachytherapy. The primary endpoint was HDR and LDR MCT reproducibility. This analysis focuses on long-term ipsilateral breast recurrence (IBR), contralateral breast cancer events (CBE), regional recurrence (RR), and distant metastases (DM), disease-free, and overall survival.
  
  
  
  The median follow-up was 12.1 years. One hundred patients were accrued from 1997 to 2000; 98 were evaluable; 65 underwent HDR and 33 LDR MCT. Median age was 62 years; 88% had T1 tumors; 81% were pN0. Seventy-seven percent were estrogen receptor and/or progesterone receptor positive; 33% received adjuvant chemotherapy and 64% antiendocrine therapy. There have been 4 isolated IBRs and 1 IBR with RR, for 5.2% 10-year IBR without DM. There was 1 isolated RR, 1 with IBR, and 1 with a CBE, for 3.1% 10-year RR without DM. The 10-year CBE rate was 4.2%, with 5 total events. Eleven patients have developed DM, 8 have died of breast cancer, and 22 have died from other causes. The 10-year DFS and OS rates are 69.8% and 78.0%, respectively.
  
  
  
  This multi-institutional, phase 2 trial studying MCT-APBI continues to report durable in-breast cancer control rates with long-term follow-up.
authors.affiliation: Department of Radiation Oncology, The James, Ohio State University, Columbus, Ohio. Electronic address: Julia.White@osumc.edu.
authors.forename: Julia
authors.initials: J
authors.lastname: White
authors.affiliation: NRG Oncology Statistics and Data Management Center, Philadelphia, Pennsylvania.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Winter
authors.affiliation: Department of Radiation Oncology, Arizona Breast Cancer Specialists, Scottsdale, Arizona.
authors.forename: Robert R
authors.initials: RR
authors.lastname: Kuske
authors.affiliation: Department of Radiation Oncology, Oschner Clinic, New Orleans, Louisiana.
authors.forename: John S
authors.initials: JS
authors.lastname: Bolton
authors.affiliation: Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia.
authors.forename: Douglas W
authors.initials: DW
authors.lastname: Arthur
authors.affiliation: Department of Radiation Oncology, Oschner Clinic, New Orleans, Louisiana.
authors.forename: Troy
authors.initials: T
authors.lastname: Scroggins
authors.affiliation: Department of Radiation Oncology, University of Colorado Denver, Aurora, Colorado.
authors.forename: Rachel A
authors.initials: RA
authors.lastname: Rabinovitch
authors.affiliation: Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin.
authors.forename: Tracy
authors.initials: T
authors.lastname: Kelly
authors.affiliation: Mount Sinai Comprehensive Cancer Center, Miami, Florida.
authors.forename: Leonard M
authors.initials: LM
authors.lastname: Toonkel
authors.affiliation: Department of Radiation Oncology, Botsford Hospital, Farmington Hills, Michigan.
authors.forename: Frank A
authors.initials: FA
authors.lastname: Vicini
authors.affiliation: Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York.
authors.forename: Beryl
authors.initials: B
authors.lastname: McCormick
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000401:mortality* / Q000706:statistics & numerical data; D001943:Breast Neoplasms / Q000401:mortality* / Q000473:pathology / Q000628:therapy*; D002406:Catheterization, Peripheral / Q000401:mortality / Q000706:statistics & numerical data; D003131:Combined Modality Therapy / Q000401:mortality / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D015412:Mastectomy, Segmental / Q000401:mortality* / Q000706:statistics & numerical data; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality* / Q000473:pathology / Q000517:prevention & control; D009367:Neoplasm Staging; D015995:Prevalence; D000069473:Radiation Dose Hypofractionation; D012307:Risk Factors; D015996:Survival Rate; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology