A Phase II trial of brachytherapy alone after lumpectomy for select breast cancer: tumor control and survival outcomes of RTOG 95-17

Int J Radiat Oncol Biol Phys. 2008 Oct 1;72(2):467-73. doi: 10.1016/j.ijrobp.2007.12.056. Epub 2008 Mar 4.

Abstract

Purpose: Radiation Therapy Oncology Group 95-17 is a prospective Phase II cooperative group trial of accelerated partial breast irradiation (APBI) alone using multicatheter brachytherapy after lumpectomy in select early-stage breast cancers. Tumor control and survival outcomes are reported.

Methods and materials: Eligibility criteria included Stage I/II breast carcinoma confirmed to be <3 cm, unifocal, invasive nonlobular histology with zero to three positive axillary nodes without extracapsular extension. APBI treatment was delivered with either low-dose-rate (LDR) (45 Gy in 3.5-5 days) or high-dose-rate (HDR) brachytherapy (34 Gy in 10 twice-daily fractions over 5 days). End points evaluated included in-breast control, regional control, mastectomy-free rate, mastectomy-free survival, disease-free survival, and overall survival. The study was designed to analyze the HDR and LDR groups separately and without comparison.

Results: Between 1997 and 2000, 100 patients were accrued and 99 were eligible; 66 treated with HDR brachytherapy and 33 treated with LDR brachytherapy. Eighty-seven patients had T1 lesions and 12 had T2 lesions. Seventy-nine were pathologically N0 and 20 were N1. Median follow-up in the HDR group is 6.14 years with the 5-year estimates of in-breast, regional, and contralateral failure rates of 3%, 5%, and 2%, respectively. The LDR group experienced similar results with a median follow-up of 6.22 years. The 5-year estimates of in-breast, regional, and contralateral failure rates of 6%, 0%, and 6%, respectively.

Conclusion: Patients treated with multicatheter partial breast brachytherapy in this trial experienced excellent in-breast control rates and overall outcome that compare with reports from APBI studies with similar extended follow-up.

Publication types

  • Clinical Trial, Phase II
  • Multicenter Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Aged
  • Brachytherapy / methods*
  • Brachytherapy / standards
  • Breast Neoplasms / radiotherapy*
  • Breast Neoplasms / surgery*
  • Female
  • Follow-Up Studies
  • Humans
  • Mastectomy, Segmental*
  • Middle Aged
  • Prospective Studies
  • Quality Control
  • Radiotherapy Dosage
  • Survival Analysis