Results with accelerated partial breast irradiation in terms of estrogen receptor, progesterone receptor, and human growth factor receptor 2 status

Int J Radiat Oncol Biol Phys. 2010 Nov 1;78(3):799-803. doi: 10.1016/j.ijrobp.2009.08.081.

Abstract

Purpose: To report our results with accelerated partial breast irradiation (APBI) in terms of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER-2/neu) status.

Methods and materials: Between February 2003 and June 2009, 209 women with early-stage breast carcinomas were treated with APBI using multicatheter, MammoSite, or Contura brachytherapy to 34 Gy in 10 fractions twice daily over 5-7 days. Three patient groups were defined by receptor status: Group 1: ER or PR (+) and HER-2/neu (-) (n = 180), Group 2: ER and PR (-) and HER-2/neu (+) (n = 10), and Group 3: ER, PR, and HER-2/neu (-) (triple negative breast cancer, n = 19). Median follow-up was 22 months.

Results: Group 3 patients had significantly higher Scarff-Bloom-Richardson scores (p < 0.001). The 3-year ipsilateral breast tumor control rates for Groups 1, 2, and 3 were 99%, 100%, and 100%, respectively (p = 0.15). Group 3 patients tended to experience relapse in distant sites earlier than did non-Group 3 patients. The 3-year relapse-free survival rates for Groups 1, 2, and 3 were 100%, 100%, and 81%, respectively (p = 0.046). The 3-year cause-specific and overall survival rates for Groups 1, 2, and 3 were 100%, 100%, and 89%, respectively (p = 0.002).

Conclusions: Triple negative breast cancer patients typically have high-grade tumors with significantly worse relapse-free, cause-specific, and overall survival. Longer follow-up will help to determine whether these patients also have a higher risk of ipsilateral breast tumor relapse.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Brachytherapy / adverse effects
  • Brachytherapy / methods
  • Breast Neoplasms / chemistry*
  • Breast Neoplasms / ethnology
  • Breast Neoplasms / mortality
  • Breast Neoplasms / pathology
  • Breast Neoplasms / radiotherapy*
  • Breast Neoplasms / surgery
  • Chi-Square Distribution
  • Dose Fractionation, Radiation
  • Female
  • Humans
  • Mastectomy, Segmental
  • Middle Aged
  • Neoplasm Proteins / analysis*
  • Neoplasm Recurrence, Local / mortality
  • Neoplasm Recurrence, Local / prevention & control
  • Receptor, ErbB-2 / analysis*
  • Receptors, Estrogen / analysis*
  • Receptors, Progesterone / analysis*
  • Regression Analysis
  • Statistics, Nonparametric
  • Survival Rate

Substances

  • Neoplasm Proteins
  • Receptors, Estrogen
  • Receptors, Progesterone
  • Receptor, ErbB-2