Analysis of treatment efficacy, cosmesis, and toxicity using the MammoSite breast brachytherapy catheter to deliver accelerated partial-breast irradiation: the william beaumont hospital experience

Int J Radiat Oncol Biol Phys. 2007 Sep 1;69(1):32-40. doi: 10.1016/j.ijrobp.2007.02.026. Epub 2007 Apr 30.

Abstract

Purpose: To review our institution's experience of treating patients with the MammoSite (Cytyc Corp., Marlborough, MA) breast brachytherapy catheter to deliver accelerated partial-breast irradiation (APBI), for determining short-term treatment efficacy, cosmesis, and toxicity.

Methods and materials: From January 2000 to April 2006, 80 patients treated with breast-conserving therapy (BCT) received adjuvant radiation using the MammoSite (34 Gy in 3.4-Gy fractions prescribed to 1.0 cm from the balloon surface). Twenty-three patients (29%) had Stage 0 breast cancer, 46 (57%) had Stage I breast cancer, and 11 (14%) had Stage II breast cancer. The median follow-up was 22.1 months.

Results: Two ipsilateral breast-tumor recurrences (IBTRs) (2.5%) developed for a 3-year actuarial rate of 2.9% (no regional failures were observed). On molecular-based clonality assay evaluation, both recurrences were clonally related. Younger age at diagnosis was the only variable associated with IBTR (continuous variable, p = 0.044; categorical variable [<55 years vs. >/=55 years], p = 0.012). The percentages of patients with good/excellent cosmetic results at 12 and 36 months were 96.9% and 88.2%, respectively (p = NS). Patients with applicator-to-skin spacing <7 mm and those who received adjuvant systemic chemotherapy exhibited lower rates of good/excellent cosmetic results, though the association was not statistically significant. The overall incidence of symptomatic seromas and any seromas was 10% and 45%, respectively. The overall incidence of fat necrosis and infections was 8.8% and 11.3%, respectively.

Conclusions: Early-stage breast-cancer patients treated with adjuvant APBI using the MammoSite catheter exhibited a 3-year treatment efficacy, cosmesis, and toxicity similar to those observed with other forms of interstitial APBI at this length of follow-up.

Publication types

  • Evaluation Study

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Analysis of Variance
  • Brachytherapy / instrumentation
  • Brachytherapy / methods*
  • Breast / pathology
  • Breast / radiation effects*
  • Breast / surgery
  • Breast Neoplasms / mortality
  • Breast Neoplasms / pathology
  • Breast Neoplasms / radiotherapy*
  • Breast Neoplasms / surgery
  • Carcinoma in Situ / pathology
  • Carcinoma in Situ / radiotherapy
  • Carcinoma in Situ / surgery
  • Carcinoma, Ductal, Breast / pathology
  • Carcinoma, Ductal, Breast / radiotherapy
  • Carcinoma, Ductal, Breast / surgery
  • Dose Fractionation, Radiation
  • Esthetics
  • Female
  • Follow-Up Studies
  • Humans
  • Mastectomy, Segmental
  • Middle Aged
  • Neoplasm Recurrence, Local / mortality
  • Neoplasm Recurrence, Local / pathology
  • Proportional Hazards Models
  • Radiation Injuries / pathology
  • Treatment Outcome