Aristei C, et al. – Aim was to elucidate partial breast irradiation with interstitial multi–catheter high–dose–rate brachytherapy. Findings of this work indicated an association of accelerated partial breast irradiation (APBI) with interstitial multi–catheter brachytherapy with good outcomes, low relapse, and toxicity rates. Few events during this long–term follow–up precluded identifying specific features of patients at risk of relapse. These events outlined the need for a large data–base.

Methods

• APBI (4 Gy, twice daily; total dose 32 Gy) was administered to 240 patients.

Results

• As per observations, median follow-up was 96 months.
• At a median of 73 months after APBI, recurrences in the treated breast developed in 8 patients (3.3%).
• 1.8% (95%CI: 0.6–4.3) and 6.6% (95%CI: 2.7–12.9) were the 5- and 10-year cumulative incidences.
• At a median of 28 months, regional recurrences developed in 5 patients (2%) and distant metastases developed in 8 (3.3%) at a median of 32.5 months.
• Researchers found breast cancer specific mortality in 6 patients (2.5%) at a median of 60 months.
• In 71 (29.6%) patients (G1 in 60 and G2 in 11), acute toxicity developed, which were mostly skin toxicity and hematomas.
• They noted late toxicity in 90 patients (37.5%), G1 in 97 cases and G2 in 11.
• In addition, some patients presented with more than one type of toxicity.
• Followed by fat necrosis (in 18 patients), teleangectasia and fibrosis were the most common (48 and 44 cases respectively).
• The only risk factor for breast fibrosis (p=0.007) was tamoxifen.
• The physicians judged cosmetic results as excellent in 174 (83.7%) patients, good in 25 (12%) fair in 8 (3.8%) and poor in 1 (0.5%).
• Moreover, 174 patients (83.7%) judged outcomes as excellent, 26 (12.4%) as good, 7 (3.4%) as fair and 1 (0.5%) as poor.
• This study reported good physician/patient agreement (weighted k-value 0.72).