The Salzburg concept of intraoperative radiotherapy for breast cancer: Results and considerations

Abstract

Aim of this study is to show that ipsilateral breast tumor recurrence (IBTR) after breast conserving surgery can be reduced by proper surgery and modern radiotherapy techniques. Three hundred and seventy eight women with stage I or II breast cancer had breast conserving surgery and received 51-56.1 Gy of postoperative radiation to the whole breast in 1.7 Gy fractions, but patients received different boost strategies. Group 1 (n 5 188) received electron boost radiation of 12 Gy subsequent to the irradiation to the whole breast, group 2 (n 5 190) received intraoperative electron boost radiation of 9 Gy directly to the tumor bed, followed by whole breast irradiation. After a median follow up period of 81.0 months in group 1 and a median follow up period of 51.1 months in group 2, 12 IBTRs (6.4%) could be observed in group 1 and no IBTR could be observed in group 2 (0.0%). The 5-year actuarial rates of IBTR were 4.3% (95% CI, 1.9-8.3%) and 0.0% (95% CI, 0.0-1.9%), respectively (p 5 0.0018). The 5-year actuarial rates of distant recurrence were 8.6% (95% CI, 4.9-13.5%) and 4.2% (95% CI, 1.8-8.2%), respectively (p 5 0.08). The 5 year disease-free survival rates were 90.9% (95% CI, 85.8-94.7%) in group 1 and 95.8% (95% CI, 91.8-98.2%) in group 2 (p 5 0.064). Immediate IORT-boost and whole breast irradiation yields excellent local control at 5 years, and was associated with a statistically significant decreased rate of IBTR compared with a similar cohort of patients treated with whole breast irradiation and conventional electron boost. ' 2005 Wiley-Liss, Inc.

Intraoperative Electron Radiotherapy (IOERT) in the Treatment of Primary Breast Cancer

“…Furthermore, in a retrospective matched-pair analysis, 188 patients with external electron boost (6 × 2 Gy) were compared to 190 IOERT patients from the Salzburg cohort [24]. At 5-year follow up, the in-breast recurrence rate in the external electron boost group was 4.3% compared to 0% in the IOERT group.…”

Intraoperative Radiotherapy for Early Breast Cancer

“…With regard to another concept of full-dose intraoperative radiotherapy, an anticipated boost during operation has been studied (Reitsamer et al, 2002;Reitsamer et al, 2006). A single dose of 9 Gy was applied to the 90% reference isodose with energies ranging from 4 to 15 MeV, using round applicator tubes 4-8 cm in diameter.…”

“…The advantages are follows. 1) To complete skin sparing, 2) the precise application of the boost directly to the tumor bed with a homogeneous tissue radiation and 3) to reduce postoperative radiation time for 7-10 days (time of postoperative boost radiotherapy) (Reitsamer, et al, 2002;Reitsamer, et al, 2006).…”

Local Therapy of Early Breast Cancer*

“…4 European trials initiating partial breast irradiation before 1990 showed an annual local recurrence rate of up to 10%, while more recent series have demonstrated an annual local recurrence rate below 1% [31]. The Fitzal/Riedl/Jakesz Salzburg trial showed improved local recurrence rates in partial breast-irradiated patients compared with whole breast-irradiated patients [32]. Patients in the trials differed in terms of grading, tumour size and age, which may have contributed to the better results in the later trials.…”