Aims

In response to the publication of new data from key randomised controlled trials (RCTs)Cancer Australia has updated its evidence-based clinical practice guidelines for the use of hypofractionated radiotherapy for early (operable) breast cancer.

Methods

A Working Group oversaw the update, with representation from the RANZCR Faculty of Radiation Oncology, Breast Surgeons Australia New Zealand, Breast Cancer Network Australia, and a breast care nurse. Systematic literature reviews addressed questions regarding the relative effectiveness and safety of hypofractionated radiotherapy (HFRT) versus conventionally fractionated radiotherapy (CFRT), the use of tumour bed boost doses, and the potential for cardiac toxicity when delivering HFRT to left-sided tumours.

Results

Key findings from the updated primary evidence base (six RCTs including 8,368 patients, followed for up to 17 years) is that in selected patients HFRT and CFRT are associated with equivalent efficacy (overall survival, progression-free survival, loco-regional recurrence) and safety (including cosmetic outcomes). Recent RCT evidence demonstrates no significant difference between HFRT and CFRT in locoregional relapse between grade 1/2 and  3 tumours. Observational data show no difference in 15-year cardiac mortality or cumulative cardiac morbidity, between fractionation schedules. There is insufficient evidence to inform the safety and efficacy of hypofractionated chest wall irradiation in women who have undergone mastectomy or for women with DCIS.

Conclusions

In patients aged 50 years or older, with early breast cancer and no lymph node involvement (pathological stage T1-T2, N0, M0) regardless of tumour grade, who have undergone breast-conserving surgery with clear surgical margins and who require post-operative whole breast radiotherapy, HFRT is a suitable alternative to CFRT, and should be offered where appropriate. This recommendations is graded ‘A’ meaning the body of evidence can be trusted to guide practice. Practice Points were developed regarding the use of tumour bed boost doses, and heart-sparing protocols.