Hypofractionated Radiation Therapy for Breast Cancer: A Unit Review in Alignment with International Guidelines

Randomized trials and international guidelines endorse hypofractionated whole-breast irradiation (HF-WBI) as standard of care for early breast cancer, offering equivalent tumour control with shorter treatment times and reduced system burden. In South Africa, where access and throughput are critical, real-world uptake is particularly relevant. This review evaluates our centre's adoption of HF-WBI and adherence to guideline-based practice.

We retrospectively reviewed all breast cancer patients referred for radiotherapy from 2018-2024, stratifying fractionation as conventional WBI (CF-WBI; ~50 Gy/25 fractions), hypofractionation (40.05 Gy/15 or 42.5 Gy/16), and ultra-hypofractionation (≈26 Gy/5). Among those receiving breast-conserving therapy (BCT), we assessed annual HF-WBI adoption, age distribution (<50 vs. ≥50 years), and boost use.

Across yearly datasets, HF-WBI increased steadily and substantially. In 2018, HF-WBI accounted for 17/138 CF/HF cases (12.3%). Uptake rose through 2019 (21.0%), 2020 (27.1%), 2021 (43.4%), 2022 (38.6%), 2023 (54.6%), and reached 82.4% in 2024 (103 HF vs. 22 CF). Ultra-hypofractionation (≈26 Gy/5) appeared from 2022 onward at low but increasing levels (e.g., 6 cases in 2024). Boost delivery was used across schedules; HF-WBI frequently included a boost (e.g., 59 cases in 2023; 70 in 2024), indicating protocol flexibility without abandoning shorter courses. Importantly, HF-WBI was used in both younger and older patients (e.g., 2024: <50 y = 32; ≥50 y = 70 within HF cases), reflecting rising clinician confidence across age groups as guideline-concordant practice matured.

Our multi-year review demonstrates a decisive transition from conventional to HF breast RT, with HF-WBI becoming the predominant regimen by 2024. Real-world implementation was feasible with sustained boost utilisation and broad age inclusivity, aligning with international guidelines while improving patient convenience and departmental efficiency. Wider adoption of HF-WBI-and selective use of ultra-hypofractionation- can expand equitable access and support service sustainability in resource-constrained health systems.

1. Adopt "HF-by-default" for eligible BCT patients, requiring a documented exception for CF-WBI. 2. Scale a FAST-Forward pathway (≈26 Gy/5) where clinically appropriate with clear selection criteria. 3. Standardise boost indications in HF schedules (e.g., 10-16 Gy in 4-8 fractions). 4. Embed age-agnostic eligibility in MDM checklists to avoid age-based bias against HF. 5. Bundle HF-WBI with DIBH planning QA for left-sided cases to maintain cardiac/lung constraints. 6. Implement a KPI dashboard tracking HF share, median treatment days, boost rate, and re-planning rate. 7. Update patient-facing education to explain HF schedules and boost delivery, improving adherence.