Introduction UK Standardization of Breast Radiotherapy(START)trials suggested that lower total doses of radiotherapy delivered in fewer fractions(40.05 Gy in 15 fractions)were as safe and effective as the historical 50 Gy in 25 fractions.The recent 26 Gy in 5 fractions regimen also compared favourably.The purpose was to retrospectively establish outcomes of a shorter hypofractionated schedule of adjuvant radiotherapy during COVID-19 pandemic for breast cancer patients at Tygerberg Hospital over one year (2020–2021),in terms of locoregional recurrence,distant metastasis,survival and side effects.

Methods This study was conducted as a retrospective chart review of breast cancer patients treated with radiotherapy at Tygerberg Hospital over the period of April to September 2020.Patients with stages I-IIIC invasive breast carcinoma scheduled for adjuvant radiotherapy were eligible.

Results Between 1st April and 30th September 2020,161 patients were screened from Tygerberg Hospital breast multidisciplinary team meeting.100 were eligible;44 were assigned to 40.05 Gy in 15-day schedule and 56 to 26 Gy in 5-day fraction schedule.Over a median follow-up period of 15 months,it was reported that only four patients(p = 0.206, 95% CI; -0.316 – 0.71)got locoregional recurrence and ten developed metastases(p = 0.691 (95% CI, - 0.235 – 0.157).16 patients passed away.No statistically significant difference was seen between schedules regarding side effect profile and survival analysis.

Conclusion/Implications 26 Gy in five fractions over one week was relatively equivalent to 40.05 Gy in fifteen fractions over three weeks for local tumour control and was as safe in terms of normal tissue effects up to 1 year for patients prescribed adjuvant breast radiotherapy after primary surgery.