Acute Toxicity and 2-year Adverse Effects of 30 Gy in Five Fractions over 15 Days to Whole Breast after Local Excision of Early Breast Cancer

Abstract

Aims A pilot study was undertaken with the aim of documenting acute skin reactions and 2-year late adverse effects of a five-fraction course of adjuvant whole breast radiotherapy delivered over 15 days after local tumour excision of early breast cancer. Materials and methods Thirty women with early invasive breast cancer aged ≥50 years with a pathological tumour size <3 cm, complete microscopic resection, negative axillary node status and no requirement for cytotoxic therapy were prescribed 30 Gy in five fractions over 15 days to the whole breast using tangential 6–10 MV X-ray beams and three-dimensional dose compensation with written informed consent. Post-surgical baseline photographs of the breasts were taken, and acute skin erythema and moist desquamation were each scored weekly for 7 weeks using four-point graded scales (grade 0 = none, 1 = mild, 2 = moderate, 3 = severe). This was followed by an annual clinical assessment, including repeat photographs at 2 years. Results Nine patients (30%, 95% confidence interval 14.7–49.4%) developed grade 2 erythema, with the remaining 21 patients developing milder degrees of reaction. Four (13.3%, 95% confidence interval 3.7–30.7) patients developed moist desquamation, grade 1 in three women and grade 2 in the fourth. At 2 years after treatment, 23/30 (77%) patients scored no change in photographic breast appearance compared with the pre-treatment baseline; seven (23%, 95% confidence interval 9.9–42.3) scored a mild change in breast appearance, and none developed a marked change. After a mean follow-up of 3.1 years (standard deviation 0.37, range 2.1–3.9 years) there have been no ipsilateral local tumour relapses. Conclusions Further evaluation of a five-fraction regimen of adjuvant whole breast radiotherapy in a phase III randomised trial is justified, including a regimen delivered in a total of 5 days.