Weekly radiotherapy in elderly breast cancer patients: a comparison between two hypofractionation schedules

Purpose Weekly irradiation in breast cancer in elderly patients is a treatment option, whose tolerance may be influenced by the fractionation used. The objective of this study is to compare the tolerance and long-term side effects of two different fractionations. Materials and methods 47 elderly patients were recruited after conservative or radical treatment that also received irradiation with a dose per fraction of 6.25 Gy or 5 Gy for one session per week, 6 sessions in total. The long-term tolerance results are compared by assessing toxicity using CTCAE version 5.0 scales for dermatitis, telangectasia, fibrosis and pain of the irradiated breast. In addition, objective parameters of skin status (erythema, hyperpigmentation, elasticity and hydration) by a multi-probe MultiSkin Test-Center system were obtained and compared between groups. Results After an average follow-up of 5 years, all patients were free of disease and with complete local control. A total of 20 patients with 6.25 Gy fractionation and 27 patients with 5 Gy fractionation have been included. Patients treated with lower fractionation had a lower incidence of dermatitis, telangectasia, fibrosis, or local pain. The decrease in elasticity measured by the multi-probe system was smaller with the fractionation of 5 Gy. No differences were observed in the other objective parameters. Conclusion Weekly irradiation with 5 Gy fractionation is better tolerated than with higher fractionation.