Objective: To assess and compare the impact on skin reactions and cosmesis between hypofractionated whole breast and
conventional irradiation for early breast cancer.

Material and Method: Seventy-three patients with operable breast cancer (pT1-3pN0-1M0) who underwent breast-conserving
surgery were assigned for irradiation to either conventional arm (50 Gy in 25 fractions) with a sequential electron boost of
15-16 Gy over five weeks or hypofractionated arm (43.2 Gy in 16 fractions) with a concomitant electron boost of 0.6 Gy over
three weeks.

Results: At 3-week follow-up, skin toxicities in the hypofractionated arm were significantly worse than that seen in the
conventional arm, while at 6-week follow-up, the percentages of skin toxicities in the conventional arm were higher. After a
median follow-up of six months, there was no significant difference in skin toxicities between the two treatment groups. In
addition, there were no significant differences in the mean scores of cosmetic outcome for patients between two regimens.

Conclusion: This hypofractionated radiotherapy regimen of 43.2 Gy in 16 fractions with a concomitant electron boost
showed good results in terms of normal tissue effects and cosmesis. A long-term follow-up is needed to confirm these
favorable results.

Keywords: Skin toxicity, Cosmesis, Hypofractionated radiotherapy, Whole breast irradiation, Breast cancer