A critical review of randomized controlled trials on topical corticosteroids for the prevention of radiation dermatitis in breast cancer.

Introduction: Topical steroids have shown effectiveness in preventing radiation dermatitis (RD) in breast cancer patients in randomized controlled trials (RCTs). This review provides an in-depth analysis of the study methodology of these RCTs to review whether topical steroids should be employed in routine clinical practice.

Methods: A systematic literature search of MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials was conducted from database inception until May 31, 2024. RCTs comparing topical steroids with moisturizers or placebo for the prophylaxis of RD in breast cancer patients were included. The methodology of the RCTs, including how topical steroids were applied, whether crossover in the control arm was allowed, if stratification factors were employed, and the reporting of side effects was evaluated.

Results: Twelve RCTs met inclusion criteria. Four different topical steroids were used, including betamethasone 0.1%, mometasone 0.1%, hydrocortisone 1%, and beclomethasone. Eleven studies (92%) showed that topical steroids were effective in reducing incidence or delaying occurrence of grade 2 or above RD with a relative risk of 0.69 (range, 0.19 to 0.98). In all RCTs, topical steroids were consistently used from the start of radiotherapy (RT) until completion to 3 weeks post-RT. Five RCTs (42%) provided patient education on topical steroid application. Six (50%) reported on subsequent management if moist desquamation occurred. Four studies (33%) stratified potential risk factors of RD during randomization. No studies reported any long-term side effects of topical steroids.

Conclusion: Topical steroids are effective in reducing the incidence of RD. However, heterogeneity was observed among the RCTs with regard to how and when the topical steroids were applied. The long-term safety profile of topical steroids is not well studied. In the context of modern radiotherapy planning techniques and increased use of hypofractionation radiation schedules, a repeat RCT addressing these methodological concerns may provide more guidance to clinicians.