Boer J, et al. - This study sought to evaluate the long-term efficacy of radiotherapy (RT) in early-stage hidradenitis suppurativa (HS). Researchers conducted a postal survey-based long-term follow-up with simple factual questions of partly retrospective and partly contemporary characteristics. In this study, 64 individuals (96 axillae), diagnosed with mild to moderate HS were irradiated with an orthovoltage unit with 100 kV, 3 mm Al or 200 kV, 0.5 Cu filtering, respectively. This study’s findings demonstrate that RT seems to be an effective treatment for early and mild HS in the majority of patients. No side effects were reported after a median follow-up period of 40 years in this case series.