Summary Background Graft-versus-host disease (GVHD) represents an important complication following allogeneic bone marrow transplantation. In recent years, narrowband ultraviolet B (NB-UVB, 311–313 nm) has been found to be a beneficial adjuvant treatment in patients refractory to first-line immunosuppressive drugs. Objectives The aim of this study is to analyse retrospectively the clinical outcome of 10 GVHD paediatric patients treated with NB-UVB therapy. Patients and methods Ten paediatric patients (six girls and four boys: median age 12·5 years, range 4–20) with cutaneous GVHD were enrolled in the study: five patients with chronic GVHD and five patients with an overlap syndrome GVHD. All patients had already been shown to be resistant to first-choice immunosuppressive protocols, and were treated with NB-UVB phototherapy until a clinical remission of skin lesions occurred. Results A complete response (absence of lesions) was achieved in 80% of the cases (eight patients) after a median number of 29 treatments, corresponding to a median of 7·5 weeks (52 days) of treatment (range 3–13 weeks), with an average cumulative dose of 28·71 J cm−2 (range 1·02–70·38 J cm−2). Only two patients reported a partial remission (
