[1] Univ Wales Hosp, Welsh Inst Dermatol, Cardiff CF4 4XW, S Glam, Wales
[2] Great Ormond St Hosp Children, Dept Paediat Dermatol, London WC1N 3JH, England
[3] Univ Wales Coll Med, Dept Pathol, Cardiff CF4 4XN, S Glam, Wales
[4] Velindre Hosp, Dept Oncol, Cardiff, S Glam, Wales