[1] Oxford Univ Hosp NHS Trust, Dept Dermatol, Churchill Hosp, Oxford OX3 7LE, Oxon, England
[2] Brighton Univ Hosp, Dept Cellular Pathol, Brighton, E Sussex, England
[3] Sussex Univ Hosp, Dept Cellular Pathol, Brighton, E Sussex, England
[4] Brighton Univ Hosp, Dept Dermatol, Brighton, E Sussex, England
[5] Sussex Univ Hosp, Dept Dermatol, Brighton, E Sussex, England