[1] Leiden Univ Ctr, Med Ctr, Dept Dermatol, NL-2300 RC Leiden, Netherlands
[2] NCI, Pathol Lab, NIH, Bethesda, MD 20892 USA
[3] Univ Zurich Hosp, Dept Dermatol, CH-8091 Zurich, Switzerland
[4] Graz Univ, Dept Dermatol, Graz, Austria
[5] Univ Milan Biococca, Dept Dermatol, Milan, Italy
[6] Osped Maggiore, Milan, Italy
[7] Univ Pittsburgh, Sch Med, Dept Pathol, Div Hematopahtol, Pittsburgh, PA USA
[8] Univ Copenhagen, Dept Pathol, Copenhagen, Denmark
[9] Univ Rome, Dept Dermatol, Rome, Italy
[10] Cruces Hosp, Dept Dermatol, Bilbao, Spain
[11] Massachusetts Gen Hosp, Dept Pathol, Boston, MA 02114 USA
[12] Harvard Univ, Sch Med, Boston, MA USA
[13] Hop Louis Pasteur, Dept Dermatol, Colmar, France
[14] Univ Zurich Hosp, Dept Pathol, CH-8091 Zurich, Switzerland
[15] Univ Vienna, Dept Dermatol, Vienna, Austria
[16] Univ Florence, Dept Dermatol Sci, Florence, Italy
[17] Allgemeines Krankenhaus St Georg, Dept Dermatol, Hamburg, Germany
[18] Univ Florence, Dept Human Pathol & Oncol, I-50121 Florence, Italy
[19] Humboldt Univ, Dept Dermatol, Berlin, Germany
[20] Hop Henri Mondor, Dept Pathol, F-94010 Creteil, France
[21] St Thomas Hosp, St Johns Inst Dermatol, Skin Tumour Unit, London, England
[22] Vrije Univ Amsterdam, Med Ctr, Dept Pathol, Amsterdam, Netherlands