Which of the following is a marker for Langerhans cell histiocytosis?: (A) CD 1a, (B) CD 10, (C) CD 30, (D) CD 56
Answer is A. The proliferating Langerhans cells in Langerhans cell histiocytosis are HLA-DR positive and express the CD1 antigen. Ref: Robin's Basic Pathology, 7th Edition, Page 441.