Pathology Haematology cdab73a7 CD marker of histiocytosis is- A CD IA B CD 1B C CD1C D CD1D High-Yield Explanation Tumour cells in histiocytosis typically express HLA -DR,S-100,and CD1a. Reference : Robbins and Cotran Pathologic basis of disease.South Asia Edition volume 1.page no. 622