In langerhans cell hystiocytosis,the characteristic abnormality seen on microscopy is:: (A) Birbecks granules, (B) Foamy macrophages, (C) Giant cells, (D) Plasma cells
Answer is A. Langerhans cell histiocytosis is characterised by the presence of Birbeck granules in the cytoplasm.(ref Robbins 9th/622)