Leuco-erythroblastic reaction can be the bone marrow response to any irritation, including infiltration by any malignancy (or histiocytosis for that matter), but special stains for histiocytes need to be done in the marrow to prove the diagnosis. Click here for the Bone marrow Slide of Leuco-eythroblastic marrow
Click here for Complete Discussion on Langerhans cell Histiocytosis | 
