Fig. 3From: Bone pathologic fracture revealing an unusual association: coexistence of Langerhans cell histiocytosis with Rosai-Dorfman diseaseMononuclear cells stained strongly positive for CD1a, whereas giant cells with emperipolesis stained negative (black arrows) (a). Some CD1a + cells are round-shaped with oval nuclei, reminiscent to RDD-cells (“Blanks cells” or transitional cells) (b)Back to article page