Figure 5.

Representative sections of Langerhans cell histiocytosis. (a) Low-power (20x) image demonstrates a diffusive cellular infiltrate with prominent eosinophils. (b) High-power (100x) image demonstrates populations of eosinophils, macrophages with foamy cytoplasm, and large, variably elongated spindled cells with indented, grooved nuclei and eosinophilic granular cytoplasm. These cells are diffusely positive for (d) S100 and (e) CD1a and (c) focally positive for CD68, consistent with Langerhans cells.