A reactive fibrohistiocytic lesion simulating fibrous histiocytoma has been reported by Snover et al.[16] Reactive granular cells in sites of trauma have been regarded of histiocytic nature.[17] Sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease) might share several aspects of the XP. Likewise there might be some superimpositions between the XP and the plasma cell granuloma/histiocytoma-inflammatory myofibroblastic tumor complex.[18][19] The XP might be an important stage of this complex.