A Comparative Study of Clinicopathological and Immunohistochemical Expression of CD1a, RANK and RANKL in Langerhans Cell Histiocytosis of Jaw and Skull Lesions


Background: Langerhans' cell histiocytosis (LCH) is a group of conditions affecting the reticuloendothelial system. Itincludes Letterer-Siwe disease, Hand-Schuller-Christian disease and eosinophilic granuloma and most often presentsin childhood.Materials and methods: Twenty-five cases of LCH were diagnosed histologically and confirmed by CD1a antibodyand assessed immunohistochemically using anti-RANKL and anti-RANK antibodies to evaluate osteoclastogenicmechanism.Results: Regarding jaw cases, there was a significant correlation between CD1a and RANK (P=0.016). While in theskull, highly significant correlation existed between RANK and RANKL (p=0.001). Among the sites, there was nostatistically significant difference found for each the immunohistochemical markers used.Conclusion: LCH of jaws and skull bear similar osteoclastogenic mechanism when quantified with RANK and RANKLimmunostaining respectively. With a significant correlation between CD1a and RANK for jaw cases, while in the skulllesions, there was a high significant correlation between RANK and RANKL.