Objective: The purpose of this study was to review the initial clinical and radiologic manifestations and the follow-up of pediatric patients with Langerhans' cell histiocytosis affecting the temporal bone.
Materials and methods: We retrospectively studied 14 patients with Langerhans' cell histiocytosis affecting the temporal bone. All patients were examined initially and sequentially with CT. In six patients, MR imaging was also done.
Results: Temporal bone involvement was the initial form of presentation in 12 patients. In eight patients, temporal bone involvement presented as an isolated manifestation, and in four it was associated with multisystemic involvement. In the remaining two patients, temporal bone involvement appeared during the course of the Langerhans' cell histiocytosis. Bilateral involvement was seen in four patients. In two patients, the temporal bone was affected only at the petrous apex. CT showed destruction of bone in all 14 patients and an associated soft-tissue homogeneous mass after injection of i.v. contrast material in 12 patients. CT showed a heterogeneous appearance of the soft-tissue mass in two patients. The average period of follow-up was 5 years. In seven of the 14 patients, the disease had a satisfactory evolution in which the bony lesions of the temporal bone reossified and remodeled over the course of a year.
Conclusion: In Langerhans' cell histiocytosis, involvement of the temporal bone is usually seen on radiographs as extensive lytic lesions associated with soft-tissue masses. The lesions that remit show early disappearance of the soft-tissue mass, followed by reossification and remodeling of the involved bone. Patients with limited initial involvement of the temporal bone have a better prognosis on long-term follow-up than do patients with the multisystemic form.