Langerhans cell histiocytosis of bone in children and adolescents.

The purpose of this paper was to analyze the orthopaedic aspects of Langerhans cell histiocytosis and to assess the outcome after treatment. Fifty-six patients with Langerhans cell histiocytosis involving the bone were retrospectively studied. Three groups were identified with regard to the type of bone involvement. Group I patients (n = 26) had a solitary bone lesion, with no systemic involvement. No treatment was given in 22 patients and curettage was done in 4 patients. At last follow-up, complete or partial healing was observed in 25 patients. Group II patients (n = 13) had multiple bone lesions, with no systemic involvement. Clinical and radiographic pictures as well as the outcome after treatment were similar to those in group I. Group III patients (n = 17) had bone and systemic involvement. Chemotherapy was used in all group III patients, with adjuvant radiotherapy in seven patients. Recurrence or new lesions were observed in 11 patients. Complications of treatment were observed in 14 patients. Lesions in group I and II patients had a considerable potential for spontaneous healing. Group III patients had the worst prognosis. Current chemotherapy protocols have a high morbidity and produce a variable response.