Langerhans-cell histiocytosis (LCH) is a reactive proliferative disease characterized by the accumulation of abnormal histiocytes. The disease is broadly divided into two groups, unisystem and multisystem disease. The aetiology of LCH is unknown; the disease is currently accepted to be a reactive process rather than a malignancy. Localized LCH of bone is a benign tumour-like condition, which is characterized by a clonal proliferation of Langerhan’s-type histocytes, which infiltrate bone and cause osteolytic lesions. The common bones involved include – skull, pelvis, and diaphysis of long bones.

We wanted to determine whether patient demographics at the time of presentation could help determine the clinical course and eventual outcome of the disease. We prospectively reviewed 68 patients with a primary diagnosis of LCH.

Forty-six patients had unisystem disease, 22 had multisystem disease. There was a statistically significant difference in the age of presentation between the two groups. There were 6 deaths, all had multisystem disease. Of the 46 patients with unisystem disease, 31 (67.3%) underwent orthopaedic surgical intervention, 26 open biopsies and 5 curettage and bone grafting of lesions of the humeras (2), skin, clavicle and skull (1 each). There was a statistically significant difference in the average length of follow-up, between the 2 groups.

We recommend closed and prolonged multidisciplinary follow-up of patient initially presenting with multisystem disease. Patients with unisystem disease can safely be discharged after a short follow-up period.