Three cases of Langerhans' cell histiocytosis (histiocytosis X) are re
ported in which the clinical presentations were (1) soft-tissue enlarg
ements, (2) oral ulcerations, and (3) leukoplakia. Each case was witho
ut bone involvement at the time of diagnosis, and two patients were ol
der than 60 years of age. Definitive diagnoses were aided with the use
of immunohistochemistry.