Extraosseous extension of Gaucher cell deposits mimicking malignancy.

Two cases are described in which patients with type I Gaucher disease developed extraosseous soft tissue masses consisting of Gaucher cell deposits. In one instance the mass destroyed the posterior cortex of the left distal femur and protruded into the soft tissues. In the second case the lesion involved the proximal tibia and gradually extended into the soft tissues. While the incidence of neoplastic disorder such as lymphoproliferative disease appears to be more common in Gaucher disease patients than in the general population, lesions of benign etiology that mimic these aggressive processes should be considered in the differential diagnosis when cortical destruction with coexisting soft tissue most is found in these patients.