Type I Gaucher disease: extraosseous extension of skeletal disease

Objective. To investigate the frequency and morphology of extraosseous exte nsion in patients with Gaucher disease type I. Design and patients. MRI examinations of the lower extremities were analyze d in 70 patients with Gaucher disease type I. Additionally, the thoracic sp ine and the midface were investigated on MRI in two patients. Results. Four cases are presented in which patients with Gaucher disease ty pe I and severe skeletal involvement developed destruction or protrusion of the cortex with extraosseous extension into soft tissues. In one patient, Gaucher cell deposits destroyed the cortex of the mandible and extended int o the masseter muscle. In the second patient, multiple paravertebral masses with localized destruction of the cortex were apparent in the thoracic spi ne. In the third and fourth patient, cortical destruction with extraosseous tissue extending into soft tissues was seen in the lower limbs. Conclusions. Extraosseous extension is a rare manifestation of Gaucher bone disease. While an increased risk of cancer, especially hematopoietic in or igin, is known in patients with Gaucher disease, these extraosseous benign manifestations that may mimic malignant processes should be considered in t he differential diagnosis of extraosseous extension into soft tissues. A na rrow neck of tissue was apparent in all cases connecting bone and extraosse ous extensions.