Lipofibromatosis
Definition
- Pediatric neoplasm composed of fat with a septal fibroblastic component
Diagnostic Criteria
- Age range birth to 12 years
- Predominantly fatty tissue
- Mature fat
- Occasional small collections of univacuolated cells
- At interface of fibroblastic and fat components
- Vacuoles do not indent nucleus as in lipoblasts
- Fascicles of fibroblastic cells
- Predominantly in septa of fat
- Collagen generally scant to moderate
- Occasionally myxoid
- Lack primitive myxoid mesenchymal nodules
- No significant atypia or pleomorphism
- Mitotic figures infrequent
- Poorly defined margin
- Frequently involves and entraps vessels, nerves, muscle, skin adnexa
- Scattered pigmented spindled / dendritic cells in 2/45 cases
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
Original posting : July 29, 2007