Lipomatosis

Definition

Diffuse or regional overgrowth of mature fat
- May be difficult to distinguish from multiple discrete lipomas
- May infiltrate adjacent skeletal muscle
Diffuse lipomatosis
- Diffuse overgrowth of mature fat
- Usually involves a large region of an extremity or trunk
- Age usually under 2 years
- Involves muscle and subcutaneous tissue
  - Does not involve nerves
- Recurs frequently
Encephalocraniocutaneous lipomatosis
- Haberland syndrome
- Lipomatous hamartomas of the head and face
  - Usually unilateral
- Congenital
- Cranial asymmetry and mental retardation
Neural Fibrolipoma / Fibrolipomatous hamartoma of nerve / lipomatosis of nerve is covered separately
- Surrounds and infiltrates a segment of a major nerve
Lumbosacral lipoma / lipomatosis
- Diffuse increase in mature fat over lumbosacral spine
- Spina bifida or laminar defect always present
  - Meningocele or myelocele may be present
- Usually in infants and children
- May have associated skin tags, hemangioma or hair overgrowth
Pelvic lipomatosis
- Perivesical and perirectal overgrowth
  - Rarely involves retroperitoneum and mesentery
  - Frequent cystitis glandularis
    - May develop adenocarcinoma
- Usually in black males
- Age 9-80
Symmetrical lipomatosis
- Madelung or Launois-Bensaude syndrome
- Usually neck, shoulders, upper arms
- Described as pseudoathletic or horse collar
- Frequently associated with diabetes and alcohol abuse
- More common in men of Mediterranean origin

Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342

Original posting/updates: 7/29/07, 11/16/10