Nuchal-type Fibroma
Differential Diagnosis
- Gardner associated fibroma
- Fibrolipoma
- Elastofibroma
- Desmoid fibromatosis
- Solitary fibrous tumor
- Spindle cell lipoma
- Scar
- Fibrous hamartoma of infancy
| Gardner Associated Fibroma | Nuchal-type Fibroma |
|---|---|
| Age range 2 mo to 36 years | Age range 3 to 74 years |
| Most, but not all cases, extranuchal | 70% nuchal |
| Formless sheets of collagen | Thick bundles of collagen |
| Rare entrapped nerves | Frequent entrapped traumatic neuroma areas |
| Nuchal-type Fibroma | Fibrolipoma |
|---|---|
| Radiates into fat | Encapsulated |
| Abundant collagen | Focal collagen |
| Frequent entrapped nerves | Lacks entrapped nerves |
| Nuchal-type Fibroma | Elastofibroma |
|---|---|
| Elastic fibers not prominent | Prominent abnormal elastic fibers |
| Subcutaneous component in all cases | Deep, subscapsular |
| Nuchal-type Fibroma | Extra-abdominal Desmoid Fibromatosis |
|---|---|
| Involves superficial tissues | Involves deep tissues |
| Infrequently involves skeletal muscle | Involves skeletal muscle |
| Paucicellular | May have cellular areas |
| Nuchal-type Fibroma | Solitary Fibrous Tumor |
|---|---|
| Paucicellular | May have cellular areas |
| Radiates into fat | Usually circumscribed |
| Inconspicuous vessels | Frequent stag horn vessels |
| Nuchal-type Fibroma | Spindle Cell Lipoma |
|---|---|
| Radiates into fat | Encapsulated |
| Abundant collagen | Focal collagen |
| Frequent entrapped nerves | Lacks entrapped nerves |
| Nuchal-type Fibroma | Scar |
|---|---|
| No history of trauma | History of trauma |
| Nuchal-type Fibroma | Fibrous Hamartoma of Infancy |
|---|---|
| Lacks triphasic pattern, no immature component | Triphasic lesion with spindle cell fibrous areas, adipose tissue and clusters of immature mesenchymal cells |
| Most age 20 to 40, unless associated with Gardner syndrome | Age range congenital to 4 years |
| Typically located in or near posterior neck | Usually axillary or inguinal |
