Lipoblastoma / Lipoblastomatosis
Differential Diagnosis
| Lipoma |
Lipoblastoma / Lipoblastomatosis |
| Lacks primitive mesenchymal cells and lipoblasts |
Primitive mesenchymal cells and lipoblasts virtually always at least focally present |
| Unusual on extremities |
Frequent on extremities |
| Various chromosomal abnormalites but not involving 18q11-13 |
18q11-13 abnormalities |
Occasional lobules of lipoblastomatosis may be virtually indistinguishable
| Myxoid Liposarcoma |
Lipoblastoma / Lipoblastomatosis |
| Maturation if present, occurs towards periphery |
Maturation if present, occurs towards center of lobules |
| Rare <20, very rare <10 |
Very rare >20, rare >10 |
| May have hypercellular areas |
Uniformly hypocellular |
| Virtually always deep |
May be superficial or deep |
| t(12;16) or t(12;22) |
Abnormalities involving 8q(11-13) |
| Lipoblastoma |
Hibernoma |
| Restricted to children at presentation |
Rare in children |
| Immature cells and lipoblasts |
Microvesicular brown fat |
| 18q11-13 abnormalities |
11q13 abnormalities |
| Lipoblastoma |
Chondroid Lipoma |
| Uniform population of lipoblasts |
Variable size of vacuolated cells |
| No chondroid matrix |
Chondroid matrix |
| Restricted to children |
Age range 14-75 |
| Deletions of 8q(11-13) |
t(11;16) |
| Lipoblastoma |
Fat Necrosis |
| At least focal vascular myxoid stroma |
Lacks vascular myxoid stroma |
| Immature fat cells with vacuoles |
Foamy cytoplasm, few vacuoles |
| Uniform pattern |
Variable pattern from normal fat to necrotic fat to histiocytes |
