Soft Tissue Giant Cell Tumor of Low Malignant Potential
Differential Diagnosis
- Giant cell malignant fibrous histiocytoma
- Tenosynovial giant cell tumor
- Plexiform Fibrohistiocytic Tumor
- Extraskeletal osteosarcoma
- Nodular Fasciitis
- Giant cells may be seen in leiomyosarcoma, epithelioid sarcoma and other sarcomas, carcinomas and melanomas
- These can be distinguished by recognizing areas of the tumor with the classic appearance or immunophenotype of the other neoplasm
| Giant Cell Malignant Fibrous Histiocytoma | Soft Tissue Giant Cell Tumor of Low Malignant Potential |
|---|---|
| Marked cytologic atypia in mononuclear cell component | Mild atypia at most |
| Coagulative tumor cell necrosis frequently present | Coagulative necrosis not permitted |
| Atypical mitotic figures frequently found | Atypical mitotic figures not permitted |
| Tenosynovial Giant Cell Tumor | Soft Tissue Giant Cell Tumor of Low Malignant Potential |
|---|---|
| Usually located near joints | Wide variety of locations |
| Usually low mitotic rate | Frequently high mitotic rate |
| Usually polymorphous with siderophages, foam cells and lymphocytes | Usually lacks siderophages, foam cells and lymphocytes |
| Metaplastic bone not seen | Metaplastic bone frequent |
| Usually has hyalinization of stroma | Lacks hyaline stroma |
| Soft Tissue Giant Cell Tumor of Low Malignant Potential | Plexifiorm Fibrohistiocytic Tumor |
|---|---|
| Mixed giant and spindled cells but not distinctly biphasic | Biphasic with nodules of histiocyte-like cells with giant cells and spindled fibroblastic areas |
| Infiltrating nodules | Plexiform infiltrative pattern |
| Frequent mitotic figures | Mitotic figures rare |
| Extraskeletal Osteosarcoma | Soft Tissue Giant Cell Tumor of Low Malignant Potential |
|---|---|
| Malignant cytologic features | Mild atypia at most |
| Osteoid in a lace-like pattern formed by malignant cells | Frequently a rim of metaplastic bone |
| Giant Cell Rich Nodular Fasciitis | Soft Tissue Giant Cell Tumor of Low Malignant Potential |
|---|---|
| Areas of typical nodular fasciitis usually present with loose myxoid stroma and C and S shaped fascicles | Lacks areas with appearance of nodular fasciitis |
| Giant cells frequent in intravascular fasciitis | Vascular invasion is frequent but main lesion is not intravascular |
