Dedifferentiated Liposarcoma
Clinical
- Age: Most 50-70 years, all over 21 years old
- Site of involvement
- Same as atypical lipomatous tumor
- Central body
- Retroperitoneum, spermatic cord, mediastinum
- Frequent recurrences, may be uncontrollable
- Initial specimen or recurrences may exhibit dedifferentiation
- Intramuscular / intermuscular
- Thigh, arm, buttock
- Frequent recurrences, rarely uncontrollable
- Dedifferentiation rare
- Subcutaneous
- By definition does not occur in posterior neck, upper back or shoulders
- Infrequent recurrences, never uncontrollable
- Dedifferentiation very rare
- Viscera
- Larynx most common, other sites extremely rare
- Recurrences frequent, never uncontrollable
- Dedifferentiation very rare
- Prognosis
- Recurrence rate 40-50%
- Metastatic rate 15-20%
- Only dedifferentiated component can metastasize
- Most common sites for metastases are lung, liver, bone
- Median survival approximately 5 years from appearance of dedifferentiated component
- Prognosis may be better than for patients with corrresponding pure high grade sarcoma in cases outside retroperitoneum and inguinal area
