myxofibrosarcoma
Myxofibrosarcoma is a malignant soft tissue tumor. It is classified as a type of a fibroblastic/myofibroblastic tumor.
Terminology
Previously known as a myxoid variant of malignant fibrous histiocytoma .
Epidemiology
Typically presents in older patients (6 decade) . There may be male predilection. Although rare in general, it is considered the most common soft tissue tumor to present in late adult life.
Clinical presentation
Patients often present with a painless enlarging soft tissue mass in the extremities.
Pathology
Location
Tends to favor the dermal and subcutaneous tissues than deeper soft tissues :
- lower limbs (~77%)
- trunk (~12%)
- retroperitoneum/mediastinum (~8%)
- head and neck (3-10%)
Histology
In contrast to most other histologic types of low-grade soft-tissue sarcoma, recurrent low-grade myxofibrosarcomas are often infiltrative; shows tapering, have tail-like margins with superficial spreading configuration and can even metastasize to various distant sites .
Radiographic features
MRI
Myxofibrosarcoma often shows abnormal signal infiltration along the fascial plane on MRI .
Signal characteristics
- T1: the myxoid component is often of low signal
- T2/STIR: the myxoid component is high signal
- T1 C+ (Gd): the myxoid component tends not to enhance while the remaining soft tissue component enhances
Treatment and prognosis
Prognosis will somewhat depend on grade .