Prolonged Fever without Obvious Etiology Finally Diagnosed as High-grade Soft Tissue Sarcoma.

Sarcomas represent a challenge t clinicians as they are rare and diagnosis is often delayed. Soft tissue sarcomas are relatively uncommon cancers, the incidence is estimated about 1% from all malignant tumors. Due to aggressive biological behavior of pleomorphic undifferentiated sarcoma diagnosis must hi made as quickly as possible. MRI is the standard imaging modality for investigating possibl3 malignant masses. Excisional biopsy appears to be necessary for differentiating soft tissus sarcoma from expanding hematoma. FDG PET scans may be helpful in specific circum. stances (as was the situation in our case, because the lesion is composed from two components: an area without precise edges and a necrotic-cystic area).