Undifferentiated sarcoma of the soft tissues with cystic degeneration: Case report and review of literature

ABSTRACT

Undifferentiated sarcoma (UNDS) of the soft tissue is an exceedingly rare disease. Its diagnosis depends mainly on molecular and immunohistochemical analyses to exclude other soft-tissue sarcomas. It is difficult to confirm a positive diagnosis by imaging pathological features because of their rarity and similarity with other conditions. Since 2013, only 13 cases of undifferentiated soft-tissue sarcoma, mostly diagnosed through imaging of solid tumors in infant and children, have been reported. The authors present a rare case of a 3-month-old Chinese boy with UNDS primarily in the left lower extremity and characterized by a cystic and solid growth pattern