This chapter covers fibrous, fibrohistiocytic, and myofibroblastic tumors that have metastatic potential. Congenital/infantile fibrosarcoma is the exception to that rule, as it behaves less aggressively than its adult counterpart. Adult-type fibrosarcoma is a diagnosis in decline due to the recognition of distinct variants: low-grade fibromyxoid sarcoma, sclerosing epithelioid fibrosarcoma,
... [Show full abstract] myxofibrosarcoma, low-grade myofibroblastic sarcoma (myofibrosarcoma), and myxoinflammatory fibroblastic sarcoma. Undifferentiated pleomorphic sarcoma may also present as a superficial tumor and will be briefly discussed. The chapter closes with a discussion of undifferentiated pleomorphic sarcomas of the skin, specifically atypical fibroxanthoma and pleomorphic dermal sarcoma.