Complete resection is curative in the majority of patients with infantile fibrosarcoma. However the large size of the lesion frequently makes resection without major functional consequences impossible (for instance, tumors of the extremities often require amputation for complete excision). Preoperative chemotherapy has made a more conservative surgical approach possible; agents active in this setting include vincristine, dactinomycin, cyclophosphamide, and ifosfamide.[30,31,32]; [Level of evidence: 3iiA]; [Level of evidence: 3iiB]
These tumors lack the translocation seen in infantile fibrosarcomas. They present like the great majority of nonrhabdomyosarcomas and the management approach is similar.
Dermatofibrosarcoma is a rare tumor, but many of the reported cases arise in children. The tumor has a consistent chromosomal translocation t(17;22)(q22;q13) that juxtaposes the COL1A1 gene with the PDGF-beta gene.
Most dermatofibrosarcoma tumors can be cured by complete surgical resection. Wide excision with negative margins or Mohs or modified Mohs surgery will prevent most tumors from recurring.
In retrospective reviews, adjuvant radiation therapy after incomplete excision may have decreased the likelihood of recurrence.[37,38]
When surgical resection cannot be accomplished or the tumor is recurrent, treatment with imatinib has been effective.[39,40,41]
Guidelines for workup and management of dermatofibrosarcoma protuberans have been published.
Inflammatory myofibroblastic tumor
Inflammatory myofibroblastic tumor is an incompletely characterized neoplasm of intermediate biologic potential. It recurs frequently but metastasizes rarely.[43,44] Roughly half of inflammatory myofibroblastic tumors exhibit a clonal mutation that activates the anaplastic lymphoma kinase (ALK)-receptor tyrosine kinase gene at chromosome 2p23.
There are no well-documented responses to chemotherapy. A case report described a partial response in a patient with recurrent inflammatory myofibroblastic tumor who was treated with crizotinib, an ATP-competitive inhibitor of the ALK and MET tyrosine kinases. There are case reports of response to either steroids or NSAIDs.[47,48]
Low-grade fibromyxoid sarcoma
Low-grade fibromyxoid sarcoma is somewhat misnamed, because its appearance is deceptively benign, but its behavior is malignant, although rather indolent. In a review, 21 of 33 patients had local recurrences after intervals of up to 15 years (median, 3.5 years) and 15 had metastases, mostly in the lungs and pleura, after periods of up to 45 years (median, 5 years), indicating that follow-up must be lifelong. Even after metastases occur, the course may be indolent.
The limited treatment information for low-grade fibromyxoid sarcoma is summarized in the review above. This tumor is not very chemosensitive and there are little data regarding the use of chemotherapy and/or radiation therapy.
Myxofibrosarcoma, low grade
Myxofibrosarcoma, low grade, is a rare lesion, especially in childhood. It is typically treated with complete surgical resection.