Myxoinflammatory Fibroblastic Soft Tissue Sarcoma with Multiple Recurrences, Case Report of Uncommon Tumor with Challenging Diagnosis and Review of the Literature

Myxoinflammatory fibroblastic soft tissue sarcomas are rare soft tissue sarcomas predominantly found in the upper extremities of middle-aged adults. Their rarity and diverse histological and anatomical presentations predispose to misdiagnosis oftentimes for more benign lesions such as ganglion cyst, giant cell tumor of the tendon sheath or tenosynovitis. This results in improper management in addition to delayed diagnosis placing patients at increased risk of worst-case scenarios including amputation, metastases or death. We are presenting the case of a 5-year-old female with myxoinflammatory fibroblastic soft tissue sarcoma of her hand initially misdiagnosed as a ganglion cyst, that recurred on two occasions after undergoing local excision. The reporting of this case aims to increase knowledge and awareness regarding the morphologic and immunohistochemical features of rare and often misdiagnosed myxoinflammatory fibroblastic soft tissue sarcomas. It is our hope that heightened awareness of this tumor will lead to inclusions as a differential diagnosis in soft tissue lesions of the extremities and thus avoid misdiagnosis and treatment.