Infantile Fibrosarcoma Histologically Mimicking a Benign Soft-Tissue Tumor

Infantile fibrosarcoma is a rare soft-tissue neoplasm, which may render a diagnostic challenge leading to misdiagnosis and consequently an inappropriate treatment of patients. This study reports a case of infantile fibrosarcoma that mimicked a hemangioma in an 11-month-old girl. As the lesion signal in the MRI was not consistent with the diagnosis of hemangiomas, we performed a core needle biopsy, which its result was consistent with the diagnosis of infantile fibrosarcoma. The lesion was initially treated with surgical resection. However, the lesion recurred one year after the surgery. The recurrence was managed with debulking surgery. The fifth finger was necrotized during the hospitalization after the relapse surgery. Finally, the necrotic finger was amputated. Also, adjuvant chemotherapy was used to prevent further relapses. The 1-year follow-up of the patient was recurrence-free. These findings highlight the importance of considering infantile fibrosarcoma when an infant presents with a lesion that clinically mimics a vascular lesion.