Congenital infantile fibrosarcoma: a clinical mimicker of hemangioma

Area of Science:

• Pediatric Oncology
• Surgical Pathology
• Soft Tissue Tumors

Background:

• Congenital infantile fibrosarcoma (CIFS) is a rare, often congenital, soft tissue neoplasm in infants.
• CIFS typically presents as a rapidly growing mass, frequently in the extremities.
• While generally having a better prognosis than other pediatric sarcomas, early and accurate diagnosis is crucial.

Observation:

• A case of CIFS in an infant presenting as a nonspecific, ulcerated mass over the right shoulder.
• The lesion was initially suspected to be a benign vascular tumor, such as a hemangioma, due to its highly vascular appearance.
• The clinical presentation mimicked other common pediatric skin lesions, delaying definitive diagnosis.

Findings:

• Histopathological examination revealed a highly cellular tumor composed of densely packed spindle cells arranged in fascicles.
• Immunohistochemical analysis demonstrated that the tumor cells were positive for vimentin, a common marker for mesenchymal tumors.
• These findings confirmed the diagnosis of congenital infantile fibrosarcoma.

Implications:

• This case underscores the importance of considering CIFS in the differential diagnosis of pediatric soft tissue masses, even with atypical presentations.
• Accurate histopathological and immunohistochemical evaluation is essential for differentiating CIFS from benign vascular lesions and other sarcomas.
• Timely diagnosis and appropriate management can lead to favorable outcomes for patients with CIFS.