[Recurrent and metastatic infantile fibrosarcoma: a case report]

Infantile fibrosarcoma is a rare malignant tumor that usually occurs during the 1st year of life. It accounts for approximately 5-10% of all sarcomas in infants younger than 1 year of age. It usually has indolent progression and metastatic spread is rare. We report the case of a patient who had infantile fibrosarcoma of the trunk. At birth, the baby presented a soft tissue mass of the scapulothoracic region. Histopathological examination after complete surgical resection at first suggested an angioma. Reanalysis of the histology after a metastatic relapse resulted in the diagnosis of infantile fibrosarcoma, which was confirmed by the presence of the specific translocation seen in infantile fibrosarcoma (ETV6/NTRK3). This patient's progression was uncommon because he developed 3 metastatic relapses. The treatment consisted of surgery, chemotherapy, and radiation therapy. The patient is alive with persistent complete remission. We discuss the diagnostic and therapeutic issues of infantile fibrosarcoma. There is a risk of erroneous diagnosis in newborn infants between benign angiomatous tumor and infantile fibrosarcoma. The fusion transcript ETV6-NTRK3 resulting from the specific chromosomal translocation t(12;15)(p13;q25) is now a useful diagnostic tool for infantile fibrosarcoma. Surgery with wide resection is the mainstay of treatment. However, infantile fibrosarcoma is a chemosensitive tumor. If initial surgery cannot be done without mutilation or is impossible, preoperative chemotherapy should be given. The role of radiation therapy is still debated.