Infantile fibrosarcoma.

The pathologic features and the behavior of 53 cases of infantile fibrosarcoma are presented. The tumor nearly always occurred during the first 2 years of life; 41 of the 53 cases occurred during the first, six during the second, and three each during the third and fourth year of life, respectively. Twenty of the 53 cases were present at birth. The tumor was more common in boys (60%) and affected chiefly the distal portions of the lower and upper extremities (72%). Most of the tumors grew rapidly and reached a large size within a few weeks or months. They were generally poorly circumscribed and infiltrated variously subcutaneous fat, muscle, fascia and tendons. Microscopically, they were composed of immature-appearing spindle-shaped cells and were marked by their high cellularity and prominent mitotic activity. Despite these features, follow-up information revealed a favorable clinical course, particularly as compared with the adult form of fibrosarcoma. Of the 48 patients with follow-up data, 31 were alive and well with no evidence of recurrence, eight were alive with recurrence, and one was alive following lobectomy for metastatic tumor. Of the living patients, 12 were treated with amputation, nine with radical or wide local excision, and 15 with simple excision. In two cases surgery was followed by chemotherapy, and in one, by radiotherapy. Eight of the 48 patients with follow-up had died, four of metastatic tumor (8.3%) and four of miscellaneous causes. Wide local excision appears to be the treatment of choice unless the size of the tumor and its anatomic location require amputation. Since late recurrent and metastatic lesions were encountered, long-term followup is necessary before one can safely assume that the patient has been cured.