The primary treatment of neonatal sacrococcygeal mature teratomas is early surgical resection with complete excision of the coccyx followed by serial serum AFP determinations to ensure the occurrence of physiological normalization of AFP levels and to facilitate early detection of tumor recurrence.[11,12] Recurrence is seen in 2% to35% of patients with neonatal sacrococcygeal mature teratoma.[13] It has been reported that almost 50% of recurrences after neonatal sacrococcygeal mature teratoma are malignant. This evidence concerns the gene AFP and neoplasm.