Sacrococcygeal dermoids and teratomas: historical review.

Palpable rectally, when not externally visible, sacrococcygeal teratomas have been recognized since antiquity, but their histologic segregation from other sacrococcygeal masses lagged into the twentieth century. That these tumors are potentially malignant, and that the incidence of this complication increases with age during infancy, was realized early this century, but it is only in the last two decades that the importance of (1) early surgery, (2) excision of the coccyx, and (3) a combined abdominosacral approach for lesions with retroperitoneal extension has been realized.