Neoplasms that contain cellular or tissue derivatives of more than one of the primary germ cell layers of the embryo that are foreign to the anatomic region in which they arise.
Gonadal teratomas occur more frequently after puberty.
Nearly always arising from the tip of the coccyx. Benign teratomas usually produce no functional impairment. The presence of bladder or bowel dysfunction suggest a malignant lesion. Evidence for venous or lymphatic obstruction or lower leg paralysis is found more commonly in malignant tumors. In addition, pressure on a meningomeylocele will often be noticeably transmitted to the anterior fontanel.