ABSTRACT

A sacrococcygeal teratoma is a neoplasm arising from the caudal end of the spine, usually protruding from the inferior end of the infant’s spinal column and displacing the anus forwards. These tumors are much more common in girls, with the female-to-male ratio being at least 3:1.1-9 The incidence is approximately one in 40 000 live births.10,11 Most authorities agree that sacrococcygeal teratoma is the result of continued multiplication of totipotent cells from Hensen’s node which fail to involute at the end of embryonic life.7,12,13 Pantoja and Rodriguez-Ibanez reviewed the conflicting theories as to the origin of these tumors.14 However, most authorities reject the concept that these are suppressed twins or parasitic fetuses, and the theory that these tumors arise from migrating germ cells travelling from yolk sac to gonad also appears to be unlikely. A familial distribution of sacrococcygeal teratoma has occasionally been reported.15-17

Willis defined the term teratoma as follows: ‘A teratoma is a true tumor or neoplasm composed of multiple tissues of kinds foreign to the part in which it arises’.13

The sacrococcygeal teratoma was second on Willis’ list of sites where teratomata are found, but in almost all pediatric surgical series, the sacrococcygeal site is the most common site listed.1-4,18 By definition, then, sacrococcygeal teratomata are composed of several types of tissue, usually derived from two or three germ layers. Robbins19 defines a teratoma as ‘a tumor composed of cells representing more than one germ layer’. In fact, however, in any tumor consisting of an epithelial component and a supporting stroma, at least two germ layers are represented. Most carcinomata, therefore, would meet Robbins’s definition of a teratoma.