Sacrococcygeal teratomas (SCTs): conjoined twins or conjoined daughter?

摘要

In his critical comments Dr Drut raises objections to the epiblast or tail bud origin of sacrococcygeal teratomas (SCTs) discussed by us, and puts forward his simple conjoined twin interpretation. According to textbooks of embryology,1 conjoined twins arise by transsection of the embryoblast (inner cell mass of blastocyst) or in the epiblast and primitive streak stages of the organizer centre in the epiblast structure of the primitive node (Hensens node), which at the caudal end of the embryo is transformed into the tail bud blastema. Thus the conjoined twin interpretation preferred by Dr Drut is not incompatible with the epiblast or tail bud origin discussed by us.