A teratoma-like lesion of the placenta: a case report.

Teratoma-like lesions of the placenta are rare and of disputed histogenesis. We describe one such tumour arising in the placenta of a normal full-term male infant delivered to a 33-yr-old woman. This lesion and all previously reported cases appear histologically and clinically benign. The authors favour the viewpoint that the so-called placental teratoma represents an extreme form of fetus amorphus.