placental teratoma

Definition : Teratoma of the placenta is a rare non-trophoblastic benign tumour. Placental teratomas are thought to arise from germ cells, which migrate from the dorsal wall of the yolk sac. These tumours contain elements derived from multiple germ cell layers.

Placental teratomas always lie between the amnion and the chorion, usually on the fetal surface of the placenta, but sometimes, within the membranes.

The origin of placental teratoma is obscure. Placental teratomas originate from the abnormal migration of embryonic germ cells. These cells migrate through the umbilical cord before arriving in the placenta.

Differential diagnosis

 acardiac fetus amorphous

• The differential diagnosis of placental teratoma is a fetus amorphous, which is a blighted fetus arising from a multiple pregnancy.
• The distinguishing feature in fetus amorphous is the presence of some growth organization with central skeletal development, and with partial or complete formation of a vertebral column.
• Second differentiating feature is a separate, poorly developed umbilical cord which is either attached to the placenta or to its twin, or to a separate placenta.

See also

 placental anomalies

• placental tumors

 teratoma

Open references

 https://www.hindawi.com/journals/criog/2012/857230/
 https://www.annsaudimed.net/doi/10.5144/0256-4947.1999.359