part of extravillous cytotrophoblast extravillous cytotrophoblast cell 2018-09-25T11:17:05Z BTO:0006207 BrendaTissueOBO Extravillous cytotrophoblast cells are the cells of the outermost layer of the fetal component of the human placenta. The extravillous cytotrophoblast cells located proximal to the villous stroma are proliferating cells. Marion extravillus cytotrophoblast cell