Melanotic neuroectodermal tumor of infancy: its histological similarities to fetal pineal gland.

Striking similarities between the pineals of 107 fetuses and infants and a pigmented neuroectodermal tumor occurring in the right orbital and right frontal regions in a 6-month-old Puerto Rican boy were found. Both the human fetal pineal and melanotic neuroectodermal tumors of infancy are characterized by pigmented (melanin) epithelial cells, small undifferentiated cells, and a fibrovascular stroma. Our findings suggest the fetal pineal may be a normally occurring precursor of the melanotic neuroectodermal tumor of infancy, or that melanin production may be a normal capability of differentiating neuroepithelial cells.