A novel mechanism of transplacental cancer transmission: natural killer/T-cell lymphoma in the paratesticular region is of maternal origin

To the editor: The placental syncytiotrophoblast layer is a barrier that protects the fetus from infection and cancer metastasis. Even if mother-derived cells enter the fetus, they are usually rejected and cannot be engrafted. Materno-fetal transmission of leukemia/lymphoma is therefore extremely