Extranodal Natural Killer/T-Cell Lymphoma of the Placenta: A CaseReport of a Previously Undescribed Entity and Review of the Literature.

There have been only eight cases of non-Hodgkin’s lymphoma with placental involvement published in the literature. Our case is the first case of NK/T-Cell lymphoma involving the placenta. NK and T-cells share a common ontogeny and both express T lineage antigens such as CD2 and CD7, but NK-cells lack surface CD3 and express cytoplasmic CD3 as well as CD16, CD56 and CD57. NK/T-cell lymphoma cells are infected with EBV and positive in-situ hybridization is considered a diagnostic requisite. High plasma EBV DNA is correlated negatively with survival and serial EBV plasma DNA monitoring is useful for assessing therapeutic response and detecting recurrence. There does not appear to be a clear relationship between placental involvement with systemic non-Hodgkin’s lymphoma, nor a direct relationship of transplacental transmission if placental tissue is infiltrated with malignant cells.