Placental Chorangiocarcinoma: Case Report with Literature Review of a Rare Entity.

Chorangiocarcinoma is an extremely rare tumor seen in the placenta, with only six cases reported in the literature so far. Its morphological characteristics, criteria for diagnosis, and the pathophysiology remain controversial to date. Although it was predominantly considered a benign entity, a solitary case of distant metastasis has been reported in the literature. We present a case of this unusual tumor in the preterm placenta of a 29-year-old female. Grossly seen as a grey white nodule, microscopic examination revealed nests of atypical trophoblastic proliferation surrounded by vascularized stroma. No evidence of basement membrane invasion was noted. On immunohistochemistry, the trophoblastic component expressed pancytokeratin, Beta HCG, and Placental Alkaline Phosphatase with high Ki-67 labelling index. The present case highlights this exceedingly rare entity with emphasis on its morpho-immunohistochemical features along with a review of literature.