Intra-operative cytodiagnosis of primary ovarian choriocarcinoma with Ki67 immunoexpression.

Primary ovarian choriocarcinoma is a rare neoplasm that can be gestational and non-gestational in origin. It accounts for one in 369 million pregnancies. Both types present with similar clinical, histomorphological and ultrastructural findings. But, it is essential to differentiate the two because the gestational type has a better clinical course and responds to single-agent chemotherapy. Usually, the gestational ovarian choriocarcinoma is metastatic from uterine choriocarcinoma and follows antecedent pregnancy and is seen in females of 40 years or older. DNA polymorphism analysis showing the presence of paternal genes in the tumor establishes the gestational origin of choriocarcinoma. We present the intra-operative cytological findings of a case of primary ovarian choriocarcinoma in a 25-year-old lady arising from ectopic pregnancy with Ki67 immunostain.