Placental Site Trophoblastic Tumor
Placental Site Trophoblastic Tumor: The intermediate trophoblastic cells are discohesive and arranged singly or in small clusters. Some areas may show sheet-like arrangement. The tumor cells have large, irregular hyperchromatic nuclei and abundant eosinophilic cytoplasm. Multinucleated forms and intranuclear pseudoinclusions are also seen. Infiltration of vascular walls is common. The tumor cells stain positively for human placental lactogen but are p63-negative. The prognosis is considered to be better than choriocarcinomas.