Seminal Vesicle Mixed Epithelial and Stromal Tumor

**Semantic type:** Neoplastic Process

**Definition:** A rare biphasic neoplasm that arises from the seminal vesicle. It is characterized by the presence of stromal and benign epithelial components. Rarely, the stromal component may display atypia and mitotic activity and the tumor may behave in a malignant clinical course.