Borderline Paratesticular Serous Tumor

**Semantic type:** Neoplastic Process

**Definition:** A rare, non-invasive, serous cystic tumor that arises from the paratesticular structures. It is characterized by the presence of irregular papillary formations with irregular branching. The papillae are lined by atypical columnar epithelial cells with eosinophilic cytoplasm. Mitoses are rare. Metastases have not been reported.

**Synonyms:** - Borderline Testicular Adnexa Serous Tumor - Paratesticular Serous Tumor of Borderline Malignancy - Testicular Adnexa Serous Tumor of Borderline Malignancy