Primary Parotid Tumor Thrombosis: Immunohistologic Features and Awareness of Metastatic Potential
American Journal of Dermatopathology
Introduction: Tumor thrombosis is a poor prognostic feature and is exceptionally rare in salivary gland malignancies.
Methods: We identified a case of primary parotid epithelial-myoepithelial carcinoma (EMC) with tumor thrombosis.
Results: An 82-year old male presented with a complaint of a right facial mass. Imaging demonstrated a mass of the right parotid gland with attenuation of the right external jugular vein (EJV). The patient underwent right parotidectomy and selective neck dissection. Tumor thrombosis was found intraoperatively within the EJV. Final pathology demonstrated a poorly differentiated EMC. The tumor was positive for CK5/6, p16, p40, SOX10, smooth muscle actin, myosin, and synaptophysin, but negative for INSM1, NUT, S100, ERG, and uroplakin. Adjuvant radiation therapy was administered. Three months later, imaging revealed numerous bilateral pulmonary nodules with biopsy demonstrating poorly differentiated EMC without locoregional relapse.
Conclusions: Primary parotid tumor thrombosis is rare and carries a poor prognosis. The use of early systemic therapy should be investigated.
Dekhou A, Rehman R, Parzen J, Quinn T, Deraniyagala R. Primary parotid tumor thrombosis: Immunohistologic features and awareness of metastatic potential. American Journal of Dermatopathology: 2021 August; 43(Supplement): p. 1-14.