A MANDIBULAR NEUROENDOCRINE TUMOR, POORLY DIFFERENTIATED

Neuroendocrine tumors constitute a heterogeneous group of lesions, which are extremely rare in the oral cavity. A 70-year-old male patient reported a chief complaint of a swelling in the mouth. Intraoral examination revealed a nodule in the anterior region of the right jaw over the alveolar ridge of approximately 3 × 2.5 cm. Computed tomography demonstrated a hypodense destructive lesion. An incisional biopsy was done and the histopathologic findings described a poorly differentiated malignant neoplasm without neural invasion. Immunohistochemical analysis was requested and the results showed positivity for the antibodies CD10, SYN, chomogranin, with a strong staining for Ki67, and focal staining for vimentin. The CK20, cytokeratin AE1/AE3, PSA, and CK7 antibodies were negative. The patient was referred to an oncology hospital. Immunohistochemistry is a highly sensitive method for the diagnosis of neuroendocrine tumors. A mix of surgery, multidrug chemotherapy, and radiotherapy are used for treatment.