Primary Neuroendocrine Carcinoma of the Palate: A Case Report

Abstract

Primary neuroendocrine carcinomas (NECs) of the oral cavity represent exceptionally rare malignancies (< 30 reported cases globally), posing significant diagnostic challenges due to histological mimicry of other round cell tumors and nonspecific clinical presentation. This report details a novel case with atypical clinicopathological features and favorable therapeutic outcomes. A 38-year-old male presented with a 3-month history of a right hard palate ulceration. Clinical examination revealed an indurated endophytic lesion. Histopathology and immunohistochemistry confirmed poorly differentiated large cell NEC. Due to unresectable pterygopalatine fossa involvement, chemoradiation was administered. Given the extreme rarity of oral large cell neuroendocrine carcinoma (LCNEC), clinicians must consider this entity even in patients lacking traditional risk factors (e.g., smoking). Its aggressive growth pattern and metastatic propensity necessitate prompt specialist referral for early intervention. © 2025 Tehran University of Medical Sciences.