Primary Small Cell Neuroendocrine Carcinoma of the Tonsil: A Rare Case Report and Review of Literature

Abstract

Neuroendocrine tumors of the head and neck region are extremely infrequent. Small cell neuroendocrine carcinoma (NEC) of the tonsil is almost unheard of and carries a poor prognosis. There is no standard treatment protocol with regard to this tumor type. We present a 74-year-old male with complaints of odynophagia and swelling on the right side of the neck for one month. Physical examination showed a right neck level II lymph node with an ulceroproliferative mass involving the (R) tonsillar fossa, uvula, soft palate, and obstructing the oropharynx. MRI showed a right tonsillar mass measuring 3.4 × 3.3 × 1.4 cm with an ipsilateral level II lymph node measuring 2.7 × 1.9 cm. PET-CT scan showed a metabolically active right tonsillar lesion with a right level II lymph node. Histopathological examination revealed small cell NEC. On immunohistochemistry, tumor cells were strongly positive for PanCK, synaptophysin, chromogranin, CD56, and p16. Tumor cells were negative for CD45, CK7, CK20, and EBV-LMP. Ki-67 was 80%. The patient was treated with cisplatin and etoposide-based chemotherapy, and the tumor showed a very good response.