A rare case of metastases to the maxillary sinus from sigmoid colon adenocarcinoma.

Metastases of malignant tumors to the nasal cavity and paranasal sinuses are rare. A review of the world's literature reports only four cases of antral metastases from carcinoma of gastrointestinal tract. We present a case of a stenosing adenocarcinoma of the sigmoid colon with metastases within the maxillary sinus. The ENT physical examination revealed a mass involving the right alveolar ridge, the right hard palate. CT scan of the head and the neck showed a large and irregular mass involving the right maxillary sinus, the infratemporal fossa and the pterygoid muscles with resorption of the bone of the posterior portion of the right alveolar ridge and of the posterior wall of the right maxillary sinus. The neoplastic tissue showed marked positivity for CEA and expressed cytokeratin 20, confirming the diagnosis of metastases to the maxillary sinus from colorectal adenocarcinoma. When a differential diagnosis between a second primary tumor of the maxillary sinus and a metastasis has to be carried out, the gastrointestinal tract should be taken into account and detailed immunohistochemical should be performed.