Infantile schwannoma of the maxillary sinus.

A rare case of a 5-year-old female with schwannoma of the maxillary sinus is presented. She had complained of painless swelling of the left cheek and hard palate for a duration of one year. Preoperatively, a CT scan strongly suggested it to be a maxillary cyst with an erupted tooth rather than neoplasm. The tumour was completely removed after embolization of the left internal maxillary artery. The tumour was composed of spindle cells in a palisading pattern and intercellular collagenous fibres. Mitotic figures and atypical nuclei were not observed. Immunohistochemically, the majority of the cells were positive for NSE and S-100 protein, whereas GFA and PCNA showed little immunoreaction. The pathological diagnosis was Antony type A of schwannoma arising in the maxillary sinus.