Basal Cell Adenoma With Atypia in the Nasal Cavity Mimicking a Malignant Tumor.

Basal cell adenomas (BCA) arising from the nasal cavity or paranasal sinuses are very rare. A 64-year-old male patient was suspected of having a malignant tumor after undergoing preoperative computed tomography scans and magnetic resonance imaging. The intraoperative frozen section showed a malignant tumor; however, the final diagnosis revealed BCA with atypia, tubular pattern.