Squamous cell carcinomas arising from the maxillary sinus have been rarely reported. The authors report the original case of a patient with squamous cell carcinoma of this site with an unusual clinical course.

A woman presented with squamous cell carcinoma of the maxillary sinus that was only diagnosed 6 months after onset of symptoms. At the time of diagnosis, the tumour had spread to the brain via the maxillary nerve and to the skin. The patient was treated by chemotherapy and radiotherapy. Four months after stopping treatment, the patient presented Brown-Sequard syndrome, for which imaging examinations were performed, demonstrating a spinal cord metastasis from her squamous cell carcinoma.

This case of squamous cell carcinoma presents several unusual features: the maxillary sinus is a rare site of squamous cell carcinoma and progression and distant metastasis have been only exceptionally described in the literature.