The maxillary sinuses lie behind the cheekbones. Tumours often develop in the maxillary sinus. The National Cancer Institute, defines a tumour as a mass of extra tissue caused by new cells produced when they are not needed.

Benign tumours generally cause no health issues. Benign tumours only cause issues when they block air flow or impede sinus drainage. Malignant tumours are cancerous. They often grow beyond the sinus region and affect other tissues.

Maxillary sinus tumours cause many symptoms in the nose. According to Cedars-Sinai common nose related symptoms are persistent nasal congestion, especially on one side; postnasal drip; frequent and persistent nosebleeds and loss of sense of smell or taste.

Pressure below the eyes and tenderness of the cheeks sometimes accompany maxillary sinus tumours. When a tumour becomes very large it presses on other tissues and causes inflammation, which leads to the pain and tenderness.

Since maxillary sinus tumours put pressure on tissues in the head they sometimes cause sinus headaches. The University of Maryland Medical Center describes sinus headaches as "a dull, deep, throbbing pain in the front of your head and face."

Maxillary sinus tumours potentially block the drainage of mucus from the cavity. This can lead to a bacterial sinus infection. Symptoms include tenderness of the face, sinus headaches, difficulty breathing and dizziness.