Polyps vary considerably in size and can occur singly or in clusters.
They are usually benign. Causes Generally the cause of polyps is unknown. Polyps in the larynx may be caused by exposure to tobacco smoke, an allergic reaction, or misuse of the vocal cords. Nasal polyps may be caused by allergies and infections and can recur if the underlying problem is not corrected. Incidence Polyps may arise in any mucus-producing tissue, including those found in the nose, ear, larynx , colon, rectum , and cervix.