Multiple Primary Malignancies in Patients with Head and Neck Cancer

During the 15 years from 1967 to 1981, 3, 162 patients withcarcinoma of the head and neck were treated with radiation therapy.Among them, 262 patients (8.3%) developed two or more independentmalignancies. There were 80 patients with prior cancer. Theoverall incidence of second malignancies in patients who hadradiation therapy was 5.8%. The incidences were 8.9, 7.7, 5.2and 1.7% of index cancer in the larynx, pharynx, oral cavityand paranasal sinus, respectively. Second primaries were observedin the head and neck (36%), digestive tract (35%), lung (19%)and the remaining 10% in other bodily sites. Of the 1, 486 patientswho survived for five years or more after radiation therapy,only 10 (0.7%) developed second malignancies within the previousradiation field.