Olfactory loss after head and neck cancer radiation therapy.

ABSTRACT

BACKGROUND: A reduced sense of smell may be one explanation for why patients with cancer in the ear, nose and throat (ENT) region who are treated with radiation therapy lose weight. The purpose of this study was to investigate whether radiation therapy has a negative effect on olfactory function and, if so, whether this effect is dose-related. METHODOLOGY: Seventy-one patients were tested using odour-detection sensitivity and olfactory identification tests before radiation therapy and 20 months after it. RESULTS: Patients who received radiation close to the olfactory organ showed a reduced sense of smell, in both tests. A multiple regression analysis showed that the radiation dose was related to decline in the olfactory function, while age, sex, chemotherapy and interactions between these variables were not. CONCLUSION: Radiation therapy can damage olfactory cells.