PURPOSE: To investigate the incidence of radiation-induced @entity2167 according to the total dose delivered to specific parts of the auditory system, fractionation, and chemotherapy. METHODS AND MATERIALS: Records of 325 @entity1 treated for primary @entity135 with curative intent who received radiotherapy between 1964 and 2000 (median follow-up, 5.4 years) were retrospectively reviewed. Reconstructions of the treatment plans were generated to estimate the doses received by components of the auditory system. RESULTS: Radiotherapy-induced morbidity developed in 41.8% of @entity1 (external ear, 33.2%; middle ear, 28.6%; and inner ear, 26.8%). Univariate/multivariate analyses indicate that total dose received by parts of the auditory system seem to be significant, though fractionation and chemoradiation may contribute to the incidence of @entity2167 . @entity1274 ( @entity1274 ) was observed in 49 @entity1 (15.1%). Univariate and multivariate analyses indicated that age (p = 0.0177 and p = 0.005) and dose to cochlea (p < 0.0001 and p < 0.0001) were significant, and chemoradiation (p = 0.0281 and p = 0.006) may increase the incidence of @entity1274 . Five-year and 10-year actuarial risk of clinically overt @entity1274 increased to 37% (p > 0.0001) above doses of 60.5 Gy compared to 3% at doses below 60.5 Gy. For @entity1 treated with adjuvant chemotherapy, clinically overt @entity1274 increased to 30% compared to 18% in the no-chemotherapy group at 10 years (p = 0.0281). CONCLUSION: Radiotherapy @entity137 was observed in all parts of the auditory system with median doses for incidence varying between 60 Gy to 66 Gy. Total dose to organ seems to be a significant factor though fractionation and chemo-radiation may contribute to @entity2167 .

XXXX after radiotherapy for @entity135 .

@entity1 :: ('9606', 'Species') :: ['patients'] @entity135 :: ('MESH:D006258', 'Disease') :: ['extracranial head and neck tumors'] @entity137 :: ('MESH:D064420', 'Disease') :: ['toxicity'] @entity2167 :: ('MESH:D006311', 'Disease') :: ['ototoxicities', 'ototoxicity'] @entity1274 :: ('MESH:D006319', 'Disease') :: ['Sensorineural hearing loss', 'SNHL']
@entity2167 :: (MESH:D006311,Disease) :: ['Ototoxicity']
