Preserving organs by use of multiple modalities has become protocol in treating squamous cell carcinomas of the head and neck, but cis-platinum and radiation can impair hearing. To determine the effect of cis-platinum, radiation, or a combination of these treatments on the temporal bone, we studied histopathologic slides of 15 human temporal bones: four after cis- platinum, five after radiation, two after combined treatment, and four from normal controls. Hair cells and cells in spiral ganglia were counted in reconstructed organs of Corti. Lumen-to-diameter indexes in arterioles near facial nerves were quantified for four normal controls and seven irradiated patients. Available audiograms were compared. Decreased spiral ganglion cells, loss of inner and outer hair cells, and atrophy of stria vascularis were demonstrated in groups receiving cis-platinum, radiation, and combinations, compared with age-matched controls. Arterioles around facial nerves demonstrated fibrinous clots within the intima, endothelial proliferation, and hypertrophy and fibrosis of vascular walls in smooth muscle. Fibrosis in connective tissue was clearly progressive after radiation. Cis-platinum and radiation can contribute to otologic sequelae, including sensorineural hearing losses, vascular changes, serous effusion, or fibrosis. Prophylactic treatments and techniques to deliver them should be considered for protection of temporal bones and preservation of hearing after oncologic modalities.