Prevention of Cisplatin-Induced Hearing Loss by Intratympanic Dexamethasone Treatment

Cisplatin is a widely used chemotherapeutic agent for the treatment of various malignant neoplasms, including testicular, ovarian, bladder, cervix uteri, head and neck and lung cancers. One of the common side-effects of this drug is bilateral, symmetric, progressive and usually irreversible sensorineural hearing loss. Cisplatin induces cochlear toxicity by the production of reactive oxygen species (ROS). Dexamethasone treatment is currently practiced for various pathologies afflicting the inner ear. The positive effect of Dexamethasone is attributed to it's anti ROS activity and it's capability to up-regulate cochlear anti ROS enzymes. In order to reach higher inner ear concentration of the drug while avoiding it's undesirable systemic side-effects, Intratympanic (IT) delivery of Dexamethasone became vastly used in the last decades for the treatment of sudden sensorineural hearing loss and Meniere's disease. Dexamethasone inserted IT, diffuse across the round window into the inner ear perilymph where it exerts its therapeutic effects. The investigators review of the literature yielded three animal studies which examined the protective effect of IT dexamethasone in the prevention of cisplatin-induced hearing loss. These studies demonstrated promising results pointing to the potential for IT dexamethasone in the prevention of cisplatin ototoxicity in humans. The purpose of this study is to examine possible protective effect of IT dexamethasone on cisplatin-induced hearing loss, in humans. The study hypothesis is that IT dexamethasone treatment would prevent cisplatin-induced hearing loss.