Transtympanic Injections of N-acetylcysteine and Dexamethasone for Prevention of Cisplatin-Induced Ototoxicity: Double Blind Randomized Clinical Trial.

OBJECTIVE: Cisplatin is a potent chemotherapeutic agent that is used against a variety of tumors. The most common side effect of cisplatin is ototoxicity. This dose-related hearing impairment is high frequency, bilateral, and permanent. Unfortunately, there is no prophylactic protocol, and, in current clinical practice, the treatment of cancer with cisplatin is interrupted when ototoxicity develops or the resulting hearing impairment is tolerated as an acceptable side effect of cancer treatment. The aim of this study is to compare transtympanic injections of N-acetylcysteine and dexamethasone (both of which have shown substantial otoprotective activity) for the prevention of cisplatin-induced ototoxicity.

METHODS: A double blind randomised clinical trial study of 60 cisplatin-treated patients was performed in Shahid Sadoughi Hospital in 2016-2017. Transtympanic injection of N-acetylcysteine (10%) and dexamethasone was performed. Hearing acuity was evaluated by an audiologist blinded to the treated ears before each cycle with pure tone audiometry (PTA) and six months later.

RESULTS: Altogether, 114 transtympanic infusions were performed (57 in each group). The data were analyzed by the Fisher test and chi-squared. In the ears with N-acetylcysteine, no significant changes in auditory thresholds were recorded. In the ears with dexamethasone, cisplatin induced a significant decrease of auditory thresholds at the 8000 Hz frequency band (P = 0.001).

CONCLUSION: Transtympanic injections of N-acetylcysteineas a safe and inexpensive antioxidant agent seem to be an effective otoprotective strategy for the prevention of cisplatin-induced ototoxicity and for increasing the quality of life, especially in children.