Test Identifies Early Chemotherapy-Related Hearing Loss

NEW YORK APR 20, 2007 (Reuters Health) - Among children undergoing platinum-based chemotherapy, early changes in auditory function can be detected using extended high-frequency (EHF) audiometry and evoked distortion product otoacoustic emissions (DPOAEs), according to a report in the April 1st Journal of Clinical Oncology.

Platinum chemotherapy is associated with a risk for permanent sensorineural hearing loss in children, the authors explain, but standard monitoring lacks sensitivity in detecting early ototoxicity.

Dr. Edward A. Neuwelt and colleagues from Oregon Health and Science University, Portland, evaluated the feasibility of EHF audiometry and DPOAEs for ototoxicity monitoring in 32 children with normal hearing at baseline treated with platinum chemotherapy. The team investigated whether changes in these measures occurred earlier than changes in conventional audiometry.

Bilateral ototoxicity was detected by conventional audiometry in 20 of the 32 patients (62.5%), the authors report, whereas EHF detected bilateral ototoxicity in 16 of 17 patients tested (94.12%) and DPOAEs were decreased bilaterally in 26 of 32 children (81.2%).

EHF was earliest to identify ototoxicity, the researchers note, followed by DPOAEs and then conventional audiometry.

"EHF testing was feasible and reliable in children who were 5 years and older," the investigators say. "DPOAEs are especially valuable for monitoring ototoxicity in very young children who may not consistently provide reliable, complete, ear-specific pure-tone threshold responses."

They say future studies might show, as these results suggest, if early DPOAE or EHF changes identify children who are at greater risk for acquiring ototoxicity. If so, "it may be possible to adjust treatment or use a protective agent to avoid communicatively significant hearing loss."

SOURCE:

• J Clin Oncol 2007;25:1190-1195.