A long-term study on hearing status in patients with nasopharyngeal carcinoma after radiotherapy.
OBJECTIVE
To study the long-term sensorineural hearing status after radiotherapy in patients suffering from nasopharyngeal carcinoma.


METHODS
A prospective study of 220 patients (395 ears) with a median follow-up of 36 months.


METHODS
A university hospital.


METHODS
Four criteria were needed. The patient had to have had at least 12 months of audiologic follow-up, no concurrent chronic ear disease, no direct tumor invasion of ear, and no significant sensorineural hearing loss before radiotherapy.


METHODS
Pure-tone audiography and impedance audiometry-which were performed before and at the third month after completion of radiotherapy and at a yearly interval thereafter-formed the basis of the study.


METHODS
The significance level in this study was defined as a bone conduction threshold increase of more than 10 dB between the initial audiogram and those obtained after the completion of radiotherapy. An increase of more than 30 dB was defined as severe loss.


RESULTS
Paired t test indicated that the mean bone conduction threshold before and after radiotherapy were significantly different (paired t test, p < 0.05). Logistic regression showed that patient age was related to the significant loss at speech frequency but not to the loss at 4 kHz. The presence of postradiation otitis media with effusion, preirradiation hearing status, and addition of chemotherapy were found to be not influential on hearing change.


CONCLUSIONS
Hearing deterioration may begin as early as 3 months after the completion of radiotherapy. Early change may be transient, but the effect of radiation on hearing tended to be chronic and progressive.
Wang
Ling-Feng
LF
Department of Otolaryngology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan. lifewang@cc.kmu.edu.tw
Kuo
Wen-Rei
WR
Ho
Kuen-Yao
KY
Lee
Ka-Wo
KW
Lin
Chih-Shin
CS
D000158:Acoustic Impedance Tests; D000293:Adolescent; D000328:Adult; D000368:Aged; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold; D001489:Basilar Membrane / Q000528:radiation effects; D002277:Carcinoma / Q000532:radiotherapy*; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006319:Hearing Loss, Sensorineural / Q000209:etiology*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000532:radiotherapy*; D011446:Prospective Studies; D011832:Radiation Injuries / Q000209:etiology*; D013316:Stria Vascularis / Q000528:radiation effects