Sensorineural hearing loss in patients treated for nasopharyngeal carcinoma: a prospective study of the effect of radiation and cisplatin treatment.
OBJECTIVE
The pattern of sensorineural hearing loss (SNHL) after primary treatment for nasopharyngeal carcinoma (NPC) was studied, and the effect of cisplatin, radiotherapy does, and fractionation were evaluated.


METHODS
One hundred thirty-two patients, 227 ears, and 1100 audiogram reports were analyzed. Radiotherapy dose ranged from 59.5 to 76.5 Gy. Fifty-two patients received preirradiation cisplatin, total dose 100-185 mg/m(2). Serial postirradiation bone conduction thresholds at 0.5 kHz, 1 kHz, 2 kHz, and 4 kHz were compared with pretreatment thresholds at respective frequencies. Increase of at least 15 dB was considered as significant and was further grouped as transient or persistent SNHL. Univariate and multivariate analyses were performed to identify predicting factors for persistent SNHL.


RESULTS
At median follow-up of 30 months, 24.2% of ears developed persistent SNHL. High frequency was more affected than low frequencies, 22 vs. 5.3%. Males were more affected than females, 29.4 vs. 15.5%, p = 0.0132. Incidence of persistent SNHL increased with age, with 0, 17.2, and 37.4% of patients aged under 30, between 30-50 and over 50 affected, respectively, p = 0.0001. High incidence was found in patient with postirradiation serous otitis media (SOM), 46.9%. Chemotherapy with cisplatin and radiation dose or fractionation had no significant effect. Multivariate analysis confirmed age, sex, and postirradiation SOM as significant prognostic factors for persistent SNHL.


CONCLUSIONS
Transient and persistent SNHL occurred after radiotherapy, more commonly affecting high frequency. A low dose of preirradiation cisplatin did not increase the risk. A dose fractionation effect of radiotherapy was not confirmed in this study.
Kwong
D L
DL
Department of Radiotherapy and Oncology, University of Hong Kong, Queen Mary Hospital, Hong Kong.
Wei
W I
WI
Sham
J S
JS
Ho
W K
WK
Yuen
P W
PW
Chua
D T
DT
Au
D K
DK
Wu
P M
PM
Choy
D T
DT
D000293:Adolescent; D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects*; D002945:Cisplatin / Q000009:adverse effects*; D003131:Combined Modality Therapy; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009303:Nasopharyngeal Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy*; D010034:Otitis Media with Effusion / Q000209:etiology; D011446:Prospective Studies; D011838:Radiation-Sensitizing Agents / Q000009:adverse effects*; D012737:Sex Factors
D000970:Antineoplastic Agents; D011838:Radiation-Sensitizing Agents; D002945:Cisplatin