Table 5 Criteria and radiation doses to the cochlea in correlation with the incidences of SNHL
From: Sensorineural hearing loss after concurrent chemoradiotherapy in nasopharyngeal cancer patients
Study | RT | Criteria | Doses to cochlea | Median follow up & SNHL (per ear) |
|---|---|---|---|---|
Kwong et al[10] | Conv RT + chemo (227 ears) | >15 dB at each frequency | not defined | 30 months 24.2% |
Oh et al [19] | Conv RT + chemo (48 ears) | >15 dB at 4 kHz and PTA | mean inner ear dose 66.2 ± 6.2 | 1 year 29.2% |
Ho et al [12] | Conv RT + chemo (526 ears) | >10 dB at 4 kHz and PTA | estimated 70-91 Gy, 2.5-3.5 Gy/F | 4.5 years, 4 kHz 60% PTA 18% |
Chan et al [5] | Conf RT vs Conf RT + chemo (170 ears) | >15 dB at 4 kHz | mean cochlea dose 33-71.7 Gy | 24 months 33.3% vs 55% (Conf RT vs Conf RT+ chemo) |
Chen et al.[4] | Conf RT+ chemo (44 ears) | >20 dB at one frequency >10 dB at two frequencies | 28.4 - 70.0 Gy | 29 months 57% |
Our study | Conv RT +chemo vs IMRT+ chemo (134 ears, 68 patients) | >15 db loss at 4 kHz and PTA | Mean cochlea dose 25.09-75.54 Gy (IMRT) | 14 months 4 kHz Conv 48.75% IMRT 37% PTA Conv 5% IMRT 7.4% |