Ontology highlight
ABSTRACT: BACKGROUND
Radiotherapy to the cochlea and cisplatin exposure are both associated with hearing loss (HL) in medulloblastoma survivors. Here we report late outcomes in survivors with ≥1 year audiogram testing. METHODS
Prospective medulloblastoma trial participants (clinicaltrials.gov: NCT01063114/NCT00105560) with ≥1 years of audiogram follow-up (FU, n=110 pts) comprised the study cohort. HL was graded using the SIOP-Boston ototoxicity scales (0-4) for each ear. Associations between grade 3 HL and mean cochlear radiation dose and cumulative cisplatin dose were evaluated. Target cisplatin dose was 450 mg/m2 but most patients did not receive full dose as dose reductions were used when ototoxicity was detected during chemotherapy. FINDINGS
Median follow-up was 4.0 years (range 1-10). At baseline, 10 ears (4.5%) had grade 3 HL. At latest FU, an additional 49 ears developed grade 3 HL (23.3%). There was no grade 4 HL. Median average cochlear dose across both ears was 29.9 Gy (20.8-50.6) and median cisplatin dose was 375.0 mg/m2 (60.0-583.0). Mean cochlear radiation dose for grade 3 HL (n=56) was 32.5Gy (24.1-47.0), compared with 31.8Gy (20.8-50.6, p=0.19). Mean cisplatin dose for grade 3 HL was 347.3mg/m2 (180.0-450.0), compared with 374.2mg/m2 for grade 0-2 ears (60.0-583.0, p=0.05). INTERPRETATION
Significant hearing deficits (SIOP-Boston grade 3) develop in approximately 23.3% of medulloblastoma patients. In this cohort, higher mean radiation dose did not affect HL rates. The lower mean cumulative cisplatin dose in pts with grade 3 HL suggests cisplatin ototoxicity is driving HL, and that host susceptibility may play a role.
SUBMITTER: Byun J
PROVIDER: S-EPMC6012575 | biostudies-literature | 2018 Jun
REPOSITORIES: biostudies-literature