(ChemotherapyAdvisor) – Young children with retinoblastoma treated with systemic carboplatin have a higher incidence of ototoxicity than previously reported, calling for routine, thorough, long-term audiologic monitoring, a study in the Journal of Clinical Oncology published online February 27 reported. Children younger than 6 months of age at treatment initiation were more likely to have ototoxicity than older patients.
Audiologic test results of 60 patients treated front-line with systemic carboplatin and vincristine according to the St Jude Children’s Research Hospital retinoblastoma-3 (RET-3) protocol (8 cycles of vincristine and carboplatin administered at 3-week intervals; n=23) or best clinical management (n=37) were reviewed to assess incidence of ototoxicity and its risk factors. The investigators evaluated ototoxicity using three different grading systems: Brock, Children’s Cancer Group, and NCI-CTCAE.
Among the 12 patients (20%) who developed ototoxicity after treatment initiation, ototoxicity resolved in 2; of the 10 (17%) who had sustained hearing loss as documented at their most recent audiologic evaluation, 9 had grade 3 or 4 ototoxicity and 9 were <6 months of age at the start of chemotherapy.
“Age at the start of chemotherapy was the only risk factor identified as a significant predictor of sustained hearing loss,” the study authors wrote. Younger age was also associated with an increased incidence of hearing loss. In identifying patients with ototoxicity, agreement was greatest between the Brock and Children’s Cancer Group systems; however, the three ototoxicity grading systems showed good overall agreement.