Severe ototoxicity following carboplatin-containing conditioning regimen for autologous marrow transplantation for neuroblastoma

Children with neuroblastoma receiving high-dose carboplatin as part of their conditioning regimen for autologous marrow transplantation have a high incidence of speech frequency hearing loss. We evaluated hearing loss in 11 children with advanced stage neuroblastoma who underwent autologous marrow transplantation, following a conditioning regimen containing high-dose carboplatin (2 g/m(2), total dose). Audiometric evaluations were obtained at diagnosis, prior to and following transplant. Exposure to other known ototoxins also was assessed. All patients sustained worsening of hearing following high-dose carboplatin. Nine of the 11 children (82%) had evidence of speech frequency hearing loss post transplant for which hearing aids were recommended (grades 3-4), Three of the nine children had speech frequency loss prior to transplant which progressed following transplant. The entire group was heavily pre-treated with platinum-containing chemotherapy pre-BMT and had extensive exposure to other ototoxins, including aminoglycoside antibiotics, diuretics, and noise exposure - all of which could have exacerbated the effects of carboplatin. High-dose carboplatin is ototoxic, particularly in patients who have been primed with previous platinum therapy or other ototoxic agents. We conclude that further efforts are needed to monitor and minimize this complication. In cases where hearing loss is inevitable due to cumulative ototoxic exposures, families need to be adequately prepared for the tradeoffs of potentially curable therapy.