Results at the end of chemotherapy and during the long-term follow-up.
Auditory assessment was performed in all children involved in this study before the beginning of chemotherapy and they showed normal hearing. Thirty-eight children completed the long-term audiological follow-up equal or longer than five years (range 60–108 months with a mean of 74 months). At the end of chemotherapy 15/38 (39.5%) children presented ototoxicity (SIOP criteria > 0), of which 10/38 (26.3%) exhibited a progressive hearing loss during the long-term follow-up whereas 5/38 (13.1%) did not progress furtherly hearing loss. In addiction at the long-term follow-up we observed 5/38 (13.1%) new cases with late onset hearing loss. Finally, at the end of the 5-years follow-up 20/38 (52.5%) had ototoxicity (SIOP criteria > 0). No patient showed hearing improvement during the hearing monitoring. Details on grading percentages are showed in Fig. 1. The percentage of children with ototoxicity at the long-term follow-up was significantly increased compared to that at the end of chemotherapy 39.5% versus 52.5% (p < 0.001).