RESUMO
Ototoxicity is a devastating direct, irreversible side effect of platinum use in children with cancer, with its consequent effect on speech, language and social development, quality of life and adult productivity. Cisplatin, an essential chemotherapeutic agent for the treatment of solid tumors in children, is a DNA cross-linking agent. Which causes hearing loss in 50-70% of cisplatin treated children. Fortunately, to prevent hearing loss, sodium thiosulfate (STS), which binds to cisplatin, and reduces the superoxides in both tumor and outer hair cells of the cochlea has now been discovered to be an effective and safe otoprotectant if administered correctly. The aim of this perspective paper is to explore the key safety issues and challenges important for pediatric oncologists and pharmacists when considering the clinical use of STS as an otoprotectant for children and adolescents receiving cisplatin. These include: the choice of the formulation; the timing, both that of the STS in relation to cisplatin as well as the timing of the cisplatin infusion itself; the dosing; the challenge left by the definition of localized versus disseminated disease and the difference in indication for STS, between cisplatin treated patients and those receiving another platinum chemotherapeutic agent, carboplatin.
RESUMO
PURPOSE: Hearing loss occurs in 50%-70% of children treated with cisplatin. Scientific efforts have led to the recent approval of a pediatric formula of intravenous sodium thiosulfate (STS) for otoprotection by the US Food and Drug Administration, the European Medicines Agency, and the Medicines and Health Regulatory Authority in the United Kingdom. To inform stakeholders regarding the clinical utility of STS, the current review summarizes available literature on the efficacy, pharmacokinetics (PK), and safety of systemic STS to minimize cisplatin-induced hearing loss (CIHL). DESIGN: A comprehensive narrative review is presented. RESULTS: Thirty-one articles were summarized. Overall, systemic STS effectively reduces CIHL in the preclinical and controlled clinical study settings, in both adults and children with cancer. The extent of CIHL reduction depends on the timing and dosing of STS in relation to cisplatin. Both preclinical and clinical data suggest that systemic STS may affect plasma platinum levels, but studies are inconclusive. Delayed systemic administration of STS, at 6 hours after the cisplatin infusion, does not affect cisplatin-induced inhibition of tumor growth or cellular cytotoxicity in the preclinical setting, nor affect cisplatin efficacy and survival in children with localized disease in the clinical setting. CONCLUSION: Systemic administration of STS effectively reduces the development and degree of CIHL in both the preclinical and clinical settings. More studies are needed on the PK of STS and cisplatin drug combinations, the efficacy and safety of STS in patients with disseminated disease, and the ability of STS to prevent further deterioration of pre-established hearing loss.
RESUMO
PURPOSE: The frequency and patterns of HL in a HNRMS survivor cohort were investigated. A dose-effect relationship between the dose to the cochlea and HL was explored. METHODS: Dutch survivors treated for HNRMS between 1993 and 2017 with no relapse and at least two years after the end of treatment were eligible for inclusion. The survivors were evaluated for HL with pure-tone audiometry. HL was graded according to the Muenster, Common Terminology Criteria for Adverse Events (CTCAE) v4.03 and International Society for Paediatric Oncology (SIOP) classification. We defined deleterious HL as Muenster ≥ 2b, CTCAE ≥ 2, and SIOP ≥ 2. Mixed-effects logistic regression was used to search for the dose-effect relationship between the irradiation dose to the cochlea and the occurrence of HL. RESULTS: Forty-two HNRMS survivors underwent pure-tone audiometry. The Muenster, CTCAE and SIOP classification showed that 19.0% (n = 8), 14.2% (n = 6) and 11.9% (n = 5) of survivors suffered from HL, respectively. A low-frequency HL pattern with normal hearing or milder hearing loss in the higher frequencies was seen in four survivors. The maximum cochlear irradiation dose was significantly associated with HL (≥Muenster 2b) (p = 0.047). In our series, HL (≥Muenster 2b) was especially observed when the maximum dose to the cochlea exceeded 19 Gy. CONCLUSION: HL occurred in up to 19% of survivors of HNRMS. More research is needed on HL patterns in HNRMS survivors and on radiotherapy dose-effect relationships.
RESUMO
BACKGROUND: Some children with central nervous system (CNS) and solid tumors are at risk to develop ototoxicity during treatment. Up to now, several risk factors have been identified that may contribute to ototoxicity, such as platinum derivates, cranial irradiation, and brain surgery. Comedication, like antibiotics and diuretics, is known to enhance ototoxicity, but their independent influence has not been investigated in childhood cancer patients. Recommendations for hearing loss screening are missing or vary highly across treatment protocols. Additionally, adherence to existing screening guidelines is not always optimal. Currently, knowledge is lacking on the prevalence of ototoxicity. OBJECTIVE: The aim of the Study on Prevalence and Determinants of Ototoxicity During Treatment of Childhood Cancer (SOUND) is to determine the feasibility of audiological testing and to determine the prevalence and determinants of ototoxicity during treatment for childhood cancer in a national cohort of patients with solid and CNS tumors. METHODS: The SOUND study is a prospective cohort study in the national childhood cancer center in the Netherlands. The study aims to include all children aged 0 to 19 years with a newly diagnosed CNS or solid tumor. Part of these patients will get audiological examination as part of their standard of care (stratum 1). Patients in which audiological examination is not the standard of care will be invited for inclusion in stratum 2. Age-dependent audiological assessments will be pursued before the start of treatment and within 3 months after the end of treatment. Apart from hearing loss, we will investigate the feasibility to screen patients for tinnitus and vertigo prevalence after cancer treatment. This study will also determine the independent contribution of antibiotics and diuretics on ototoxicity. RESULTS: This study was approved by the Medical Research Ethics Committee Utrecht (Identifier 20-417/M). Currently, we are in the process of recruitment for this study. CONCLUSIONS: The SOUND study will raise awareness about the presence of ototoxicity during the treatment of children with CNS or solid tumors. It will give insight into the prevalence and independent clinical and cotreatment-related determinants of ototoxicity. This is important for the identification of future high-risk patients. Thereby, the study will provide a basis for the selection of patients who will benefit from innovative otoprotective intervention trials during childhood cancer treatment that are currently being prepared. TRIAL REGISTRATION: Netherlands Trial Register NL8881; https://www.trialregister.nl/trial/8881. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/34297.
