Long term platinum-induced ototoxicity in pediatric patients

Ototoxicity among cisplatin, carboplatin, and oxaliplatin in zebrafish model

Platinum-based antineoplastic drugs, including cisplatin, carboplatin, and oxaliplatin, are widely used in the treatment of various cancers. Ototoxicity is a common adverse effect of platinum-based drugs. Ototoxicity leads to irreversible hearing impairment. We hypothesize that different platinum-based drugs exhibit varying ototoxic concentrations, time effects, and ototoxic mechanisms. We tested this hypothesis by using a zebrafish model (pvalb3b: TagGFP) to assess the viability of hair cells collected from zebrafish larvae. Cisplatin, carboplatin, and oxaliplatin were administered at dosages of 100, 200, or 400 μM, and the ototoxic effects of these drugs were assessed 1, 2, or 3 h after administration. Fm4-64 and a TUNEL assay were used to label the membranes of living hair cells and to detect cell apoptosis, respectively. We observed that >50% of hair cells were damaged at 1 h after cisplatin (100 μM) exposure, and this ototoxic effect increased at higher dosages and over time. Owing to the smaller ototoxic effects of carboplatin and oxaliplatin, we conducted higher-strength and longer-duration experiments with these drugs. Neither carboplatin nor oxaliplatin was obviously ototoxic, even at 1600 μM and after 6 h. Moreover, only cisplatin damaged the membranes of the hair cells. Cell apoptosis and significantly increased antioxidant gene expression were observed in only the cisplatin group. In conclusion, cisplatin significantly damages sensory hair cells and has notable dosage and time effects. Carboplatin and oxaliplatin are less ototoxic than cisplatin, likely due to having different ototoxic mechanisms than cisplatin.

Association of hearing loss with patient-reported functional outcomes in adult survivors of childhood cancer

BACKGROUND

Hearing loss is prevalent following ototoxic therapy for childhood cancer. Associations between hearing loss, self-perceived hearing handicap, and functional outcomes have not been examined in survivors.

METHODS

Adult survivors treated with platinum or head and neck radiotherapy with hearing loss were recruited. A total of 237 survivors (median age at survey = 37.0 years [range = 30.0-45.0 years]; median = 29.1 years [range = 22.4-35.0 years] since diagnosis; median = 4.0 years [range = 2.9-7.7 years] from last audiogram to survey) completed the Hearing Handicap Inventory for Adults and questionnaires on social and emotional functioning and hearing aid use. Hearing loss severity was defined according to Chang criteria. Multivariable logistic regression models estimated odds ratios (ORs) and 95% confidence intervals (CIs) for associations between hearing loss, hearing handicap, functional outcomes, and hearing aid use with adjustment for sex, race, age at hearing loss diagnosis, and age at survey.

RESULTS

Two-thirds of survivors had severe hearing loss, which was associated with increased likelihood of hearing handicap (mild-moderate handicap: OR = 2.72, 95% CI = 1.35 to 5.47; severe handicap: OR = 5.99, 95% CI = 2.72 to 13.18). Survivors with severe hearing handicap had an increased likelihood of social isolation (OR = 8.76, 95% CI = 3.62 to 21.20), depression (OR = 9.11, 95% CI = 3.46 to 24.02), anxiety (OR = 17.57, 95% CI = 3.77 to 81.84), reduced personal income (OR = 2.82, 95% CI = 1.46 to 5.43), and less than full-time employment (OR = 2.47, 95% CI = 1.30 to 4.70). Survivors who did not use a recommended hearing aid were twice as likely to have less than full-time employment (OR = 2.26, 95% CI = 1.10 to 4.61) and reduced personal income (OR = 2.24, 95% CI = 1.08 to 4.63) compared with survivors who wore a hearing aid.

CONCLUSION

Self-perceived hearing handicap beyond measured hearing loss is associated with reduced functional outcomes. Assessment of hearing handicap may facilitate targeted interventions in adult survivors with hearing loss.

Cisplatin-induced ototoxicity: a novel approach to an ancient problem

With the scarcity of pharmacological otoprotective agents against cisplatin-induced ototoxicity (CIO), researchers find themselves compelled to look at and navigate all possible strategies to identify ways to prevent CIO. One of these promising strategies is pharmacogenomic implementation. This strategy aims for identifying and detecting high-risk genetic variants to tailor cisplatin therapy to reach the best survival outcomes with the least risk of ototoxicity.

Platinum drugs-related safety profile: The latest five-year analysis from FDA adverse event reporting system data

Background

With the widespread application of platinum drugs in antitumor therapy, the incidence of platinum drug adverse events (ADEs) is always severe. This study aimed to explore the adverse event signals of Cisplatin, Carboplatin and Oxaliplatin, three widely used platinum-containing drugs, and to provide a reference for rational individualized clinical drug use.

Methods

The adverse event report data of the three platinum drugs from the first quarter of 2017 to the fourth quarter of 2021 were extracted from the FAERS database, and the data mining and risk factors for the relevant reports were carried out using the reporting odds ratio (ROR) method the proportional reporting ratio (PRR)and the comprehensive criteria (MHRA) method.

Results

A total of 1853 effective adverse event signals were obtained for the three platinum agents, including 558 effective signals for Cisplatin, 896 effective signals for Carboplatin, and 399 effective signals for Oxaliplatin. The signals involve 23 effective different system organs (SOCs). The adverse events of Cisplatin are mainly fixed on blood and lymphatic system diseases, gastrointestinal diseases, systemic diseases and various reactions at the administration site. The adverse events of Carboplatin are mainly focused on blood and lymphatic system diseases, respiratory system, thoracic and mediastinal diseases, while the adverse events of Oxaliplatin are mainly concentrated in respiratory system, thoracic and mediastinal diseases, various nervous system diseases, and gastrointestinal system diseases.

Conclusion

It was found that the main systems involved in common adverse events of platinum drugs are different, and the correlation strength of platinum drugs with the certain adverse events of each system is different.

Changes in vestibular and cochlear function following platinum-based chemotherapy: A preliminary report

OBJECTIVES

This study investigated the changes in vestibular and cochlear function in patients receiving platinum-based chemotherapy.

METHODS

A longitudinal study of 32 participants (10-70 years) receiving chemotherapy participated in the study. Baseline and exit vestibular and hearing assessments that included video head impulse (VHIT) testing, cervical and ocular vestibular evoked myogenic potentials (VEMP), dynamic visual acuity (DVA) and pure-tone audiometry were performed at the patient's treatment venue.

RESULTS

Half (50%) of the participants showed cochleotoxicity from baseline to exit testing, with left ears significantly more affected than right ears. There was no consistent relationship between hearing loss and vestibular dysfunction. DVA yielded normal results at baseline and exit testing in all participants. VEMP responses were absent in 28.1% of participants at baseline, reflecting the challenges of using VEMP for monitoring. VEMP and VHIT results showed a statistically significant (p < 0.05) decline in results from baseline to exit testing; however, participants did not report symptoms related to vestibular dysfunction. VHIT also showed left ears significantly (p < 0.05) more affected than right ears.

CONCLUSION

VHIT proved to be a valuable measure of changes in vestibular function secondary to ototoxicity. Future investigations should determine vestibulotoxicity criteria and optimal protocols for vestibulotoxicity monitoring at the patient's treatment venue.

Global burden of ototoxic hearing loss associated with platinum-based cancer treatment: A systematic review and meta-analysis

Platinum-based chemotherapeutic agents cisplatin and carboplatin are widely used in cancer treatment worldwide and may result in ototoxic hearing loss. The high incidence of cancer and salient ototoxic effects of platinum-based compounds pose a global public health threat. The purpose of this study was twofold. First, to estimate the prevalence of ototoxic hearing loss associated with treatment with cisplatin and/or carboplatin via a systematic review and meta-analysis. Second, to estimate the annual global burden of ototoxic hearing loss associated with exposure to cisplatin and/or carboplatin. For the systematic review, three databases were searched (Ovid Medline, Ovid Embase, and Web of Science Core Collection) and studies that reported prevalence of objectively measured ototoxic hearing loss in cancer patients were included. A random effects meta-analysis determined pooled prevalence (95% confidence intervals [CI]) of ototoxic hearing loss overall, and estimates were stratified by treatment and patient attributes. Estimates of ototoxic hearing loss burden were created with published global estimates of incident cancers often treated with platinum-based compounds and cancer-specific treatment rates. Eighty-seven records (n = 5077 individuals) were included in the meta-analysis. Pooled prevalence of ototoxic hearing loss associated with cisplatin and/or carboplatin exposure was 43.17% [CI 37.93–48.56%]. Prevalence estimates were higher for regimens involving cisplatin (cisplatin only: 49.21% [CI 42.62–55.82%]; cisplatin & carboplatin: 56.05% [CI 45.12–66.43%]) versus carboplatin only (13.47% [CI 8.68–20.32%]). Our crude estimates of burden indicated approximately one million individuals worldwide are likely exposed to cisplatin and/or carboplatin, which would result in almost half a million cases of hearing loss per year, globally. There is an urgent need to reduce impacts of ototoxicity in cancer patients. This can be partially achieved by implementing existing strategies focused on primary, secondary, and tertiary hearing loss prevention. Primary ototoxicity prevention via otoprotectants should be a research and policy priority.

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An estimated one million people are exposed to chemotherapeutic drugs per year.

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An estimated half a million cases of hearing loss per year are from chemotherapy.

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Hearing loss prevalence after exposure to cisplatin and/or carboplatin is 43%.

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Primary, secondary and tertiary prevention of hearing loss should be prioritized.

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Ototoxic hearing loss prevention is a global public health priority.

Supporting Cells and Their Potential Roles in Cisplatin-Induced Ototoxicity

Cisplatin is a known ototoxic chemotherapy drug, causing irreversible hearing loss. Evidence has shown that cisplatin causes inner ear damage as a result of adduct formation, a proinflammatory environment and the generation of reactive oxygen species within the inner ear. The main cochlear targets for cisplatin are commonly known to be the outer hair cells, the stria vascularis and the spiral ganglion neurons. Further evidence has shown that certain transporters can mediate cisplatin influx into the inner ear cells including organic cation transporter 2 (OCT2) and the copper transporter Ctr1. However, the expression profiles for these transporters within inner ear cells are not consistent in the literature, and expression of OCT2 and Ctr1 has also been observed in supporting cells. Organ of Corti supporting cells are essential for hair cell activity and survival. Special interest has been devoted to gap junction expression by these cells as certain mutations have been linked to hearing loss. Interestingly, cisplatin appears to affect connexin expression in the inner ear. While investigations regarding cisplatin-induced hearing loss have been focused mainly on the known targets previously mentioned, the role of supporting cells for cisplatin-induced ototoxicity has been overlooked. In this mini review, we discuss the implications of supporting cells expressing OCT2 and Ctr1 as well as the potential role of gap junctions in cisplatin-induced cytotoxicity.

Long-term auditory follow-up in the management of pediatric platinum-induced ototoxicity

PURPOSE

Irreversible bilateral sensorineural hearing loss is a common side effect of platinum compounds. Because of the extended overall survival, a prolonged hearing surveillance and management of hearing impairments are emerging concerns for pediatric oncology.

METHODS

In this retrospective observational study, we enrolled 38 children out of 116 treated at our institution by chemotherapy (cisplatin and/or carboplatin) with or without irradiation between 2007 and 2014, submitted to hearing monitoring before every cycle of chemotherapy, and who completed a 5-year long-term audiological follow-up. Chemotherapy regimens, demographic findings, cumulative doses, and cranial irradiation were compared.

RESULTS

At the end of 5-year follow-up, ototoxicity was significantly increased compared to that observed at the end of chemotherapy (52.5% vs 39.5%, p < 0.001). A late onset of hearing loss was experienced in 13.1% of children, while in 26.3% progressive hearing loss was measured. Deafness at the end of chemotherapy and irradiation were significant prognostic factors for late ototoxicity outcomes (Odds Ratio 7.2-CI 1.67-31.1-p < 0.01 and 5.25-CI 1.26-21.86-p < 0.01 respectively). No significant differences were found between cisplatin and combined treatment (i.e., cisplatin shifted to carboplatin during monitoring for the onset of ototoxicity) and ototoxicity was not associated with platinum compounds cumulative dose (p > 0.05). 13.1% of children needed hearing aids at the end of follow-up.

CONCLUSION

Long-term monitoring of at least 5 years prevents the harmful effects of hearing deprivation identifying late onset/progressive hearing loss after platinum compound chemotherapy in children thanks to early hearing rehabilitation, especially in those who underwent multimodal therapy or subjected to irradiation.

Imbalance Associated With Cisplatin Chemotherapy in Adult Cancer Survivors: A Clinical Study

OBJECTIVE

This study investigated balance problems and vestibular function in adult cancer survivors who had completed cisplatin chemotherapy treatment.

STUDY DESIGN

Observational cross-sectional study.

SETTING

Tertiary care center.

PATIENTS

Adult survivors of cancer who had completed cisplatin treatment.

MAIN OUTCOME MEASURES

Patient-reported balance symptoms were evaluated by a semistructured clinical interview. Patients underwent bedside clinical tests including Dynamic Visual Acuity test, Modified Clinical Testing of Sensory Interaction and Balance (CTSIB-m), and vibration sense testing to detect peripheral neuropathy. The video Head Impulse Test (vHIT) of all semicircular canals was performed.

RESULTS

Eleven of 65 patients (17%) reported some balance symptoms after cisplatin therapy, including vertigo, dizziness, unsteadiness, and falls. Vertigo was the most common balance symptom, reported by six patients (9.2%), and the clinical histories of these patients were consistent with benign paroxysmal positional vertigo. Three patients (5%) had abnormal results of the CTSIB-m test, and they were the same patients who reported falls. There was a significant association of peripheral neuropathy detected by vibration test and balance symptoms. All patients had normal vHIT results in all semicircular canals.

CONCLUSIONS

Balance symptoms after cisplatin treatment occurred in 17% of adult cancer survivors. Patients with peripheral neuropathy were more likely to have balance symptoms. The CTSIB-m test is a useful bedside physical examination to identify patients with a high risk of fall. Though there was no vestibular dysfunction detected by the vHIT in cancer survivors after cisplatin therapy, benign paroxysmal positional vertigo was relatively prevalent in this group of patients.

Speech perception 30 years after cisplatin-based chemotherapy in adults: limited clinical relevance of long-term ototoxicity?

BACKGROUND

Cisplatin-based chemotherapy (CBCT) can cause high-frequency hearing loss, but little is known about the development and clinical relevance of this hearing loss in survivors of adult-onset cancer with very long-term follow-up. This case-control study investigates hearing and speech perception both in quiet and with background noise 30-years after CBCT.

PATIENTS AND METHODS

One-hundred-and-one patients (Cases) who received CBCT for testicular cancer between 1980 and 1994 were assessed with pure-tone audiometry (.125 - 8 kHz) and speech perception tests including hearing in noise test (HINT). Self-reported hearing and tinnitus was scored by participants. Results were compared with 30 age-matched controls.

RESULTS

The median age of Cases and Controls was 60 (46 - 83) and 61 years (51 - 74), respectively. The median observation time for Cases was 30 years (22 - 37). Compared with Controls, Cases had 8 and 19 dB worse age-adjusted high-frequency hearing at 6 and 8 kHz, respectively (p <.05), while thresholds at lower frequencies did not differ. All but four Cases reached 100% speech perception with basic speech audiometry. There was no difference between Cases and Controls in speech perception neither in quiet nor with both speech and background noise from the front, although the within-group variance was greater among Cases. Cases scored slightly worse with speech from front and noise from either side. Self-reported hearing loss (both hearing loss in general and specifically with background noise), and tinnitus were about three times more common among Cases compared with Controls.

CONCLUSIONS

Cisplatin causes high-frequency hearing loss, but speech perception tests performed both in quiet and in background noise 30 years post-treatment indicate that the clinical relevance is limited for most patients. Few patients develop severe hearing loss that requires rehabilitation but it is important to identify these patients. Self-reported hearing loss and tinnitus were more common among Cases compared with Controls.

Changes in Vestibular Function in Patients With Head-and-Neck Cancer Undergoing Chemoradiation

INTRODUCTION

While the cochleotoxicity of cisplatin has been well investigated, less is known about the effects of platinum-based chemotherapy on the vestibular system. In particular, there is a lack of prospective studies using modern laboratory vestibular testing that examine the effects of cisplatin on the semicircular canals and on the otolith organs. The aim of the present study was, therefore, to investigate the vestibulotoxic effect of cisplatin in patients with head and neck tumors who are undergoing chemoradiation.

METHODS

Forty-five patients undergoing cisplatin-based chemoradiation for head and neck cancer received a vestibular assessment consisting of anamnesis, a horizontal video head impulse test (vHIT), ocular and cervical vestibular evoked myogenic potential testing, as well as pure tone audiometry. This assessment was performed before therapy, 6 weeks after therapy, and 3 months after therapy.

RESULTS

Video head impulse test showed a significantly reduced median gain 6 weeks after chemoradiation. In addition, significantly more refixational saccades could be detected after therapy. Vestibular evoked myogenic potential testing results also revealed significant changes, whereas pure tone audiometry did not. None of the patients mentioned "dizziness" during the follow-up examinations.

CONCLUSION

We demonstrated a vestibulotoxic effect of cisplatin-based chemoradiation in patients with head and neck cancer. Future studies are needed to better understand cisplatin-induced vestibulotoxicity and to identify possible vestibuloprotective substances. Still, before and after chemoradiation, patients should undergo not only auditory testing but also vestibular testing in order to detect potential vestibular loss as soon as possible and to quickly initiate vestibular physiotherapy.

Association of Hearing Impairment With Neurocognition in Survivors of Childhood Cancer

Importance

Despite advancements in cancer therapy and supportive care, childhood cancer survivors remain at risk for chronic morbidities associated with disease and treatment, such as hearing impairment (HI) and neurocognitive deficits. This study, to our knowledge, is the first to objectively measure hearing and neurocognitive function in a large cohort of long-term survivors of childhood cancer stratified by treatment exposures.

Objective

To assess the association of HI with neurocognitive function and the factors in HI that mediate neurocognitive outcomes in survivors of childhood cancer.

Design, Setting, and Participants

Data analyzed in this cross-sectional study were collected for the period April 25, 2007, to June 30, 2017, from participants in the St. Jude Lifetime Cohort Study (SJLIFE), an ongoing study that quantifies the long-term health outcomes of survivors of childhood cancer. Participants included those treated at St. Jude Children's Research Hospital (Memphis, Tennessee) for childhood cancer who survived 5 or more years after their original diagnosis and who were eligible for audiologic and neurocognitive testing. Hearing outcomes were coded using the Chang Ototoxicity Grading Scale. Data analysis was performed from March 22, 2019, to March 5, 2020.

Main Outcomes and Measures

Hearing and neurocognitive function. Survivors were grouped by hearing sensitivity (normal hearing [Chang grade 0], mild HI [Chang grades 1a, 1b, and 2a], or severe HI [Chang grade ≥2b]) and stratified by treatment exposure (platinum-only exposure group [treated with cisplatin and/or carboplatin chemotherapy], cochlear radiotherapy [RT] exposure group [treated with cochlear RT with or without platinum-based chemotherapy], or no exposure group [no platinum-based chemotherapy or cochlear RT]). Multivariable log-binomial models were adjusted for age at diagnosis, time since diagnosis, sex, and relevant treatment exposures.

Results

A total of 1520 survivors of childhood cancer were analyzed, among whom 814 were male survivors (53.6%), the median (interquartile range [IQR]) age was 29.4 (7.4-64.7) years, and the median (IQR) time since diagnosis was 20.4 (6.1-53.8) years. Prevalence and risk of severe HI among survivors were higher in survivors in the platinum-only (n = 107 [34.9%]; relative risk [RR], 1.68 [95% CI, 1.20-2.37]) or cochlear RT (n = 181 [38.3%]; RR, 2.69 [95% CI, 2.02-3.57) exposure group compared with those in the no exposure group (n = 65 [8.8%]). Severe HI was associated with deficits in verbal reasoning skills (no exposure group RR, 1.11 [95% CI, 0.50-2.43]; platinum-only exposure group RR, 1.93 [95% CI, 1.21-3.08]; cochlear RT exposure group RR, 2.00 [95% CI, 1.46-2.75]), verbal fluency (no exposure group RR, 1.86 [95% CI, 1.19-2.91]; platinum-only exposure group RR, 1.83 [95% CI, 1.24-2.71]; cochlear RT exposure group RR, 1.45 [95% CI, 1.09-1.94]), visuomotor speed (no exposure group RR, 1.87 [95% CI, 1.07-3.25]; platinum-only exposure group RR, 3.10 [95% CI, 1.92-4.99]; cochlear RT exposure group RR, 1.40 [95% CI, 1.11-1.78]), and mathematics skills (no exposure group RR, 1.90 [95% CI, 1.18-3.04]; platinum-only exposure group RR, 1.63 [95% CI, 1.05-2.53]; cochlear RT exposure group RR, 1.58 [95% CI, 1.15-2.18]), compared with survivors with normal hearing or with mild HI.

Conclusions and Relevance

Results of this study suggest that severe HI in childhood cancer survivors is associated with neurocognitive deficits independent of the neurotoxic treatment received. Early screening and intervention for HI may facilitate the development and maintenance of neurocognitive function and identify individuals at risk for impairment.

Ototoxicity and Platinum Uptake Following Cyclic Administration of Platinum-Based Chemotherapeutic Agents

Cisplatin is a widely used anti-cancer drug used to treat a variety of cancer types. One of the side effects of this life-saving drug is irreversible ototoxicity, resulting in permanent hearing loss in many patients. In order to understand why cisplatin is particularly toxic to the inner ear, we compared the hearing loss and cochlear uptake of cisplatin to that of two related drugs, carboplatin and oxaliplatin. These three drugs are similar in that each contains a core platinum atom; however, carboplatin and oxaliplatin are considered less ototoxic than cisplatin. We delivered these three drugs to mice using a 6-week cyclic drug administration protocol. We performed the experiment twice, once using equimolar concentrations of the drugs and once using concentrations of the drugs more proportional to those used in the clinic. For both concentrations, we detected a significant hearing loss caused by cisplatin and no hearing loss caused by carboplatin or oxaliplatin. Cochlear uptake of each drug was measured using inductively coupled plasma mass spectrometry (ICP-MS) to detect platinum. Cochlear platinum levels were highest in mice treated with cisplatin followed by oxaliplatin, while carboplatin was largely excluded from the cochlea. Even when the drug doses were increased, cochlear platinum remained low in mice treated with oxaliplatin or carboplatin. We also examined drug clearance from the inner ear by measuring platinum levels at 1 h and 24 h after drug administration. Our findings suggest that the reduced cochlear platinum we observed with oxaliplatin and carboplatin were not due to increased clearance of these drugs relative to cisplatin. Taken together, our data indicate that the differential ototoxicity among cisplatin, carboplatin, and oxaliplatin is attributable to differences in cochlear uptake of these three drugs.

Audiovestibular clinician experiences and opinions about cisplatin vestibulotoxicity

Purpose

Vestibulotoxicity associated with cisplatin chemotherapy is known to exist, but the extent, severity, and impact is unclear from the literature. This study explored knowledge, experiences, and opinions of audiovestibular professionals about cisplatin vestibulotoxicity.

Methods

An online survey was disseminated to clinicians working in the audiovestibular field.

Results

Ninety-three respondents participated in the survey. Most professionals were aware of potential vestibulotoxicity associated with cisplatin chemotherapy. Thirty-three percent of the respondents reported that they had seen patients with cisplatin vestibulotoxicity. Forty percent of them were confident in making the diagnosis and in managing the patient in this situation. The prevalence and impact of vestibulotoxicity including practicality of the assessment should be considered when designing an effective vestibulotoxicity screening protocol.

Conclusion

This study provides a better understanding of cisplatin vestibulotoxicity from the perspectives of audiovestibular clinicians, which will underpin appropriate detection and management of the condition.

Clinical trials evaluating transtympanic otoprotectants for cisplatin-induced ototoxicity: what do we know so far?

BACKGROUND

Cisplatin (CDDP) chemotherapy can cause serious side effects including irreversible and progressive hearing loss. Studies have aimed to assess potential protective strategies; however, systemic treatments have presented variable results, and potential interactions with CDDP have limited clinical trials.

METHODS

A review of the literature was performed in order to evaluate clinical trials that have studied a transtympanic approach as an otoprotectant strategy.

RESULTS

Six clinical trials were included. While a transtympanic approach can limit side effects and avoid interactions with CDDP, recurrent issues have been expressed including which otoprotectant to test, time delays between CDDP treatment and transtympanic injections, side effects such as pain and dizziness, concentrations, and number of injections. Clinical trials have used sodium thiosulfate, N-acetylcysteine and dexamethasone.

CONCLUSIONS

While a transtympanic approach seems like an attractive strategy, further research is needed to clarify which is the optimal otoprotectant, its dosage, and the number of injections.

Ototoxicity after platinum-based chemotherapy in the treatment of melanotic neuroectodermal tumour of infancy

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare infantile tumor that originates from mesenchymal-neuroectodermal cells, the treatment of which uses platinum derivatives that can affect hearing loss. The present study evaluated the long-term effects of ototoxicity following chemotherapy with cisplatin, vincristine, cyclophosphamide, teniposide and adriamycin in a 10-year-old patient after surgical removal of a MNTI tumor at the age of 8 months. Audiometric tests (high-frequency tonal audiometry, speech audiometry, speech acoustics, tympanometry and absorbance measurements) were performed during a 10-year follow-up after receiving chemotherapy. Hearing disorders in the high-frequency range (6,000 to 16,000 Hz range) were demonstrated for both ears, indicating that these may be the long-term effects of chemotherapy with use of platinum compounds during the treatment of infants.

The Relationship Between Cisplatin-related and Age-related Hearing Loss During an Extended Follow-up

OBJECTIVES

Cisplatin-related hearing loss (HL) is claimed to progress after treatment. This controlled longitudinal study with extended follow-up investigates HL in testicular cancer survivors (TCSs) after cisplatin-based chemotherapy (CBCT).

STUDY DESIGN

Controlled longitudinal study.

METHODS

Eighty-two TCSs treated with CBCT between 1980 and 1994 in Norway participated in two surveys (S1/S3), including pure-tone audiograms (0.125-8 kHz) and self-reported HL, 12 and 31 years after treatment, respectively. Hearing thresholds were age-adjusted based on age-matched hearing thresholds from the general population (controls). Hearing loss was defined as thresholds >20 dB at any frequency.

RESULTS

Between the two surveys, the prevalence of high-frequency HL (4, 6, and 8 kHz) increased from 73% to 94% but approached those of the aging general population after age adjustment. In TCSs aged >40 years at first survey, HL at the subsequent survey equaled that of controls. Self-reported HL increased from seven (9%) at S1 to 20 (26%) at S3. At S1, age-adjusted HL was identified in all (seven) TCSs reporting decreased hearing whereas at S3, hearing thresholds did not differ from controls in seven out of 20 patients reporting HL.

CONCLUSION

CBCT-related ototoxicity causes high-frequency HL, but in contrast to reports from follow-up studies from the first post-treatment decade, no major progression was found beyond the first post-treatment decade for frequencies 0.125-8 kHz. Importantly, with extended follow-up, hearing thresholds of patients approach those of the general population, possibly due to a less-than-additive effect with age-related hearing loss (ARHL) in CBCT-treated patients. Age-and sex-matching is strongly advised in long-term follow-up of CBCT-related ototoxicity. Specificity for detecting ototoxicity with self-reported questionnaires decreases with extended follow-up.

LEVEL OF EVIDENCE

3 Laryngoscope, 130:E515-E523, 2020.

Prevention of cisplatin-induced ototoxicity in children and adolescents with cancer: a clinical practice guideline

Despite ototoxicity being a prevalent consequence of cisplatin chemotherapy, little guidance exists on interventions to prevent this permanent and progressive adverse event. To develop a clinical practice guideline for the prevention of cisplatin-induced ototoxicity in children and adolescents with cancer, we convened an international, multidisciplinary panel of experts and patient advocates to update a systematic review of randomised trials for the prevention of cisplatin-induced ototoxicity. The systematic review identified 27 eligible adult and paediatric trials that evaluated amifostine, sodium diethyldithiocarbamate or disulfiram, systemic sodium thiosulfate, intratympanic therapies, and cisplatin infusion duration. Regarding systemic sodium thiosulfate, the panel made a strong recommendation for administration in non-metastatic hepatoblastoma, a weak recommendation for administration in other non-metastatic cancers, and a weak recommendation against its routine use in metastatic cancers. Amifostine, sodium diethyldithiocarbamate, and intratympanic therapy should not be routinely used. Cisplatin infusion duration should not be altered as a means to reduce ototoxicity. Further research to determine the safety of sodium thiosulfate in patients with metastatic cancer is encouraged.

Looking beyond the audiogram in ototoxicity associated with platinum-based chemotherapy

Introduction

Ototoxicity associated with platinum-based chemotherapy is highly prevalent and can cause detrimental consequences among cancer survivors.

Discussion

In this article, we highlight important aspects of the evaluation of ototoxicity with the aim to increase awareness of Oncologists in this regard. Standard pure tone audiometry alone is inadequate for this context. Comprehensive and consistent hearing tests should be implemented in a monitoring and surveillance program. High-frequency audiometry (10–16 kHz) is a sensitive tool in the detection of ototoxic hearing loss at onset. In addition to threshold audiometry, measures of speech comprehension (both in quiet and in noise) can add useful information in the evaluation of hearing in real-life situations. Not only hearing loss, but also tinnitus and imbalance are common in patients who receive platinum-based chemotherapy, and can cause debilitating effects upon quality of life in this population. Moreover, self-report measures associated with cochlear and vestibular handicaps can provide valuable information regarding the impact of ototoxicity.

Conclusions

It is vital to build awareness about the variety and impact of the symptoms of ototoxicity. Comprehensive evaluation of hearing status along with self-reported impact of the cochlear and vestibular handicap should be implemented in a monitoring and surveillance program for appropriate investigation and management.

Are There Cochlear Dead Regions Involved in Hearing Loss after Cisplatin Ototoxicity?

BACKGROUND

The most common complaint of patients affected by chemotherapy-induced hearing loss is difficulty understanding speech in noisy environments despite the use of hearing aids. Cochlear dead regions, those areas with damaged or absent inner hair cells and dendrites, may account for this type of hearing loss. However, it is unknown whether this condition is associated with cisplatin agents.

OBJECTIVE

The aim of this study was to determine whether cisplatin is associated with hearing loss and cochlear dead regions.

METHODS

This prospective cross-sectional study was conducted in patients participating in routine audiological monitoring during and after chemotherapy treatment. Adults undergoing audiological evaluation who had completed chemotherapy treatment were invited to participate. Patients were divided into 3 groups according to pure tone thresholds. Group 1 patients had thresholds over 70 dB (HL) at 2,000 Hz and higher frequencies. Group 2 patients had thresholds below 70 dB (HL) up to 2,000 Hz. Patients in the control group had normal thresholds at all frequencies. The threshold equalizing noise test (TEN[HL]) was used to identify cochlear dead regions by repeating thresholds in the presence of TEN noise played from a compact disc. The presence of cochlear dead regions was established when the masked threshold was 10 dB or greater above the TEN level and 10 dB or greater above the absolute threshold at any frequency.

RESULTS

Twelve patients were included in study group 1, 10 patients in study group 2, and 7 patients in the control group. Cochlear dead regions were present in all patients with hearing loss and in none of the control group. For groups 1 and 2, mean differences between absolute and masked thresholds were 21 and 16 dB at 500 Hz; 22 and 15 dB at 1,000 Hz; 31 and 17 dB at 2,000 Hz; 32 and 20 dB at 3,000 Hz; and 31 and 21 dB at 4,000 Hz, respectively. Nevertheless, analysis of variance testing with Bonferroni analysis showed a difference between groups 1 and 2 only at 2,000, 3,000, and 4,000 Hz.

CONCLUSION

We found unresponsive or dead cochlear regions in patients who had undergone cisplatin chemotherapy even among patients with mild to moderate hearing loss.

Interventions for cisplatin-induced hearing loss in children and adolescents with cancer

The identification of preventive interventions that are safe and effective for cisplatin-induced ototoxicity is important, especially in children because hearing loss can impair speech-language acquisition development. Previous randomised trials assessed systemic drugs such as amifostine, sodium diethyldithiocarbamate or disulfiram, and sodium thiosulfate. Amifostine, sodium diethyldithiocarbamate, and disulfiram did not show hearing preservation. Paediatric trials assessing sodium thiosulfate showed efficacy in terms of hearing protection. The SIOPEL 6 trial consisted solely of patients with localised hepatoblastoma and no effects on survival were shown. In the ACCL0431 trial, which included heterogeneous patients, a post-hoc analysis showed significantly worse overall survival among patients who had disseminated disease receiving sodium thiosulfate than among controls, but not among those with localised disease. Intratympanically administered drugs have mainly been assessed in adults and include N-acetylcysteine and dexamethasone. Inconsistent effects of these drugs were identified but these studies were limited by design, small sample size, and statistical approach. Future studies of systemic drugs will need to consider the measurement of disease outcomes through study design and sample size, and ototoxicity endpoints should be harmonised to enhance comparability between trials.

An optimized, clinically relevant mouse model of cisplatin-induced ototoxicity

Cisplatin-induced ototoxicity results in significant, permanent hearing loss in pediatric and adult cancer survivors. Elucidating the mechanisms underlying cisplatin-induced hearing loss as well as the development of therapies to reduce and/or reverse cisplatin ototoxicity have been impeded by suboptimal animal models. Clinically, cisplatin is most commonly administered in multi-dose, multi-cycle protocols. However, many animal studies are conducted using single injections of high-dose cisplatin, which is not reflective of clinical cisplatin administration protocols. Significant limitations of both high-dose, single-injection protocols and previous multi-dose protocols in rodent models include high mortality rates and relatively small changes in hearing sensitivity. These limitations restrict assessment of both long-term changes in hearing sensitivity and effects of potential protective therapies. Here, we present a detailed method for an optimized mouse model of cisplatin ototoxicity that utilizes a multi-cycle administration protocol that better approximates the type and degree of hearing loss observed clinically. This protocol results in significant hearing loss with very low mortality. This mouse model of cisplatin ototoxicity provides a platform for examining mechanisms of cisplatin-induced hearing loss as well as developing therapies to protect the hearing of cancer patients receiving cisplatin therapy.

Vestibulotoxicity Associated With Platinum-Based Chemotherapy in Survivors of Cancer: A Scoping Review

Background: Cochleotoxicity following the treatment with platinum-based chemotherapy is well documented. The potential for vestibulotoxicity is still unclear. This scoping review examined the extent of current research literature, summarized research findings and identified research gaps regarding vestibular-related adverse effects associated with platinum-based chemotherapy in survivors of cancer.

Methods: Inclusion criteria followed the PICO principles: Participants, adult, and pediatric cancer patients of any cancer type; Intervention, platinum-based chemotherapy (such as cisplatin, carboplatin, and oxaliplatin); Control, none or any; Outcomes, vestibular-related adverse effects. English language articles published since 1978 were retrieved. Seventy-five eligible studies were identified from a systematic literature search, and relevant data were charted, collated, and summarized.

Results: Testing for vestibulotoxicity predominately featured functional evaluation of the horizontal semicircular canal using the caloric and rotational tests. The rate of abnormal vestibular function test results after chemotherapy administration varied from 0 to 50%. The results of objective testing did not always correspond to patient symptoms. There is tentative support for patients with pre-existing loss of vestibular function to be more likely to experience vestibular toxicity after dosing with cisplatin.

Conclusions: A number of studies reported significant evidence of vestibular toxicities associated with platinum-based chemotherapy, especially cisplatin. This scoping review emphasizes that vestibular toxicity needs more attention and comprehensive evaluation. Specifically, studies that analyse cumulative dose of platinum-based chemotherapy, affected sites of lesion in vestibular end organs, and the correlation and temporal patterns of cochlear and vestibular toxicity are needed.