Evaluation and Management of Hearing Loss in Survivors of Childhood and Adolescent Cancers: A Report From the Children's Oncology Group

Subjective and Objective Hearing Loss Among US Adult Cancer Survivors

Importance

Cancer survivors are at a higher risk of developing hearing loss (HL) due to older age, chemotherapy, and radiotherapy. However, the prevalence of HL among US cancer survivors remains unknown. Additionally, there is a lack of uniform HL screening guidelines for this enlarging population.

Objective

To estimate the prevalence of subjective HL and objective HL by audiometry test among cancer survivors and compare them with the general population as well as to assess the performance of subjective HL questions in detecting true (ie, audiometry-confirmed) HL.

Design, Setting, and Participants

In a cross-sectional design, adults between ages 20 and 80 years who had audiometry testing and responded to a hearing questionnaire from the National Health and Nutrition Examination Survey (2011-2012, 2015-2016, and 2017 to March 2020 prepandemic survey cycles) were selected. Data analysis was conducted from August 13, 2022, to July 26, 2023.

Main Outcomes and Measures

The weighted prevalence of subjective HL (troublesome hearing and tinnitus) and objective HL (speech-frequency HL and high-frequency HL) by audiometry were calculated. Analyses with χ2 testing and multiadjusted logistic regression models were used to compare HL between cancer survivors and the general population. To evaluate the performance of subjective HL questions as a tool to screen for objective HL by audiometry, areas under the curve were estimated using age- and gender-adjusted logistic regression.

Results

Among the total 9337 participants (weighted n = 90 098 441; 51.2% women), 10.3% were cancer survivors. Compared with the general population, cancer survivors had a higher prevalence of troublesome hearing (adjusted odds ratio [AOR], 1.43; 95% CI, 1.11-1.84), tinnitus (AOR, 1.28; 95% CI, 0.94-1.74), speech-frequency HL (AOR, 1.43; 95% CI, 1.11-1.85), and high-frequency HL (AOR, 1.74; 95% CI, 1.29-2.34). When using the subjective HL tool and questioning regarding whether the participants were having troublesome hearing and/or tinnitus in screening for HL, the age- and gender-adjusted area under the curve was 0.88 in detecting speech-frequency HL and 0.90 in detecting high-frequency HL.

Conclusion and Relevance

The findings of this study suggest that cancer survivors have a significantly higher prevalence of HL than the general population. Two subjective HL questions could potentially accurately identify those who have true HL and provide a simple and efficient screening tool for health care professionals. Cancer survivors and their families should be educated and encouraged to discuss hearing concerns, and health care professionals should facilitate raising awareness and provide early screening and timely referral when HL is identified.

Improving quality and quantity of life for childhood cancer survivors globally in the twenty-first century

The contributions of cooperative groups to performing large-cohort clinical trials and long-term survivorship studies have facilitated advances in treatment, supportive care and, ultimately, survival for patients with paediatric cancers. As a result, the number of childhood cancer survivors in the USA alone is expected to reach almost 580,000 by 2040. Despite these substantial improvements, childhood cancer survivors continue to have an elevated burden of chronic disease and an excess risk of early death compared with the general population and therefore constitute a large, medically vulnerable population for which delivery of high-quality, personalized care is much needed. Data from large survivorship cohorts have enabled the identification of compelling associations between paediatric cancers, cancer therapy and long-term health conditions. Effectively translating these findings into clinical care that improves the quality and quantity of life for survivors remains an important focus of ongoing research. Continued development of well-designed clinical studies incorporating dissemination and implementation strategies with input from patient advocates and other key stakeholders is crucial to overcoming these gaps. This Review highlights the global progress made and future efforts that will be needed to further increase the quality and quantity of life-years gained for childhood cancer survivors.

Communication, academic and social outcomes of childhood cancer survivors with hearing loss: A systematic review

Many children treated for cancer are at risk of hearing loss. However, little is known about how hearing loss impacts their communication, academic and social outcomes. To examine the impact, this systematic review aimed to synthesise and appraise quantitative and qualitative studies reporting on (i) participants with hearing loss treated with platinum-based chemotherapy or cranial radiotherapy during childhood; and (ii) speech, language, academic performance, or social participation findings. Systematic database searches yielded 23 relevant articles that were analysed using narrative synthesis. Difficulties were reported for some but not all communication, academic and social aspects; however, a quality assessment using Grading of Recommendations Assessment, Development and Evaluation (GRADE) revealed low to very low certainty in the findings. Future research should aim to increase the quality of the research evidence and explore how multidisciplinary services can provide evidence-based support for childhood cancer survivors with competing hearing, communication, and social difficulties.

Neurocognition and mean radiotherapy dose to vulnerable brain structures: new organs at risk?

BACKGROUND

Children with brain tumors are at high risk of neurocognitive decline after radiotherapy (RT). However, there is a lack of studies on how RT doses to organs at risk (OARs) impacts neurocognition. The aim of this study was to examine dose-risk relationships for mean RT dose to different brain structures important for neurocognitive networks. We explored previously established OARs and potentially new OARs.

METHODS

A sample of 44 pediatric brain tumor survivors who had received proton and/or photon RT were included. Correlations between mean RT doses to OARs and IQ were analyzed. Previously established OARs were cochleae, optic chiasm, optic nerve, pituitary gland, hypothalamus, hippocampus and pons. Potential new OARs for RT-induced neurocognitive decline were cerebellum, vermis and thalamus.

RESULTS

Mean RT dose to different OARs correlated with several IQ subtests. Higher mean RT dose to cochleae, optic nerve, cerebellum, vermis and pons was correlated with lower performance on particularly full-scale IQ (FIQ), Perceptual Reasoning (PRI), Working Memory (WMI) and Processing Speed Index (PSI). Higher mean RT dose to hippocampus correlated with lower performance on processing speed and working memory. For those receiving whole brain RT (WBRT), higher mean RT dose to the pituitary gland correlated with lower performance on working memory.

CONCLUSION

A high dose-risk correlation was found between IQ subtests and mean RT dose in established and potential new OARs. Thus, in the lack of validated dose constraints for vulnerable brain structures, a parsimonious approach in RT planning should be considered to preserve neurocognitive networks.

Cisplatin in Liver Cancer Therapy

Hepatocellular carcinoma (HCC) is the most common primary liver tumor and is often diagnosed at an unresectable advanced stage. Systemic chemotherapy as well as transarterial chemoembolization (TACE) and hepatic arterial infusion chemotherapy (HAIC) are used to treat advanced HCC. TACE and HAIC have long been the standard of care for patients with unresectable HCC but are limited to the treatment of intrahepatic lesions. Systemic chemotherapy with doxorubicin or chemohormonal therapy with tamoxifen have also been considered, but neither has demonstrated survival benefits. In the treatment of unresectable advanced HCC, cisplatin is administered transhepatic arterially for local treatment. Subsequently, for cisplatin-refractory cases due to drug resistance, a shift to systemic therapy with a different mechanism of action is expected to produce new antitumor effects. Cisplatin is also used for the treatment of liver tumors other than HCC. This review summarizes the action and resistance mechanism of cisplatin and describes the treatment of the major hepatobiliary cancers for which cisplatin is used as an anticancer agent, with a focus on HCC.

The Health Care Utilization and Medical Costs in Long-Term Follow-Up of Children Diagnosed With Leukemia, Solid Tumor, or Brain Tumor: Population-Based Study Using the National Health Insurance Claims Data

BACKGROUND

Childhood cancer survivors are at a high risk of medical consequences of their disease and treatment. There is growing information about the long-term health issues of childhood cancer survivors; however, there are very few studies describing the health care utilization and costs for this unique population. Understanding their utilization of health care services and costs will provide the basis for developing strategies to better serve these individuals and potentially reduce the cost.

OBJECTIVE

This study aims to determine the utilization of health services and costs for long-term survivors of childhood cancer in Taiwan.

METHODS

This is a nationwide, population-based, retrospective case-control study. We analyzed the claims data of the National Health Insurance that covers 99% of the Taiwanese population of 25.68 million. A total of 33,105 children had survived for at least 5 years after the first appearance of a diagnostic code of cancer or a benign brain tumor before the age of 18 years from 2000 to 2010 with follow-up to 2015. An age- and gender-matched control group of 64,754 individuals with no cancer was randomly selected for comparison. Utilization was compared between the cancer and no cancer groups by χ2 test. The annual medical expense was compared by the Mann-Whitney U test and Kruskal-Wallis rank-sum test.

RESULTS

At a median follow-up of 7 years, childhood cancer survivors utilized a significantly higher proportion of medical center, regional hospital, inpatient, and emergency services in contrast to no cancer individuals: 57.92% (19,174/33,105) versus 44.51% (28,825/64,754), 90.66% (30,014/33,105) versus 85.70% (55,493/64,754), 27.19% (9000/33,105) versus 20.31% (13,152/64,754), and 65.26% (21,604/33,105) versus 59.36% (38,441/64,754), respectively (all P<.001). The annual total expense (median, interquartile range) of childhood cancer survivors was significantly higher than that of the comparison group (US $285.56, US $161.78-US $535.80 per year vs US $203.90, US $118.98-US $347.55 per year; P<.001). Survivors with female gender, diagnosis before the age of 3 years, and diagnosis of brain cancer or a benign brain tumor had significantly higher annual outpatient expenses (all P<.001). Moreover, the analysis of outpatient medication costs showed that hormonal and neurological medications comprised the 2 largest costs in brain cancer and benign brain tumor survivors.

CONCLUSIONS

Survivors of childhood cancer and a benign brain tumor had higher utilization of advanced health resources and higher costs of care. The design of the initial treatment plan minimizing long-term consequences, early intervention strategies, and survivorship programs have the potential to mitigate costs of late effects due to childhood cancer and its treatment.

A Systematic Review of Host Genomic Variation and Neuropsychological Outcomes for Pediatric Cancer Survivors

Pediatric survivors of brain tumors and acute lymphoblastic leukemia (ALL) are at risk for long-term deficits in their neuropsychological functioning. Researchers have begun examining associations between germline single nucleotide polymorphisms (SNPs), which interact with cancer treatment, and neuropsychological outcomes. This review synthesizes the impact of treatment-related toxicity from germline SNPs by neuropsychological domain (i.e., working memory, processing speed, psychological functioning) in pediatric survivors. By focusing on specific neuropsychological domains, this review will examine outcome measurement and critique methodology. Fourteen studies were identified and included in this review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). All studies were published in peer-reviewed journals in English by November 24^th, 2021. Reviewed studies were not of sufficient quality for a meta-analysis due to varying measurement strategies, gaps in reported descriptive variables, and low power. All neuropsychological domains evaluated in this review had associations with SNPs, except fine motor and visual integration abilities. Only five SNPs had consistent neuropsychological findings in more than one study or cohort. Future research and replication studies should use validated measures of discrete skills that are central to empirically validated models of survivors' long-term outcomes (i.e., attention, working memory, processing speed). Researchers should examine SNPs across pathophysiological pathways to investigate additive genetic risk in pediatric cancer survivors. Two SNPs were identified that confer resiliency in neuropsychological functioning, and future work should investigate resiliency genotypes and their underlying biological mechanisms.

Protective Effect of Avenanthramide-C on Auditory Hair Cells against Oxidative Stress, Inflammatory Cytokines, and DNA Damage in Cisplatin-Induced Ototoxicity

Cisplatin-induced ototoxicity leads to hearing impairment, possibly through reactive oxygen species (ROS) production and DNA damage in cochlear hair cells (HC), although the exact mechanism is unknown. Avenanthramide-C (AVN-C), a natural, potent antioxidant, was evaluated in three study groups of normal adult C57Bl/6 mice (control, cisplatin, and AVN-C+cisplatin) for the prevention of cisplatin-induced hearing loss. Auditory brainstem responses and immunohistochemistry of outer hair cells (OHCs) were ascertained. Cell survival, ROS production, Phospho-H2AX-enabled tracking of DNA damage-repair kinetics, and expression levels of inflammatory cytokines (TNF-α, IL-1β, IL6, iNOS, and COX2) were assessed using House Ear Institute-Organ of Corti 1 (HEI-OC1 Cells). In the in vivo mouse model, following cisplatin-induced damage, AVN-C decreased the hearing thresholds and sheltered all cochlear turns' OHCs. In HEI-OC1 cells, AVN-C preserved cell viability and decreased ROS production, whereas cisplatin enhanced both ROS levels and cell viability. In HEI-OC1 cells, AVN-C downregulated IL6, IL-1β, TNF-α, iNOS, and COX2 production that was upregulated by cisplatin treatment. AVN-C attenuated the cisplatin-enhanced nuclear H2AX activation. AVN-C had a strong protective effect against cisplatin-induced ototoxicity through inhibition of ROS and inflammatory cytokine production and DNA damage and is thus a promising candidate for preventing cisplatin-induced sensorineural hearing loss.

Early and Long-Term Ototoxicity Noted in Children Due to Platinum Compounds: Prevalence and Risk Factors

BACKGROUND

Platinum compounds are a group of fundamental chemotherapeutics used in the treatment of solid tumors, but they are burdened by side effects, such as ototoxicity. The objective of this study was to evaluate the incidence of ototoxicity caused by platinum compounds and the risk factors affecting its appearance/progression.

METHODS

Data from 53 patients who received platinum compounds and who had been off therapy for at least 5 years were analyzed. We collected data relating to audiometry conducted annually from the end of treatment and for at least 5 subsequent years, as well as information concerning the oncological history and comorbidities.

RESULTS

At the end of the treatment, 17 patients (32.08%) presented ototoxicity, according to the Boston SIOP Ototoxicity Scale; the risk factors included a higher serum creatinine value at diagnosis, having undergone cranial radiotherapy, and needing magnesium supplementation. After 5 years from the end of the treatment, the number of patients with exhibiting ototoxicity was 31 (58.5%); the factors that influenced the onset/progression of the damage were having undergone radiotherapy (HR 1.23; p < 0.01) and having received therapy with aminoglycosides (HR 1.27; p < 0.01).

CONCLUSIONS

Ototoxicity caused by platinum compounds can occur even after the conclusion of the treatments, and the factors affecting its progression are radiotherapy and the aminoglycosides therapy.

Ototoxicity After Cisplatin-Based Chemotherapy: Factors Associated With Discrepancies Between Patient-Reported Outcomes and Audiometric Assessments

OBJECTIVES

To provide new information on factors associated with discrepancies between patient-reported and audiometrically defined hearing loss (HL) in adult-onset cancer survivors after cisplatin-based chemotherapy (CBCT) and to comprehensively investigate risk factors associated with audiometrically defined HL.

DESIGN

A total of 1410 testicular cancer survivors (TCS) ≥6 months post-CBCT underwent comprehensive audiometric assessments (0.25 to 12 kHz) and completed questionnaires. HL severity was defined using American Speech-Language-Hearing Association criteria. Multivariable multinomial regression identified factors associated with discrepancies between patient-reported and audiometrically defined HL and multivariable ordinal regression evaluated factors associated with the latter.

RESULTS

Overall, 34.8% of TCS self-reported HL. Among TCS without tinnitus, those with audiometrically defined HL at only extended high frequencies (EHFs) (10 to 12 kHz) (17.8%) or at both EHFs and standard frequencies (0.25 to 8 kHz) (23.4%) were significantly more likely to self-report HL than those with no audiometrically defined HL (8.1%) [odds ratio (OR) = 2.48; 95% confidence interval (CI), 1.31 to 4.68; and OR = 3.49; 95% CI, 1.89 to 6.44, respectively]. Older age (OR = 1.09; 95% CI, 1.07 to 1.11, p < 0.0001), absence of prior noise exposure (OR = 1.40; 95% CI, 1.06 to 1.84, p = 0.02), mixed/conductive HL (OR = 2.01; 95% CI, 1.34 to 3.02, p = 0.0007), no hearing aid use (OR = 5.64; 95% CI, 1.84 to 17.32, p = 0.003), and lower education (OR = 2.12; 95% CI, 1.23 to 3.67, p = 0.007 for high school or less education versus postgraduate education) were associated with greater underestimation of audiometrically defined HL severity, while tinnitus was associated with greater overestimation (OR = 4.65; 95% CI, 2.64 to 8.20 for a little tinnitus, OR = 5.87; 95% CI, 2.65 to 13.04 for quite a bit tinnitus, and OR = 10.57; 95% CI, 4.91 to 22.79 for very much tinnitus p < 0.0001). Older age (OR = 1.13; 95% CI, 1.12 to 1.15, p < 0.0001), cumulative cisplatin dose (>300 mg/m2, OR = 1.47; 95% CI, 1.21 to 1.80, p = 0.0001), and hypertension (OR = 1.80; 95% CI, 1.28 to 2.52, p = 0.0007) were associated with greater American Speech-Language-Hearing Association-defined HL severity, whereas postgraduate education (OR = 0.58; 95% CI, 0.40 to 0.85, p = 0.005) was associated with less severe HL.

CONCLUSIONS

Discrepancies between patient-reported and audiometrically defined HL after CBCT are due to several factors. For survivors who self-report HL but have normal audiometric findings at standard frequencies, referral to an audiologist for additional testing and inclusion of EHFs in audiometric assessments should be considered.

Childhood Cancer Survivors and Distance Education Challenges: Lessons Learned From the COVID-19 Pandemic

OBJECTIVE

Pediatric cancer survivors have historically struggled to receive adequate educational supports. In Spring 2020, the COVID-19 pandemic forced an emergency switch from traditional in-person education models to distance education, but little information is available regarding experiences of pediatric survivors' coping with schooling since that time.

METHODS

This article presents exploratory mixed methods findings from a quality improvement project including qualitative interviews and a quantitative survey conducted with parents of pediatric oncology survivors identified through neuropsychological assessment, and the use of school-based services as having educationally relevant neurocognitive impacts of disease or treatment. The interviews explored experiences of education and instructional delivery during the COVID-19 school closures in spring of 2020 and the beginning of the 2020-2021 school year and served as the foundation for a quantitative survey to determine the generalizability of findings.

RESULTS

Qualitative interviews highlighted 3 emergent themes regarding the shared experiences of distance schooling for children with cancer during the COVID-19 school closures: (a) attention, (b) mental health, and (c) access to instruction. A follow-up quantitative survey supported the qualitative findings and their generalizability to the schooling experiences of other children with cancer during the pandemic.

CONCLUSION

This article describes and explores each theme and offers suggestions for pediatric supports and changes to provider service delivery (including weblinks to access project-developed resources) as a result of ongoing pandemic-related schooling needs.

Hearing loss and intellectual outcome in children treated for embryonal brain tumors: Implications for young children treated with radiation sparing approaches

Purpose

We investigate the impact of severe sensorineural hearing loss (SNHL) and for the first time evaluate the effect of unilateral versus bilateral SNHL on intellectual outcome in a cohort of children with embryonal brain tumors treated with and without radiation.

Methods

Data were from 94 childhood survivors of posterior fossa (PF) embryonal brain tumors who were treated with either: (1) chemotherapy alone (n = 16, 7.11 [3.41] years, 11M/5F), (2) standard‐dose craniospinal irradiation (CSI) and/or large boost volumes (n = 44, 13.05 [3.26] years, 29M/15F), or (3) reduced‐dose CSI with a boost restricted to the tumor bed (n = 34, 11.07 [3.80] years, 19M/15F). We compared intellectual outcome between children who: (1) did and did not develop SNHL and (2) developed unilateral versus bilateral SNHL. A Chang grade of ≥2b that required the use of a hearing aid was considered severe SNHL. Comparisons were made overall and within each treatment group separately.

Results

Patients who developed SNHL had lower full scale IQ (p = 0.007), verbal comprehension (p = 0.003), and working memory (p = 0.02) than patients without SNHL. No differences were observed between patients who had unilateral versus bilateral SNHL (all p > 0.05). Patients treated with chemotherapy alone who developed SNHL had lower mean working memory (p = 0.03) than patients who did not develop SNHL. Among patients treated with CSI, no IQ indices differed between those with and without SNHL (all p > 0.05).

Conclusions

Children treated for embryonal brain tumors who develop severe SNHL have lower intellectual outcome than patients with preserved hearing: this association is especially profound in young children treated with radiation sparing approaches. We also demonstrate that intellectual outcome is similarly impaired in patients who develop unilateral versus bilateral SNHL. These findings suggest that early intervention to preserve hearing is critical.

Hearing Loss Risk in Pediatric Patients Treated with Cranial Irradiation and Cisplatin-Based Chemotherapy

PURPOSE

Cranial radiation therapy (RT) and cisplatin-based chemotherapy are essential to treating many pediatric cancers but cause significant ototoxicity. The objective of this study is to determine the relationship between the RT dose and the risk of subsequent hearing loss in pediatric patients treated with cisplatin.

METHODS AND MATERIALS

This retrospective study of cisplatin-treated pediatric patients examined ototoxicity from cranial RT. Ototoxicity was graded for each ear according to the International Society of Pediatric Oncology (SIOP) consensus ototoxicity scale. The RT dose to the cochlea was calculated using the mean, median, maximum, and minimum dose received to determine the most predictive parameter for hearing loss. Multivariable logistic regression models then examined risk factors for hearing loss.

RESULTS

In 96 children (161 ears) treated with RT + cisplatin, the minimum cochlear RT dose was most predictive of hearing loss. A higher cochlear RT dose was associated with increased hearing loss (odds ratio per 10 Gy dose increase = 1.64; P = .043), with an added risk in those receiving an autologous bone marrow transplantation (hazard ratio = 10.47; P < .001).

CONCLUSIONS

This research supports further testing of the minimum cochlear RT dose as a more predictive dose parameter for risk of ototoxicity. The cochlear RT dose was additive to the risk of hearing loss from underlying cisplatin-based chemotherapy. Exposure to autologous bone marrow transplantation was the strongest predictor of developing hearing loss, placing these children at particularly high risk for hearing loss across all cochlear doses. Future prospective studies are crucial to further inform RT dose thresholds and minimize the risk of hearing loss in childhood cancer survivors.

Potential use of n-3 PUFAs to prevent oxidative stress-derived ototoxicity caused by platinum-based chemotherapy

Platinum-based compounds are widely used for the treatment of different malignancies due to their high effectiveness. Unfortunately, platinum-based treatment may lead to ototoxicity, an often-irreversible side effect without a known effective treatment and prevention plan. Platinum-based compound-related ototoxicity results mainly from the production of toxic levels of reactive oxygen species (ROS) rather than DNA-adduct formation, which has led to test strategies based on direct ROS scavengers to ameliorate hearing loss. However, favorable clinical results have been associated with several complications, including potential interactions with chemotherapy efficacy. To understand the contribution of the different cytotoxic mechanisms of platinum analogues on malignant cells and auditory cells, the particular susceptibility and response of both kinds of cells to molecules that potentially interfere with these mechanisms, is fundamental to develop innovative strategies to prevent ototoxicity without affecting antineoplastic effects. The n-3 long-chain polyunsaturated fatty acids (n-3 PUFAs) have been tried in different clinical settings, including with cancer patients. Nevertheless, their use to decrease cisplatin-induced ototoxicity has not been explored to date. In this hypothesis paper, we address the mechanisms of platinum compounds-derived ototoxicity, focusing on the differences between the effects of these compounds in neoplastic versus auditory cells. We discuss the basis for a strategic use of n-3 PUFAs to potentially protect auditory cells from platinum-derived injury without affecting neoplastic cells and chemotherapy efficacy.

Assessment and Management of Platinum-Related Ototoxicity in Children Treated for Cancer

Platinum compounds are a group of chemotherapeutic agents included in many pediatric and adult oncologic treatment protocols. The main platinum compounds are cisplatin, carboplatin, and oxaliplatin. Their use in clinical practice has greatly improved long-term survival of pediatric patients, but they also cause some toxic effects: ototoxicity, myelosuppression, nephrotoxicity, and neurotoxicity. Hearing damage is one of the main toxic effects of platinum compounds, and it derives from the degeneration of hair cells of the ear, which, not having self-renewal capacity, cannot reconstitute themselves. Hearing loss from platinum exposure is typically bilateral, sensorineural, and permanent, and it is caused by the same mechanisms with which platinum acts on neoplastic cells. According to available data from the literature, the optimal timing for the audiological test during and after treatment with platinum compounds is not well defined. Moreover, no substances capable of preventing the onset of hearing loss have been identified.

Prevalence of Ototoxicity Following Hematopoietic Stem Cell Transplantation in Pediatric Patients

The use of hematopoietic stem cell transplantation (HSCT) is increasing for a variety of diseases. Ototoxicity from this procedure has not been extensively studied. A retrospective chart review examined 275 patients from this institution who underwent HSCT between January 1, 2007, and April 30, 2017. Data extracted included therapy before HSCT and the subsequent course of transplantation. Evaluable patients had complete medical records and interpretable audiograms available. Ototoxicity constituted significant threshold changes from baseline or changes in International Society of Pediatric Oncology/Boston Ototoxicity Grading Scale (SIOP) grade comparing audiogram results just before HSCT with those following the transplantation procedure. A total of 147 patients were evaluable. Ototoxicity was observed in 10.2% of the patients. Higher SIOP grade before HSCT was significantly associated with a higher risk of post-transplantation ototoxicity (P < .01). Previous cisplatin treatment (P < .0001), but not carboplatin or radiation treatment, was also associated with ototoxicity. Patients with a solid tumor or brain tumor (P < .0001) and those who received an autologous transplant (P = .0002) were also at increased risk. No post-transplantation event was significantly associated with ototoxicity. Ototoxicity affects a significant percentage of patients undergoing HSCT, and careful monitoring is needed to identify patients impacted by this procedure.

Caring for survivors of childhood cancer: it takes a village

PURPOSE OF REVIEW

Over 80% of children diagnosed with cancer are now cured. The burgeoning population of survivors of childhood cancer experiences high rates of morbidity and mortality due to 'late-effects' of treatment. These can be defined as any consequence of treatment that persists beyond or develops after the completion of cancer therapy. Awareness of late-effects is critically important for pediatricians and adult providers alike, as late-effects impact children in proximity to cancer treatment, as well as adults many decades removed. This review presents the importance of lifelong follow-up care for survivors, highlights existing screening guidelines, and reviews various models of survivor care.

RECENT FINDINGS

National and international guidelines have been developed to standardize screening for survivors, and multiple models of survivorship care exist. The optimal model likely depends on individual factors, including the survivor's needs and preferences, as well as local resources. Key strategies for the successful care of survivors include accurate risk-stratification for specific late-effects, individualized screening plans, education of survivors and professionals, clear communication between providers, and well coordinated transition of care across services.

SUMMARY

Early identification and management of late-effects are important for survivors of childhood cancer. Providers should be familiar with the risks for specific late-effects and have access to screening guidelines. The strengths and weaknesses of care models, along with individual circumstances, should be considered in designing the optimal approach to care for each survivor.

Hearing Loss in Adult Survivors of Childhood Cancer Treated with Radiotherapy

The ototoxic effects of radiotherapy have been poorly characterized. We examined adult survivors of childhood cancer who were treated with radiotherapy, which included the head, before the age of 22 years and between 1952 and 2016. Those who received platinum chemotherapy were excluded. Demographic, diagnosis, and treatment outcomes were captured. Audiograms were graded using the Chang and International Society of Paediatric Oncology ototoxicity (SIOP) scales. Among 276 patients with a history of radiation to sites that included the brain, orbit, nasopharynx, and total body irradiation, the median age at treatment was 10.1 years and 59% were male. Of 51 survivors who had post-treatment audiograms, 19 demonstrated severe hearing impairment according to both the Chang and SIOP scales after a median follow-up of 16.6 years. Of those with severe impairment, 10 were using hearing aids. Among the 23 patients with more than one audiogram, five had normal hearing on the first audiogram but hearing loss upon subsequent study. Ototoxic effects of radiotherapy are present in a significant portion of survivors, but impairment may present over time, and our results suggest that many are not being screened. Further, among patients with severe hearing loss, use of hearing aids is not universal. Expansion of access to audiology testing and hearing interventions may be warranted.

Long-term auditory complications after childhood cancer: A report from the Swiss Childhood Cancer Survivor Study

BACKGROUND

Auditory complications are an adverse event of childhood cancer treatment, especially common in children treated with platinum chemotherapy or cranial radiation. Variation between diagnostic childhood cancer groups has rarely been studied, and we do not know if the burden of auditory complications has changed over the last decades.

PROCEDURE

Within the Swiss Childhood Cancer Survivor Study, we sent a questionnaire to all survivors who were diagnosed at age 16 years or less between 1976 and 2005. We compared prevalence of self-reported hearing loss and tinnitus between all diagnostic childhood cancer groups and siblings, used multivariable logistic regression to analyze the effect of treatment-related factors on hearing loss, and compared the cumulative incidence of hearing loss between different periods of cancer diagnosis.

RESULTS

Prevalence of self-reported hearing loss was higher in survivors (10%) than in siblings (3%, P < 0.001), and highest in survivors of central nervous system tumors (25%). Significant risk factors were treatment with platinum compounds (carboplatin: odds ratio [OR] 2.4; cisplatin: OR 9.4), cranial radiation (>29 Gy: OR >1.7), or brain surgery (OR 2.2). Children diagnosed in 1986-1995, when platinum compounds came into widespread use, had a significantly higher cumulative incidence of hearing loss than those diagnosed in 1976-1985. In the most recent period, 1996-2005, the risk decreased again, both for patients treated with platinum compounds and with cranial radiation.

CONCLUSIONS

Our data show that the burden of hearing loss has stabilized in recently treated survivors, suggesting that survivors have benefited from new treatment regimens that use less ototoxic radiation and more carefully dosed platinum compounds.

Pharmacogenomics in Pediatric Patients: Towards Personalized Medicine

It is well known that drug responses differ among patients with regard to dose requirements, efficacy, and adverse drug reactions (ADRs). The differences in drug responses are partially explained by genetic variation. This paper highlights some examples of areas in which the different responses (dose, efficacy, and ADRs) are studied in children, including cancer (cisplatin), thrombosis (vitamin K antagonists), and asthma (long-acting β2 agonists). For childhood cancer, the replication of data is challenging due to a high heterogeneity in study populations, which is mostly due to all the different treatment protocols. For example, the replication cohorts of the association of variants in TPMT and COMT with cisplatin-induced ototoxicity gave conflicting results, possibly as a result of this heterogeneity. For the vitamin K antagonists, the evidence of the association between variants in VKORC1 and CYP2C9 and the dose is clear. Genetic dosing models have been developed, but the implementation is held back by the impossibility of conducting a randomized controlled trial with such a small and diverse population. For the long-acting β2 agonists, there is enough evidence for the association between variant ADRB2 Arg16 and treatment response to start clinical trials to assess clinical value and cost effectiveness of genotyping. However, further research is still needed to define the different asthma phenotypes to study associations in comparable cohorts. These examples show the challenges which are encountered in pediatric pharmacogenomic studies. They also display the importance of collaborations to obtain good quality evidence for the implementation of genetic testing in clinical practice to optimize and personalize treatment.