Ototoxicity following pediatric hematopoietic stem cell transplantation: a prospective cohort study

Ototoxicity associated with hematopoietic stem cell transplantation; what are the risk factors?

BACKGROUND

Hematopoietic stem cell transplantation (HSCT) is a critical treatment for various hematologic malignancies but can lead to complications, including ototoxicity.

AIM/OBJECTIVES

This study aims to explore the relationship between patient-specific factors and ototoxicity in adult HSCT patients.

MATERIAL AND METHODS

We conducted a retrospective analysis of 129 adult patients who underwent HSCT between 2003 and 2020. Age, gender, transplant indications, conditioning regimens, and pre- and post-transplant audiometry thresholds data were collected from patient files. A hearing loss of 10 decibels or more at two consecutive frequencies or a hearing loss of 20 decibels or more at a single frequency was considered as significant hearing loss (SHL). Statistical analyses were performed to describe factors associated with SHL.

RESULTS

SHL occurred in 16.3% of patients. Older age was significantly associated with an increased risk of SHL (p = .035). Poorer pretransplant hearing thresholds at 4000 Hz and 6000 Hz were also significant predictors of SHL (p = .039 and p = .014, respectively). There was no significant relationship between the donor type of HSCT (autologous vs. allogeneic) and ototoxicity (p = .45), and between conditioning regimens and ototoxicity (p = .860).

CONCLUSIONS

Age and pre-existing hearing levels are significant predictors of ototoxicity post-HSCT. Careful management and monitoring are essential to prevent and address hearing loss in HSCT patients to improve hearing-related quality of life.

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.

Evaluation of Risk Factors Causing Ototoxicity in Childhood Cancers Located in the Head and Neck Region Treated With Platinum-based Chemotherapy

The aim of this study is to evaluate risk factors contributing to the development of ototoxicity in children who received platinum-based chemotherapy for malignancies located in the head and neck region. Eighty-four children who received platinum-based chemotherapy were included. Audiologic evaluations were performed before and after each chemotherapy session through pure tone audiometry, distortion product otoacoustic emissions, and auditory brainstem response tests. Ototoxicity was evaluated using Brock, Muenster, and Chang classifications. Factors such as cranial irradiation, cumulative doses of cisplatin, age, sex, cotreatment with aminoglycosides, schedule of platinum, and type of chemotherapeutic agent were analyzed. Using χ2 tests, all risk factors were matched with the 3 ototoxicity classifications, and multivariate analyses were conducted using statistically significant risk factors. In univariate analyses, being between 5 and 12 years of age, cranial irradiation and being treated with both cisplatin and carboplatin were found to be related to ototoxicity in all 3 classifications. Logistic regression modeling analyses with these 3 risk factors showed that being between 5 and 12 years of age and being treated with both cisplatin and carboplatin significantly increased the risk of ototoxicity.

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.

Hearing and Other Neurologic Problems

Ototoxicity and other neurologic toxicities are potential consequences of exposure to common therapeutic agents used during treatment of childhood cancer, including platinum and vinca alkaloid chemotherapy, cranial radiation, surgery involving structures critical to cochlear and neurologic function, and supportive care medications such as aminoglycoside antibiotics and loop diuretics. This article provides an overview of ototoxicity and other neurologic toxicities related to childhood cancer treatment, discusses the challenges that these toxicities may pose for survivors, and presents an overview of current recommendations for surveillance and clinical management of these potentially life-altering toxicities in survivors of childhood cancers.

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.

Late effects in high-risk neuroblastoma survivors treated with high-dose chemotherapy and stem cell rescue

BACKGROUND

Current treatment strategies have improved the outcome of high-risk neuroblastoma (HRNB) at the cost of increasing acute and late effects of treatment. Although high-dose chemotherapy with stem cell rescue (HDC-SCR) has replaced total body irradiation (TBI) based HRNB therapy, late effects of therapy remain a significant concern.

OBJECTIVES

To describe late effects prevalence, severity, and risks after HDC-SCR.

METHODS

Retrospective chart review of relapse-free HRNB survivors ≥1 year after single HDC-SCR between 2000 and 2015 at Fred Hutchinson Cancer Research Center.

RESULTS

Sixty-one survivors (30 males) were eligible. Median age (years) at SCR was 3.5 years (range 0.7-27 years) and median posttransplant follow-up was 5.4 years (1.2-16.3 years) . Fifty-three (86.9%) survivors developed late effects that increased over time (P < 0.001) and varied in severity from grade 1 (35) to grade 5 (1). These were unrelated to gender or age. High-frequency hearing loss seen in 82% of survivors was the most common abnormality present and 43% of those required hearing aids. Seventeen (27.9%) survivors developed dental late effects and these were most common in children <2 years of age at transplant (P = 0.008). Other toxicities included endocrine (18%), orthopedic (14.8 %), renal (3.9%), melanotic nevi (8.2%), neuropsychological impairments (8.2%), subsequent malignancies (4.9%), pulmonary (4.9%), cardiac (4.9%), and focal nodular liver hyperplasia (3.3%). At 9 years posttransplant, the median height and weight Z-scores were significantly lower than Z-scores at the time of HDC-SCR (-0.01/-1.08, P < 0.001; -0.14/-0.78, P = 0.005).

CONCLUSION

Avoidance of TBI does not mitigate the need to provide diligent, ongoing surveillance for late effects.

Recommendations for ototoxicity surveillance for childhood, adolescent, and young adult cancer survivors: a report from the International Late Effects of Childhood Cancer Guideline Harmonization Group in collaboration with the PanCare Consortium

Childhood, adolescent, and young adult (CAYA) cancer survivors treated with platinum-based drugs, head or brain radiotherapy, or both have an increased risk of ototoxicity (hearing loss, tinnitus, or both). To ensure optimal care and reduce consequent problems-such as speech and language, social-emotional development, and learning difficulties-for these CAYA cancer survivors, clinical practice guidelines for monitoring ototoxicity are essential. The implementation of surveillance across clinical settings is hindered by differences in definitions of hearing loss, recommendations for surveillance modalities, and remediation. To address these deficiencies, the International Guideline Harmonization Group organised an international multidisciplinary panel, including 32 experts from ten countries, to evaluate the quality of evidence for ototoxicity following platinum-based chemotherapy and head or brain radiotherapy, and formulate and harmonise ototoxicity surveillance recommendations for CAYA cancer survivors.

Early and late complications following hematopoietic stem cell transplantation in pediatric patients - A retrospective analysis over 11 years

Hematopoietic stem cell transplantation (HSCT) has been an effective method for treating a wide range of malignant or non-malignant disorders. In case of an autologous HSCT, patients receive their own stem cells after myeloablation before extraction. Allogeneic HSCT uses stem cells derived from a donor. Despite being associated with a high risk of early and long-term complications, it is often the last curative option. 229 pediatric patients, who between 1 January 2005 and 31 December 2015 received an HSCT at the University Children’s Hospital Wuerzburg, were studied. Correlations between two groups were calculated with the Chi square test or with a 2x2-contingency table. To calculate metric variables, the Mann-Whitney-U-test was used. Survival curves were calculated according to Kaplan and Meier. Significance was assumed for results with a p-value <0.05 (CI (Confident Interval) 95%). We retrospectively analyzed 229 pediatric patients (105 females, 124 males) for early and late complications of allogeneic and autologous hematopoietic stem cell transplantation. Median age at HSCT was seven years. Underlying diseases were leukemia (n = 73), lymphoma (n = 22), solid tumor (n = 65), CNS (central nervous system)- tumor (n = 41), and “other diseases” (n = 28). Survival times, overall survival, and event-free survival were calculated. Of all patients, 80.8% experienced complications of some degree, including mild and transient complications. Allo-HSCT (allogeneic HSCT) carried a significantly higher risk of complications than auto-HSCT (autologous HSCT) (n = 118 vs. n = 67; p = < .001) and the remission rate after allo-HSCT was also higher (58.7% vs. 44,7%; p = .032). Especially infection rates and pulmonary complications are different between auto- and allo-HSCT. Leukemia patients had the highest risk of early and late complications (95,0%; p < .001). Complications within HSCT are major risk factors following morbidity and mortality. In order to detect complications and risk factors early, strict recordings are needed to reduce the rate of complication by recognition and prevention of triggering factors. In the future, these factors should receive greater attention in the planning of HSCT post-transplantation care in order to improve the results of the transplantation and establish protocols to prevent their occurrence.

TPMT, COMT and ACYP2 genetic variants in paediatric cancer patients with cisplatin-induced ototoxicity

OBJECTIVES

Cisplatin ototoxicity affects 42-88% of treated children. Catechol-O-methyltransferase (COMT), thiopurine methyltransferase (TPMT) and AYCP2 genetic variants have been associated with ototoxicity, but the findings have been contradictory. The aims of the study were as follows: (a) to investigate these associations in a carefully phenotyped cohort of UK children and (b) to perform a systematic review and meta-analysis.

METHODS

We recruited 149 children from seven UK centres using a retrospective cohort study design. All participants were clinically phenotyped carefully. Genotyping was performed for one ACYP2 (rs1872328), three TPMT (rs12201199, rs1142345 and rs1800460) and two COMT (rs4646316 and rs9332377) variants.

RESULTS

For CTCAE grading, hearing loss was present in 91/120 (75.8%; worst ear) and 79/120 (65.8%; better ear). Using Chang grading, hearing loss was diagnosed in 85/119 (71.4%; worst ear) versus 75/119 (63.0%; better ear). No TPMT or COMT single-nucleotide polymorphisms (SNPs) were associated with ototoxicity. ACYP2 SNP rs1872328 was associated with ototoxicity (P=0.027; worst ear). Meta-analysis of our data with that reported in previous studies showed the pooled odds ratio (OR) to be statistically significant for both the COMT SNP rs4646316 (OR: 1.50; 95% confidence interval: 1.15-1.95) and the ACYP2 SNP rs1872328 (OR: 5.91; 95% confidence interval: 1.51-23.16).

CONCLUSION

We showed an association between the ACYP2 polymorphism and cisplatin-induced ototoxicity, but not with the TPMT and COMT. A meta-analysis was statistically significant for both the COMT rs4646316 and the ACYP2 rs1872328 SNPs. Grading the hearing of children with asymmetric hearing loss requires additional clarification.

Group-Wide, Prospective Study of Ototoxicity Assessment in Children Receiving Cisplatin Chemotherapy (ACCL05C1): A Report From the Children's Oncology Group

Purpose Optimal assessment methods and criteria for reporting hearing outcomes in children who receive treatment with cisplatin are uncertain. The objectives of our study were to compare different ototoxicity classification systems, to evaluate the feasibility of including otoacoustic emissions and extended high frequency audiometry, and to evaluate a central review mechanism for audiologic results for cisplatin-treated children in the cooperative group setting. Patients and Methods Eligible participants were 1 to 30 years, with planned cisplatin-containing treatment. Hearing evaluations were conducted at baseline, before each cisplatin cycle, and at the end of therapy. Audiologic results were assessed and graded by the testing audiologist and by two central review audiologists using the American Speech-Language-Hearing Association Ototoxicity Criteria (ASHA), Common Terminology Criteria for Adverse Events, version 3.0 (CTCAE), and Brock Ototoxicity Grades (Brock). One central reviewer also used the International Society of Pediatric Oncology Ototoxicity Scale (SIOP). Results At the end of treatment, the prevalence of any degree of ototoxicity ranged from 40% to 56%, and severe ototoxicity ranged from 7% to 22%. Compared with CTCAE, SIOP detected significantly more ototoxicity ( P = .004), whereas Brock criteria detected significantly fewer patients with any or severe ototoxicity ( P < .001 for both). SIOP detected ototoxicity earlier than did the other scales. Agreement between the central reviewers and the institutional audiologist was almost perfect for ASHA and Brock, whereas the poorest agreement occurred with CTCAE. Conclusion The SIOP scale may be superior to ASHA, Brock, and CTCAE scales for classifying ototoxicity in pediatric patients who were treated with cisplatin. Future studies should evaluate inter-rater reliability of the SIOP scale.

Effect of Sensorineural Hearing Loss on Neurocognitive Functioning in Pediatric Brain Tumor Survivors

BACKGROUND

Intensified therapy with platinum-based regimens for pediatric brain tumors has dramatically increased the number of pediatric brain tumor survivors (PBTS) but frequently causes permanent sensorineural hearing loss (SNHL). Although neurocognitive decline in PBTS is known to be associated with radiation therapy (RT), SNHL represents a potential additional contributor whose long-term impact has yet to be fully determined.

METHODS

The neurocognitive impact of significant SNHL (Chang scale ≥ 2b) in PBTS was assessed through a retrospective cohort study of audiograms and neurocognitive testing. Scores for neurocognitive domains and subtest task performance were analyzed to identify specific strengths and weakness for PBTS with SNHL.

RESULTS

In a cohort of PBTS (n = 58) treated with platinum therapy, significant SNHL was identified in more than half (55%, n = 32/58), of which the majority required hearing aids (72%, 23/32). RT exposure was approximately evenly divided between those with and without SNHL. PBTS were 6.7 ± 0.6 and 11.3 ± 0.7 years old at diagnosis and neurocognitive testing, respectively. In multivariate analyses adjusted for RT dose, SNHL was independently associated with deficits in intelligence, executive function, and verbal reasoning skills. Subtests revealed PBTS with SNHL to have poor learning efficiency but intact memory and information acquisition.

CONCLUSIONS

SNHL in PBTS increases the risk for severe therapy-related intellectual and neurocognitive deficits. Additional prospective investigation in malignant brain tumors is necessary to validate these findings through integration of audiology and neurocognitive assessments and to identify appropriate strategies for neurocognitive screening and rehabilitation specific to PBTS with and without SNHL.

Ototoxicity and cancer therapy

Ototoxicity is a well-established toxicity associated with a subgroup of antineoplastic therapies that includes platinum chemotherapy, radiation or surgery involving the ear and auditory nerve, and supportive care agents such as aminoglycoside antibiotics and loop diuretics. The reported prevalence of ototoxicity in patients who have received potentially ototoxic therapy ranges from 4% to 90% depending on factors such as age of the patient population, agent(s) used, cumulative dose, and administration techniques. The impact of ototoxicity on subsequent health-related and psychosocial outcomes in these patients can be substantial, and the burden of morbidity related to ototoxic agents is particularly high in very young children. Considerable interindividual variability in the prevalence and severity of ototoxicity has been observed among patients receiving similar treatment, suggesting genetic susceptibility as a risk factor. The development and testing of otoprotective agents is ongoing; however, to the author's knowledge, no US Food and Drug Administration-approved otoprotectants are currently available. Prospective monitoring for ototoxicity allows for comparison of auditory outcomes across clinical trials, as well as for early detection, potential alterations in therapy, and auditory intervention and rehabilitation to ameliorate the adverse consequences of hearing loss. Cancer 2016;122:1647-58. © 2016 American Cancer Society.

Ototoxicity in children with high-risk neuroblastoma: prevalence, risk factors, and concordance of grading scales--a report from the Children's Oncology Group

PURPOSE

Platinum-based therapy is the mainstay for management of high-risk neuroblastoma. Prevalence of platinum-related ototoxicity has ranged from 13% to 95% in previous reports; variability is attributable to small samples and disparate grading scales. There is no consensus regarding optimal ototoxicity grading. Furthermore, prevalence and predictors of hearing loss in a large uniformly treated high-risk neuroblastoma population are unknown. We address these gaps in our study.

PATIENTS AND METHODS

Audiologic testing was completed after administration of cisplatin alone (< 400 mg/m(2); exposure one) or after cisplatin (400 mg/m(2)) plus carboplatin (1,700 mg/m(2); exposure two). Hearing loss was graded using four scales (American Speech-Language-Hearing Association; Brock; Chang; and Common Terminology Criteria for Adverse Events, version 3 [CTCAEv3]).

RESULTS

Of 489 eligible patients, 333 had evaluable audiologic data. Median age at diagnosis was 3.3 years. Prevalence of severe hearing loss differed by scale. For those in the exposure-one group, prevalence ranged from 8% per Brock to 47% per CTCAEv3 (Brock v CTCAEv3 and Chang, P < .01; CTCAEv3 v Chang, P = .16); for those in the exposure-two group, prevalence ranged from 30% per Brock to 71% per CTCAEv3 (all pair-wise comparisons, P < .01). In patients requiring hearing aids, hearing loss was graded as severe in 49% (Brock), 91% (Chang), and 100% (CTCAEv3). Risk factors for severe hearing loss included exposure to cisplatin and carboplatin compared with cisplatin alone and hospitalization for infection.

CONCLUSION

Severe hearing loss is prevalent among children with high-risk neuroblastoma. Exposure to cisplatin combined with myeloablative carboplatin significantly increases risk. The Brock scale underestimates severe hearing loss and should be used with caution in this setting.

Hearing loss among survivors of childhood brain tumors treated with an irradiation-sparing approach

BACKGROUND

Intensive, irradiation-sparing chemotherapy regimens for malignant brain tumors have improved survival and neurocognitive outcomes in very young children. Platinum compounds are pivotal to this approach's success but are associated with hearing loss that markedly reduces quality of life for survivors. The purpose of this study was to determine the prevalence and severity of ototoxicity associated with Head Start and similar irradiation-sparing regimens.

PROCEDURE

A retrospective cohort study was conducted of children treated for malignant brain tumors at Children's Hospital Los Angeles using irradiation-sparing regimens. Patient and treatment characteristics were ascertained. Primary outcomes were post-treatment hearing status, need for hearing aids, and hearing threshold change.

RESULTS

Twenty-nine patients were evaluable. The most common diagnosis was medulloblastoma (n = 14). The median age at diagnosis was 2.0 years (range, 0.2-9.2). Median time from diagnosis to most recent hearing assessment was 1.1 years (mean 2.4; range, 0.2-17.5). Cumulative cisplatin and carboplatin dose was 281 ± 88 mg/m(2) and 1,205 ± 277 mg/m(2) , respectively. All patients had aminoglycoside exposure. Following treatment, 18 patients (62.1%) had abnormal hearing and 11 (37.9%) required hearing aids. At 4,000 Hz, statistically significant hearing loss was documented in the range of 30-40 dB.

CONCLUSIONS

While eliminating cranial irradiation has dramatically improved survival and neurocognitive and neuroendocrine outcomes in this population, clinically significant hearing loss is now the leading late effect due to the necessity of platinum-based chemotherapy. Our results document the need for audiometric monitoring and developing otoprotective strategies in this vulnerable population.

In vitro induction and differentiation of newborn guinea pig hippocampus neural stem cells into cells resembling inner hair cells, using artificial perilymph

OBJECTIVE

To investigate whether artificial perilymph can induce neural stem cells, derived from the hippocampus of newborn guinea pigs, to differentiate into inner ear hair cells, in vitro.

METHODS

Primary neural stem cells derived from the hippocampus of newborn guinea pigs were incubated in medium containing either 10 per cent fetal bovine serum or 5, 10 or 15 per cent artificial perilymph, for three weeks. Differentiated cells were identified using immunofluorescence, Western blot and scanning electron microscopy.

RESULTS

Both fetal bovine serum and artificial perilymph induced the neural stem cells to differentiate into cells with hair-cell-specific antibodies.

CONCLUSION

Neural stem cells can survive in both fetal bovine serum and artificial perilymph, and within these media can differentiate into cells with hair-cell-specific antibodies. This provides an experimental basis for transplantation of neural stem cells into the inner ear.

Auditory late effects of childhood cancer therapy: a report from the Children's Oncology Group

Children treated for malignancies may be at risk for early- or delayed-onset hearing loss that can affect learning, communication, school performance, social interaction, and overall quality of life. Survivors at particular risk include those treated with platinum compounds (cisplatin and/or carboplatin) for neuroblastoma, hepatoblastoma, osteosarcoma, or germ-cell tumors and/or those treated with radiation that affects the ear at doses of >30 Gy for pediatric head and neck tumors. The aims of the Auditory/Hearing Late Effects Task Force of the Children's Oncology Group in this report were to (1) review ototoxicity resulting from childhood cancer therapy including platinum compounds (cisplatin and carboplatin) and radiation, (2) describe briefly cochlear pathophysiology and genetics of cisplatin-related hearing loss, (3) explain the impact of hearing loss resulting from chemotherapy and radiation, and (4) offer recommendations regarding evaluation and management of pediatric patients who are at risk for treatment-related hearing loss. A questionnaire is included as a tool to assist pediatricians in assessment.

Risk-based health monitoring of childhood cancer survivors: a report from the Children's Oncology Group

Because of therapeutic advances over the past 50 years, long-term survival is now a reality for nearly 80% of children and adolescents diagnosed with cancer. The growing population of childhood cancer survivors is notable for its vulnerability to adverse health outcomes, many of which may not become clinically apparent until years after therapy completion. Early detection, prevention, and ameliorative interventions provide the opportunity to reduce cancer-related morbidity and mortality. This review is intended to complement the Children's Oncology Group Long-Term Follow-Up Guidelines for Survivors of Childhood, Adolescent, and Young Adult Cancers. The objective of this review is to familiarize readers with the diverse health risks experienced by childhood cancer survivors that stem from the heterogeneous therapeutic interventions required to achieve disease control.

Volterra Slice otoacoustic emissions recorded using maximum length sequences from patients with sensorineural hearing loss

When normally hearing ears are stimulated with maximum length sequences (MLS) of clicks, a family of non-linear temporal interaction components of otoacoustic emissions (OAEs) can be derived, which have been named Volterra Slice OAEs (VS OAEs). This study investigates the sensitivity of VS OAEs to sensorineural hearing impairment in adults, compared to that of the widely used derived non-linear click evoked OAE (DNL CEOAE). VS OAEs and DNL CEOAEs were obtained from 24 normally hearing and 24 hearing impaired ears using a custom-built MLS system and a Otodynamics 'ILO88' OAE Analyzer, respectively. The results show that, based on waveform reproducibility, VS OAEs are as successful as DNL CEOAEs at separating normal from impaired ears at the audiometric frequencies of 1 and 2 kHz, where a strong correlation is found between the amplitudes of the two OAE types. At 4 kHz however, VS OAEs are a significantly better indicator of hearing loss than DNL CEOAEs. This difference at 4 kHz appears to be due to the lack of stimulus artefact contamination of VS OAEs in the early, high frequency portion of the response. The findings suggest that VS OAEs may provide a better diagnostic and monitoring tool for hearing loss at high frequencies than the conventional DNL CEOAE.

Visual, auditory, sensory, and motor impairments in long-term survivors of hematopoietic stem cell transplantation performed in childhood: results from the Bone Marrow Transplant Survivor study

BACKGROUND

Because of treatment-related toxicity, research is increasingly being focused on long-term sequelae secondary to hematopoietic stem cell transplantation (HSCT) in survivor populations.

METHODS

This study describes the incidence of auditory, sensory, motor, and visual impairments, including cataracts, among 235 individuals who were treated with HSCT during childhood or adolescence. Outcomes were compared with 705 siblings of childhood cancer survivors. Participants completed a survey with questions on posttransplant organ system impairments. Approximately half of survivors were transplanted when younger than 10 years of age. The median length of followup was 11 years.

RESULTS

The cumulative incidence of cataracts was 36% at 15 years post-HSCT, although cataracts occurred only in those who received total body irradiation as an HSCT conditioning agent or head irradiation before transplant. Persistent pain was reported by 21% of survivors. Loss of hearing in one or both ears, and legal blindness in one or both eyes, each occurred after transplant in 2% of survivors. Occurrences were uncommon, but survivors were 4.3 times (95% confidence interval [CI]: 2.0-9.4) more likely to report coordination problems, 7.7 times (95% CI: 3.2-18.5) more likely to report chewing or swallowing problems, and 3.5 times (3.5; 95% CI: 1.6-7.9) more likely to report muscle weakness than those in the comparison group. Muscle weakness was strongly associated with positive history of chronic graft-versus-host disease.

CONCLUSIONS

Increased risks were found for motor impairments, hearing loss, vision loss, and persistent pain among study participants. Cataracts were a frequent adverse effect, suggesting that close monitoring with appropriate intervention for preservation of vision, particularly among those who received total body irradiation, should be a primary goal in survivors of HSCT performed in childhood.

Long-term complications in survivors of advanced stage neuroblastoma

BACKGROUND

Few studies have assessed late effects in neuroblastoma (NB) survivors, particularly those with advanced stage disease.

METHODS

Retrospective analysis of a cohort of advanced stage NB survivors followed in a late effect clinic at a single institution. Screening tests to detect late effects were tailored depending on the individual's treatment exposures.

RESULTS

The study included 63 survivors (31 males). The median age at diagnosis was 3.0 years. The median follow-up from diagnosis was 7.06 years. All patients had surgery and received chemotherapy, 89% received radiation therapy (RT), 62% immunotherapy, and 56% autologous stem cell transplant. Late complications were detected in 95% of survivors and included: hearing loss (62%), primary hypothyroidism (24%), ovarian failure (41% of females), musculoskeletal (19%), and pulmonary (19%) abnormalities. The majority of complications were moderate, with only 4% being life-threatening. Survivors who received cisplatin were at greater risk to develop hearing loss compared to those not so treated (OR 9.74; 95% CI: 0.9-101.6). A total dose of cyclophosphamide greater than 7.4 g was associated with ovarian failure (P = 0.02).

CONCLUSIONS

Late complications occur frequently in survivors of advanced stage NB. The majority of these problems are of mild-moderate severity. Long-term follow-up (LFTU) and screening of this population is essential.