Ototoxicity of preradiation cisplatin for children with central nervous system tumors

The impact of the temporal sequence of cranial radiotherapy and platin-based chemotherapy on hearing impairment in pediatric and adolescent CNS and head-and-neck cancer patients: A report from the PanCareLIFE consortium

The impact of the temporal sequence by which cranial radiotherapy (CRT) and platin-based chemotherapy (PCth) are administered on sensorineural hearing loss (SNHL) in pediatric and adolescent central nervous system (CNS) and head-and-neck (HN) cancer patients has not yet been studied in detail. We examined the ototoxic effects of sequentially applied CRT and PCth. This study included children and adolescents with CNS and HN tumors who participated in the multicountry PanCareLIFE (PCL) consortium. Audiological outcomes were compared between patients who received CRT prior to PCth and those who received it afterwards. The incidence, degree and posttreatment progression of SNHL, defined as Muenster classification grade ≥MS2b, were evaluated in 141 patients. One hundred and nineteen patients were included in a time-to-onset analysis. Eighty-eight patients received CRT prior to PCth (Group 1) and 53 patients received PCth before CRT (Group 2). Over a median follow-up time of 1.6 years, 72.7% of patients in Group 1 experienced SNHL ≥ MS2b compared to 33.9% in Group 2 (P < .01). A time-to-onset analysis was performed for 74 patients from Group 1 and 45 patients from Group 2. Median time to hearing loss (HL) ≥ MS2b was 1.2 years in Group 1 and 4.4 years in Group 2 (P < .01). Thus, audiological outcomes were better for patients who received CRT after PCth than before. This finding should be further evaluated and considered within clinical practice in order to minimize hearing loss in children and adolescents with CNS and HN tumors.

Cisplatin Toxicity in Children with Malignancy

Platinum’ derivates are antineoplastic agents widely adopted for their efficacy for the treatment of many pediatric cancers. The use of cisplatin has positively influenced the results of the cure of different childhood malignancies. However, cisplatin-based treatments are limited by the risk of severe and progressive toxicities, such as oto- or nephrotoxicity, that can be more serious in very young children expecially when high cumulative doses and/or radiotherapy is administered. A correct knowledge of the cisplatin’ pharmacological features might be of interest for clinicians in order to manage its potential toxicities. Based on the positive trend in the cure of children with cancer, it is crucial that all children receiving cisplatin-based chemotherapy have and appropriate and long-term follow-up to improve their quality of life.

Impact of radiation technique, radiation fraction dose, and total cisplatin dose on hearing : Retrospective analysis of 29 medulloblastoma patients

PURPOSE

To analyze the incidence and degree of sensorineural hearing loss (SNHL) resulting from different radiation techniques, fractionation dose, mean cochlear radiation dose (D_mean), and total cisplatin dose.

MATERIAL AND METHODS

In all, 29 children with medulloblastoma (58 ears) with subclinical pretreatment hearing thresholds participated. Radiotherapy (RT) and cisplatin had been applied sequentially according to the HIT MED Guidance. Audiological outcomes up to the latest follow-up (median 2.6 years) were compared.

RESULTS

Bilateral high-frequency SNHL was observed in 26 patients (90%). No significant differences were found in mean hearing threshold between left and right ears at any frequency. A significantly better audiological outcome (p < 0.05) was found after tomotherapy at the 6 kHz bone-conduction threshold (BCT) and left-sided 8 kHz air-conduction threshold (ACT) than after a combined radiotherapy technique (CT). Fraction dose was not found to have any impact on the incidence, degree, and time-to-onset of SNHL. Patients treated with CT had a greater risk of SNHL at high frequencies than tomotherapy patients even though D_mean was similar. Increase in severity of SNHL was seen when the total cisplatin dose reached above 210 mg/m², with the highest abnormal level found 8-12 months after RT regardless of radiation technique or fraction dose.

CONCLUSION

The cochlear radiation dose should be kept as low as possible in patients who receive simultaneous cisplatin-based chemotherapy. The risk of clinically relevant HL was shown when D_mean exceeds 45 Gy independent of radiation technique or radiation regime. Cisplatin ototoxicity was shown to have a dose-dependent effect on bilateral SNHL, which was more pronounced in higher frequencies.

Late Effects of Treatment of Pediatric Central Nervous System Tumors

Central nervous system tumors represent the most common solid malignancy in childhood. Improvement in treatment approaches have led to a significant increase in survival rates, with over 70% of children now surviving beyond 5 years. As more and more children with CNS tumors have longer survival times, it is important to be aware of the long-term morbidities caused not only by the tumor itself but also by tumor treatment. The most common side effects including poor neurocognition, endocrine dysfunction, neurological and vascular late effects, as well as secondary malignancies, are discussed within this article.

Comparison of hearing outcomes after treatment for early-stage external auditory canal cancer

BACKGROUND

The purpose of this study was to compare the hearing outcomes after surgery with reconstruction of the external auditory canal in combination with tympanoplasty, radiotherapy (RT) alone, and surgery followed by postoperative RT for T1 to 2N0M0 external auditory canal cancer.

METHODS

We performed a retrospective, single-institution review of consecutive patients with early-stage external auditory canal cancer treated with surgery and/or RT between April 1997 and August 2013. Audiological data included the pretreatment hearing thresholds and those obtained at 12 months after the completion of therapy.

RESULTS

When we compared the functional gains for air-conduction pure-tone average thresholds and mean air-bone gaps, those in the surgery group (n = 10) were significantly higher than those in the RT (n = 13) and surgery + RT (n = 5) groups.

CONCLUSION

Adequate techniques for reconstruction of the external auditory canal in combination with tympanoplasty after complete surgical resection is useful for hearing preservation in addition to good survival outcomes. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1110-E1116, 2016.

Auditory complications in childhood cancer survivors: a report from the childhood cancer survivor study

BACKGROUND

Studies have found associations between cancer therapies and auditory complications, but data are limited on long-term outcomes and risks associated with multiple exposures.

PROCEDURE

The Childhood Cancer Survivor Study is a retrospective cohort investigating health outcomes of long-term survivors (5+ years) diagnosed and treated between 1970 and 1986 compared to a randomly selected sibling cohort. Questionnaires were completed by 14,358 survivors of childhood cancer and 4,023 sibling controls. Analysis determined the first occurrence of four auditory conditions in two time periods: diagnosis to 5 years post-diagnosis, and ≥ 5 years post-diagnosis. Multivariable analyses determined the relative risks (RR) and 95% confidence interval (CI) of auditory conditions by treatment exposure.

RESULTS

Five or more years from cancer diagnosis, survivors were at increased risk of problems hearing sounds (RR = 2.3; 95% CI: 1.8-2.8), tinnitus (RR = 1.7; 95% CI: 1.4-2.1), hearing loss requiring an aid (RR = 4.4; 95% CI: 2.8-6.9), and hearing loss in 1 or both ears not corrected by a hearing aid (RR = 5.2; 95% CI: 2.8-9.5), when compared to siblings. Temporal lobe and posterior fossa radiation was associated with these outcomes in a dose-dependent fashion. Exposure to platinum compounds was associated with an increased risk of problems hearing sounds (RR = 2.1; 95% CI: 1.3-3.2), tinnitus (RR = 2.8; 95% CI: 1.9-4.2), and hearing loss requiring an aid (RR = 4.1; 95% CI: 2.5-6.7).

CONCLUSIONS

Childhood cancer survivors are at risk of developing auditory complications. Radiation and platinum compounds are determinants of this risk. Follow-up is needed to evaluate the impact of auditory conditions on quality of life.

Carboplatin and ototoxicity: hearing loss rates among survivors of childhood medulloblastoma

PURPOSE

Patients with medulloblastoma are exposed to ototoxic treatments including radiation therapy and platinum chemotherapy. The favorable toxicity profile of carboplatin led us to substitute this chemotherapeutic agent for cisplatin in the HIT-1991, HIT-MED-1999, and HIT-2000 chemotherapy protocols. We retrospectively investigated its consequences in terms of overall survival and ototoxicity rates.

METHODS

Twenty-four medulloblastoma patients were treated according to HIT protocols with carboplatin substitution between April 1999 and June 2006. Nineteen (79%) patients had adequate baseline and post-treatment audiological data. Mean age at diagnosis was 9.3 (range 3.5-18.9) years with a mean follow-up time of 30.8 (8.1-111.3) months. Patients received a mean carboplatin cumulative dose of 2,131 (830-4312) mg/m(2).

RESULTS

Twenty-three patients were alive at the time of assessment. Hearing loss greater than 20 dB was observed in two (10.5%) of 19 patients. Both had grade 2 ototoxicity according to Brock's scale. There were no significant differences between the patients' baseline and post-treatment audiograms at any frequency. The observed hearing loss was significantly correlated to younger age at diagnosis and cumulative carboplatin dose (p<0.05).

CONCLUSIONS

The encouraging overall survival and low hearing loss rates in this medulloblastoma patient cohort suggest that protocols containing carboplatin may offer a viable alternative to standard cisplatin protocols and warrant further investigation.

Cisplatin-Induced Ototoxicity in Osteosarcoma Patients: A Report from the Late Effects Surveillance System

The aim of this study was to analyze cisplatin-induced ototoxicity in a recent study trial. Seventy-four patients who had received cisplatin for the treatment of osteosarcoma (median cumulative dose: 360 mg/m2) were investigated prospectively for ototoxicity in a multicenter trial. Hearing function was tested by audiometry. We evaluated the incidence and dependencies of hearing loss. After cessation of therapy, 51% of the patients showed a hearing loss of >20 dB in the frequency range of 4-8 kHz. Only in one patient a hearing loss was found at 2 kHz, and in none at 1 kHz. At a cumulative cisplatin dose of < or = 240 mg/m2, almost no ototoxicity was found. Incidence and magnitude of hearing loss increased significantly with a higher cumulative dose. Furthermore, hearing thresholds were significantly poorer in children <12 years. A further follow-up investigation showed only a marginal change in hearing function. We conclude that ototoxicity is moderate in our group of patients and probably irreversible.

The prevalence of hearing loss in children and adolescents with cancer

The treatment of cancer in children has several side effects, including ototoxicity. Inner ear structures may be affected and hearing loss may ensue. Aim: To estimate the prevalence of hearing loss in patients with cancer using the American Speech-Language-Hearing Association (ASHA), the Pediatric Oncology Group Toxicity (POGT), and the Bilateral Hearing Loss (PAB) criteria. Study design: a prospective study. Material and Methods: 94 patients admitted between 2003 and 2004 were analyzed. Visual inspection of the external auditory meatus and an audiologic evaluation were done. Descriptive statistics was used to characterize the sample, and Kappa statistics was used to investigate concordance of hearing loss in the three types of classification. Results: The prevalence of hearing loss was 42.5% using ASHA, 40.4% using POGT, and 12.8% using PAB. The concordance of hearing loss was weak for POGT and PAB (k=0.36) and for PAB and ASHA (k=0.33). The concordance between ASHA and POGT was almost perfect (k=0.96). Conclusions: Hearing loss is an important side effect of the treatment of cancer in children. Periodic audiology monitoring is recommended to detect early hearing loss and to revise the treatment if necessary. Adoption of a classification system that detects mild hearing loss (ASHA) is recommended.

A prevalência de perdas auditivas em crianças e adolescentes com câncer

O tratamento do câncer infantil provoca diversos efeitos colaterais, como a ototoxicidade, que é capaz de lesar estruturas da orelha interna e pode levar à perda auditiva. OBJETIVO: Estimar a prevalência de perda auditiva em crianças e adolescentes com câncer, utilizando três classificações: American Speech-Language-Hearing Association (ASHA), Pediatric Oncology Group Toxicity (POGT) e Perda Auditiva Bilateral (PAB). Forma de Estudo: Transversal. MATERIAL E MÉTODO: Analisou-se 94 pacientes atendidos entre 2003 e 2004. Os indivíduos foram submetidos à inspeção visual do meato acústico externo e avaliação audiológica. Para caracterização da amostra utilizou-se a estatística descritiva e para a análise da concordância da perda auditiva nas três classificações foi utilizada a estatística Kappa. RESULTADOS: Houve prevalência de perda auditiva de 42,5% pela ASHA, 40,4% pela POGT e 12,8% pela PAB. A concordância para POGT e PAB, e para PAB e ASHA foi fraca (respectivamente, k=0,36 e k=0,33). A concordância entre ASHA e POGT foi quase perfeita (k=0,96). CONCLUSÕES: A perda de audição é um efeito colateral importante nos pacientes com câncer. A monitorização auditiva é fundamental, pois possibilita detecção precoce e revisão do tratamento. Recomenda-se adotar uma classificação que contemple perdas auditivas leves, como proposta pela ASHA.

The Role for intensity modulated radiation therapy (IMRT) in pediatric population

The purpose of this study was to evaluate our initial experience on the use of IMRT in children with tumors in eloquent or critical locations. Twenty-two children with a median age of 12 years (range 1-17) were treated using IMRT for tumors which were within 2 cm of a critical structure. The treatment locations were spine [2], head and neck [5], abdominopelvic [8], and intracranial [7]. Eighty-two percent (82%) of patients were treated with curative intent despite most patients having advanced or metastatic disease and two patients having previously received standard external beam radiation. IMRT was delivered with a 6MV linear accelerator using dynamic multileaf collimators with a median of six fields. The median follow-up was five months [1-21]. The median administered dose was 45 Gy. The median planning treatment volume (PTV) was 105.4 cc. For the intracranial lesions, the mean doses to the pituitary, brainstem, cochlea, optic nerve, and lens were 31%, 42%, 17%, 27%, and 6% of the total dose, respectively. For the head and neck tumors, the mean doses to the spinal cord and parotid glands were 47% and 49%, respectively. For the pelvic tumors, the mean dose to the bladder, rectum, and small bowel were 51%, 63%, and 22%, respectively. Local failure occurred in one patient. IMRT resulted in substantial sparing of surrounding critical structures and acceptable local control rate for these tumors in children. Further follow-up is needed to assess long-term local control and late effects.

Sensorineural hearing loss after radiotherapy and chemoradiotherapy: a single, blinded, randomized study

PURPOSE

The synergistic ototoxicity of radiation and cisplatin (CDDP) has not been adequately studied. This study investigated whether the use of concurrent and postradiotherapy CDDP in patients with nasopharyngeal carcinoma (NPC) resulted in a difference in postradiotherapy sensorineural hearing when compared with the use of radiotherapy alone.

PATIENTS AND METHODS

Newly diagnosed patients were randomly assigned to the radiotherapy or chemoradiotherapy groups. Bone conduction hearing thresholds were performed before treatment and at 1 week, 6 months, 1 year, and 2 years after completion of radiotherapy. Statistical analysis was performed using the Mann-Whitney U test.

RESULTS

Hearing thresholds averaged over 0.5, 1, and 2 kHz were found to be poorer in the chemoradiotherapy group (58 patients) compared with the radiotherapy group (57 patients) at 1 year (P = .001) and 2 years (P = .03) after radiotherapy. Hearing thresholds at 4 kHz were significantly worse for patients in the chemoradiotherapy arm at all of the postradiotherapy time points studied and were more severely affected than the thresholds at lower speech frequencies. In the radiotherapy group, deterioration of median hearing thresholds, which occurred in the immediate post-treatment period, improved within the first year but deteriorated again at 2 years. In the chemoradiotherapy group, median hearing threshold deterioration, which started immediately after radiotherapy, stabilized by 1 year.

CONCLUSION

Patients with NPC who received radiotherapy and concurrent/adjuvant chemotherapy using CDDP experienced greater sensorineural hearing loss compared with patients treated with radiotherapy alone, especially to high-frequency sounds in the speech range. Normal inner ear tissue tolerance, which was once defined only for radiotherapy patients alone, should be redefined in chemoradiotherapy patients.

Ototoxicity from high-dose use of platinum compounds in patients with neuroblastoma

BACKGROUND

The young age of neuroblastoma patients makes them especially prone to the ototoxic effects of widely used treatments that feature aggressive use of platinum compounds. We present data defining the extent of the problem in a large series of neuroblastoma patients whose induction included high-dose cisplatin/etoposide (HD-P/E) as used in both the Memorial Sloan-Kettering Cancer Center N7 regimen and the Children's Oncology Group A3973 study.

METHODS

N7/A3973 patients were divided into 3 groups: Group 1 had hearing tested after induction, that included 2 cycles of HD-P/E (cumulative cisplatin = 400 mg/m(2)); Group 2 had hearing tested after induction, that included 3 cycles of HD-P/E (cumulative cisplatin = 600 mg/m(2)); and Group 3 had hearing tested following carboplatin-containing myeloablative therapy administered after induction, that included 2 cycles of HD-P/E. Ototoxicity was scored by the Brock method.

RESULTS

All 3 groups had similar clinical characteristics, including median age at diagnosis of about 3 years. Little or no hearing loss in the speech range (Grade 0/1) was documented in 21 (32%) of the 65 Group 1 patients, 5 (10%) of the 50 Group 2 patients, and 9 (15.5%) of the 58 Group 3 patients. Severe (Grade 3/4) deficits affected 25% of Group 1, 54% of Group 2, and 50% of Group 3 patients. Patients < 5 years at diagnosis had greater ototoxicity than older patients had, with adolescents/adults being the least affected. Findings were stable in repeated assessments over 2 or more years.

CONCLUSIONS

Ototoxicity is a serious and pervasive problem in this patient population. Strategies to ameliorate ototoxicity without compromising on antitumor activity of treatments are urgently needed.

Ototoxicity in Children Receiving Platinum Chemotherapy: Underestimating a Commonly Occurring Toxicity That May Influence Academic and Social Development

Purpose

To describe the frequency and severity of ototoxicity in a series of pediatric patients treated with platinum-based chemotherapy.

Patients and Methods

Serial audiologic evaluations were conducted for 67 patients aged 8 months to 23 years who received platinum-based chemotherapy. Audiologic data was analyzed to determine time to hearing-loss using American Speech-Language-Hearing Association (ASHA) criteria, and the effects of treatment and patient characteristics on the incidence and severity of ototoxicity.

Results

Bilateral decreases in hearing were seen in 61% of patients (median time to hearing loss, 135 days). Children treated for medulloblastoma, osteosarcoma, and neuroblastoma had greater incidence and severity of hearing loss. Agreement between the usually reported National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) and ASHA criteria was inadequate.

Conclusion

Traditional reporting of toxicity data (CTCAE) has under-reported ototoxicity and minimized the significance of hearing loss in children. As pediatric patients experience improved survival, the effects and implications of high-frequency hearing loss with regard to academic achievement and speech and language development are important considerations, especially in patients younger than 5 years.

Ototoxicity of cisplatin plus standard radiation therapy vs. accelerated radiation therapy in glioblastoma patients

PURPOSE

To assess the effect of cisplatin (CDDP) plus concurrent radiation therapy on hearing loss.

METHODS

451 patients with glioblastoma multiforme (GBM) were randomly assigned after surgery to: Arm A: Carmustine (BCNU) + standard radiation therapy (SRT); Arm B: BCNU + accelerated radiation therapy (ART: 160 cGy twice daily for 15 days); Arm C: CDDP + BCNU + SRT; or Arm D: CDDP + BCNU + ART. Patients on arms C and D received audiograms at baseline, and prior to the start of RT, and prior to cycles 3 and 6. Otologic toxicities were recorded at each visit.

RESULTS

56% of patients had hearing loss at baseline. 13% and 50% of patients experienced worsening ototoxicity after 1 year of treatment in arms A and B vs. C and D, respectively, with 13% of those on arms C and D experiencing significant ototoxicity (>or= grade 3) at 6 months. Increasing age was associated with an increased risk of ototoxicity.

CONCLUSIONS

Increased exposure to CDDP increases the risk of ototoxicity over time. Older patients are more susceptible to hearing loss with CDDP. The low proportion of patients with clinically significant ototoxicity suggests that baseline screening is unnecessary in GBM patients.

Sensory neural hearing loss after concurrent cisplatin and radiation therapy for nasopharyngeal carcinoma

Sensory neural hearing loss (SNHL) was evaluated in the patients who were treated with concurrent chemoradiation therapy for nasopharyngeal carcinoma. Ten from 48 ears showed persistent SNHL. Radiotherapy techniques, radiation dose to inner ear and post-treatment otitis media were significant predicting factors for SNHL.

Early neuro-otologic effects of three-dimensional irradiation in children with primary brain tumors

PURPOSE

Central nervous system (CNS) irradiation can cause sensorineural hearing loss. The relationship between the dose to the cochlea and the development of hearing loss is unknown. Conformal radiation therapy (CRT) techniques facilitate accurate cochlear dosimetry. We modeled hearing threshold levels (HTL) after CRT in children with localized primary brain tumors (ependymoma, low- or high-grade astrocytoma, craniopharyngioma, or CNS germinoma) by using cochlear dose and clinical variables.

PATIENTS AND METHODS

We evaluated 72 children (median age, 9.5 years) with audiograms before and every 6 months after CRT (median follow-up, 16.6 months; range, 4.3-42.6 months). We used a mixed-effects model to predict change in hearing for each ear as a function of time, cochlear dose, and clinical variables.

RESULTS

Hearing was affected the greatest in patients with CSF shunts and pre-CRT ototoxic chemotherapy, enhanced by cochlear dose, and was more prominent on the right side. Hearing impairment after CRT alone occurred at low and intermediate frequencies in patients with shunts and supratentorial tumors when the cochlear dose exceeded 32 Gy. Patients with shunts and central supratentorial tumors developed intermediate-frequency hearing loss after CRT alone regardless of dose.

CONCLUSIONS

Hearing loss during the first 4 years after CRT alone is uncommon, although patients with shunts and supratentorial tumors appear to be at increased risk for low- and intermediate-frequency effects. CSF shunting and increased cochlear dose enhance the effect of ototoxic chemotherapy. If possible, the average cochlear dose should be <32 Gy over a 6-week course of treatment until more specific dose data become available.

Intensity-modulated radiation therapy for pediatric medulloblastoma: early report on the reduction of ototoxicity

PURPOSE

The combination of cisplatin chemotherapy and radiation therapy for the treatment of medulloblastoma has been shown to cause significant ototoxicity, impairing a child's cognitive function and quality of life. Our purpose is to determine whether the new conformal technique of intensity-modulated radiation therapy (IMRT) can achieve lower rates of hearing loss by decreasing the radiation dose delivered to the cochlea and eighth cranial nerve (auditory apparatus).

PATIENTS AND METHODS

Twenty-six pediatric patients treated for medulloblastoma were retrospectively divided into two groups that received either conventional radiotherapy (Conventional-RT Group) or IMRT (IMRT Group). One hundred thirteen pure-tone audiograms were evaluated retrospectively, and hearing function was graded on a scale of 0 to 4 according to the Pediatric Oncology Group's toxicity criteria. Statistical analysis comparing the rates of ototoxicity was performed using Fisher's exact test with two-tailed analysis.

RESULTS

When compared to conventional radiotherapy, IMRT delivered 68% of the radiation dose to the auditory apparatus (mean dose: 36.7 vs. 54.2 Gy). Audiometric evaluation showed that mean decibel hearing thresholds of the IMRT Group were lower at every frequency compared to those of the Conventional-RT Group, despite having higher cumulative doses of cisplatin. The overall incidence of ototoxicity was lower in the IMRT Group. Thirteen percent of the IMRT Group had Grade 3 or 4 hearing loss, compared to 64% of the Conventional-RT Group (p < 0.014).

CONCLUSION

The conformal technique of IMRT delivered much lower doses of radiation to the auditory apparatus, while still delivering full doses to the desired target volume. Our findings suggest that, despite higher doses of cisplatin, and despite radiotherapy before cisplatin therapy, treatment with IMRT can achieve a lower rate of hearing loss.

Ototoxic impact of cisplatin in pediatric oncology patients

OBJECTIVE

To describe hearing changes in a group of 28 children (age range, 8-180 mo) undergoing protocol-based cisplatin therapy.

METHODS

Conventional, play audiometry, visual reinforcement audiometry (VRA), immittance audiometry, transient click evoked otoacoustic emissions (OAEs), and auditory brainstem response (ABR) evoked potentials were used to assess peripheral sensitivity and for threshold determination.

RESULTS

Bilateral symmetrical high-frequency sensorineural hearing loss was noted in 9 of the 28 children (26%). Hearing loss was evident as early as 1 month after chemotherapy and as late as 50 months and was not dependent on individual or cumulative dosage of cisplatin.

CONCLUSIONS

1) Presence of sensorineural hearing loss was independent of individual and/or cumulative dosage of cisplatin; 2) audiologic assessment should be incorporated into a child's periodic medical evaluations after chemotherapy treatment, as onset of sensorineural hearing loss cannot be predicted; 3) personal hearing aids may be indicated for those children with hearing loss affecting the low- to mid-frequencies; a personal assistive listening device (frequency modulated system) may be more appropriate for losses above 3000 Hz; and 4) evaluation and intervention by a speech-language pathologist may be indicated to address possible articulation or language development problems consequent to hearing loss.

Long-term sensorineural hearing deficit following radiotherapy in patients suffering from nasopharyngeal carcinoma: A prospective study

BACKGROUND

This was a prospective study to evaluate the effect of radical external irradiation on inner ear function after treatment of nasopharyngeal carcinoma.

METHODS

Pure tone audiograms were performed at regular intervals before, after, and up to 4.5 years following completion of radiotherapy.

RESULTS

Two hundred ninety-four patients (526 ears) were included. Within 3 months after radiotherapy, deterioration of bone conduction threshold at 4 kHz and pure tone average (average of 0.5 kHz, 1 kHz, and 2 kHz) were noted in 164 ears (31%) and 75 ears (14%), respectively. Patients older than 50 years and ears with threshold below 60 dB at 4 kHz before radiotherapy were significant factors (p < 0.01 and p < 0. 001) associated with a 4 kHz loss. In 40% of these ears, recovery was evident at 2 years. With follow-up for 4.5 years, the probability of significant threshold deterioration increased with time.

CONCLUSION

Sensorineural hearing loss started soon after radiotherapy. Early changes could be reversible while the probability of persistent hearing loss continued to increase.

Cisplatin ototoxicity in developing gerbils

This experimental study was undertaken to investigate the dose-related effect of cisplatin exposure in young gerbils (2 weeks of age) and explore the relationship between different methods used to monitor auditory function after exposure to cisplatin. Four groups of animals, including a control group, were used. The treatment groups, D1 (n = 6), D2 (n = 7) and D3 (n = 6), received one, two, and three doses of cisplatin (5 mg/kg/dose), respectively, at weekly intervals. Treated animals were first exposed to cisplatin at 2 weeks of age. Distortion product otoacoustic emissions (DPOAE) and auditory brainstem responses (ABR) were measured in treated and control animals at 6 weeks of age. The effects of dose and frequency on the DPOAE amplitude, as well as the relationship between the DPOAE and the ABR thresholds were analyzed. Animals in the D1 and D3 groups demonstrated significant elevation of DPOAE and ABR thresholds. Interestingly, animals in the D2 group demonstrated a bimodal distribution of DPOAE and ABR responses, with four animals severely affected and three not showing an effect. A tendency for a bimodal distribution of DPOAE and ABR responses was also observed in the D1 group, at frequencies below 8 kHz.

Cisplatin ototoxicity: the importance of baseline audiometry

The role and optimal use of audiometry in monitoring for cisplatin ototoxicity are incompletely defined. Audiograms were obtained from 217 patients before treatment with cisplatin-based chemotherapy for cancers of the esophagus, lung, or head and neck. Posttreatment audiometry then was conducted in 53 of these patients. Chemotherapy consisted of two (87%) or three (13%) courses of cisplatin at a dose of 20 mg/m2/day given as a continuous intravenous infusion over 4 days. Simultaneous 5-fluorouracil or paclitaxel also was given, and 38% received concurrent radiation therapy to the head and neck. Air-conduction thresholds for each ear were obtained at 250, 500, 1000, 2000, 4000, 6000, and 8000 Hz. Three three-frequency pure-tone averages (PTA) also were calculated. Framingham gender-specific, age-adjusted norms were used, beginning at age 60 to correct for presbycusis, and the upper limit of normal was calculated as the greater of the Framingham mean plus twice the standard error, or 25 dB. Hearing abnormality was defined as a threshold >10 dB above the norm for any PTA, or >20 dB above the norm for any individual frequency. Hearing loss was defined as an elevation over baseline threshold of >10 dB for any PTA or >20 dB for any individual frequency. Of the 217 patients who underwent baseline testing, 57 (26%) were found to have hearing abnormality in excess of the expected presbycusis. Post-cisplatin audiograms demonstrated hearing loss in 19 of the 53 retested patients (36%) when compared with their own baseline. As determined by tympanometry, none of these subjects had a conductive component to their hearing loss. These observations were independent of the duration of follow-up after treatment and of the total dose of cisplatin administered. The authors conclude that significant preexisting hearing abnormality is common in this patient population and that, even after low-dose cisplatin administration, additional hearing loss occurs frequently. Baseline testing is mandatory if follow-up studies are to be adequately interpreted.

[Combined chemoradiotherapy of tumors in the child]

The high chemosensitivity of pediatric tumors along with their natural propensity for an early distant dissemination have stimulated the interest for chemo-radiation combinations in children since the mid 50s. Following the early experiments in nephroblastomas on the interaction of Actinomycin-D and radiotherapy, multiple national and international studies have been conducted since the mid 70s with considerable success: nowadays most pediatric tumors enjoy a long term survival in excess of 70%. Like their adult counterparts, these associations aim to induce an early control of the primary tumor and distant spreading (spatial cooperation) but also, more specifically in children, to limit the toxicity on normal tissues when treatment intensity can be further reduced. The association of an initial chemotherapy followed by local radiation at a dose and in a volume adapted to the response to chemotherapy along with associated prognostic factors has become widely tested in national and international studies conducted in Hodgkin's disease, Ewing's sarcoma, medulloblastomas, and brain tumors in the very young. Conversely, concomitant associations have remained limited to high-risk subgroups (parameningeal rhabdomyosarcomas for example) due to their potential hazards.

Sensorineural hearing loss in patients treated for nasopharyngeal carcinoma: a prospective study of the effect of radiation and cisplatin treatment

PURPOSE

The pattern of sensorineural hearing loss (SNHL) after primary treatment for nasopharyngeal carcinoma (NPC) was studied, and the effect of cisplatin, radiotherapy does, and fractionation were evaluated.

METHODS AND MATERIALS

One hundred thirty-two patients, 227 ears, and 1100 audiogram reports were analyzed. Radiotherapy dose ranged from 59.5 to 76.5 Gy. Fifty-two patients received preirradiation cisplatin, total dose 100-185 mg/m(2). Serial postirradiation bone conduction thresholds at 0.5 kHz, 1 kHz, 2 kHz, and 4 kHz were compared with pretreatment thresholds at respective frequencies. Increase of at least 15 dB was considered as significant and was further grouped as transient or persistent SNHL. Univariate and multivariate analyses were performed to identify predicting factors for persistent SNHL.

RESULTS

At median follow-up of 30 months, 24.2% of ears developed persistent SNHL. High frequency was more affected than low frequencies, 22 vs. 5.3%. Males were more affected than females, 29.4 vs. 15.5%, p = 0.0132. Incidence of persistent SNHL increased with age, with 0, 17.2, and 37.4% of patients aged under 30, between 30-50 and over 50 affected, respectively, p = 0.0001. High incidence was found in patient with postirradiation serous otitis media (SOM), 46.9%. Chemotherapy with cisplatin and radiation dose or fractionation had no significant effect. Multivariate analysis confirmed age, sex, and postirradiation SOM as significant prognostic factors for persistent SNHL.

CONCLUSIONS

Transient and persistent SNHL occurred after radiotherapy, more commonly affecting high frequency. A low dose of preirradiation cisplatin did not increase the risk. A dose fractionation effect of radiotherapy was not confirmed in this study.

Ototoxicity in children with malignant brain tumors treated with the "8 in 1" chemotherapy protocol

BACKGROUND

Adjuvant chemotherapy has improved the outcome of childhood malignant brain tumors in large randomized trials. With increasing survival rates, treatment toxicity has become a matter of concern. Radiation therapy and cisplatinum are known to be ototoxic.

METHODS

We evaluated the incidence and factors predisposing to ototoxicity in children treated with the "8 in 1" chemotherapy protocol in Finland during 1986--1993. Thirty-five of the 82 children survived for at least 1 year after diagnosis. Thirty of these children were old enough to have an audiogram.

RESULTS

Seventeen of the 30 children had normal hearing, seven had hearing loss at high frequencies, and six (20%) had severe hearing loss in the speech range. The risk factors for severe hearing loss were young age, a high cumulative dose of cisplatinum, and deteriorating renal function. In the presence of these factors, the risk of severe hearing loss was over 50%. Hearing loss at high frequencies could occur after low cumulative doses of cisplatinum, but severe hearing loss correlated with high cumulative doses.

CONCLUSIONS

Cisplatinum-induced hearing loss at high frequencies is common, but hearing loss in the speech range also occurs, particularly in children with predisposing factors, and may progress insidiously and rapidly. Therefore a hearing test before each "8 in 1" course is important.

Evaluation of response to postradiation eight in one chemotherapy in childhood brain tumors

Ten children, 3 to 15 years of age with high risk primary brain tumors were treated with postradiation 'eight in one' chemotherapy; vincristine, lomustine, procarbazine, hydroxyurea, cisplatin, cytosine arabinoside, cyclophosphamide and methylprednisolone. The tumors comprised of three medulloblastomas, two primitive neuroectodermal tumors, one ependymoblastoma and four anaplastic ependymomas. Treatment involved surgery (two total resection, six subtotal and two biopsy only) followed by conventional radiotherapy (primary tumor: 50-54 Gy, whole brain: 30-45 Gy, and spinal axis: 25-36 Gy). Objective tumor response with radiotherapy was achieved in 7 of 9 patients (78%) (6/8 patients with residual tumor and one patient with complete resection but positive cerebrospinal fluid cytology). Complete response was attained in 4 of 9 patients (44%). 'Eight in one' chemotherapy was initiated four weeks after radiation and repeated at 4 weekly intervals for 5-8 courses. Postradiation 'eight in one' failed to show any additional effect on tumor responses. Median survival was 34 months (range 9-48 months) with five of ten patients alive: four in complete and one in partial remission. All the five survivors were among the patients who had achieved response to initial treatment. This result suggested that degree of response to initial treatment might determine subsequent outcome and thus the choice of modality for initial therapy might be important.

A case of massive cisplatin overdose managed by plasmapheresis

OBJECTIVES

Accidental cisplatin overdose occurs with increasing frequency despite the safeguards taken in prescription and administration, since cisplatin has been used increasingly for the treatment of numerous malignancies. Accidentally, a 59-year-old male received massive cisplatin overdose of 300mg/m2.

METHODS

Laboratory documentation included measurement of cisplatin concentrations by flameless atomic absorption spectroscopy (Varian, Spectra AA 300).

RESULTS

Toxicities included severe emesis, myelosuppression, renal failure, mental deterioration with hallucination, dim vision and hepatic toxicity. Plasmapheresis was effective in lowering the platinum concentration from greatest 2979 ng/ml to 185 ng/ml and appeared to be of clinical benefit. Granulocyte-macrophage colony stimulating factor (GM-CSF) was used to ameliorate myelosuppression. The patient's renal function was restored 3 months later and partial response of esophageal cancer was obtained.

CONCLUSIONS

Plasmapheresis was effective in lowering the platinum concentration in massive cisplatin overdose. This case heightens awareness to the possibility of accidental cisplatin overdose and the benefits of prompt management.

Response to neoadjuvant chemotherapy in children with pineoblastoma

BACKGROUND

The outlook of children with pineoblastoma treated with radiation therapy alone is extremely poor, but neoadjuvant chemotherapy has been tried only in a few cases of this rare childhood brain tumor with poor prognosis.

METHODS

Three consecutive children 3 to 7 years of age received neoadjuvant chemotherapy consisting of etoposide 100 mg/m2 days 1 to 3, cisplatin 100 mg/m2 day 1, and vincristine 1.5 mg/m2 day 1, repeated every 4 weeks. After four courses of chemotherapy, patients underwent craniospinal irradiation. The radiation doses to the primary site ranged from 5040 to 5440 cGy and craniospinal axis radiation dose was 2520 to 3060 cGy.

RESULTS

After chemotherapy, mild myelosuppression occurred in all three and mild to moderate bilateral high-frequency sensorineural hearing loss occurred in two of the three patients. One patient remains in near complete resolution of the tumor at 2 years after diagnosis and another remains in CR for 5 years. One patient achieved PR for 5 months but eventually died of progressive tumor.

CONCLUSIONS

This study suggests that the neoadjuvant chemotherapy as used here is effective and has acceptable toxicity.

Fatal brain stem necrosis after standard posterior fossa radiation and aggressive chemotherapy for metastatic medulloblastoma

A 3-year-old girl received conventional-dose external beam posterior fossa irradiation (5400 cGy in 30 fractions over 40 days) for good-risk medulloblastoma. Soon thereafter, she experienced an extraneural (occipital scar, cervical lymph nodes) and central nervous system (CNS) recurrence. Intensive cisplatin and cyclophosphamide chemotherapy led to rapid disappearance of the extraneural disease. Methotrexate was administered via a ventricular reservoir. After 2 months of chemotherapy, CNS toxicity progressed rapidly from ataxia to paraplegia to quadriplegia to central respiratory failure. Radiographic scans and autopsy material revealed brain stem necrosis. This unusual toxicity raises concern about the safety of aggressive systemic chemotherapy and intrathecal therapy, when given after conventional radiotherapy.

Hyperfractionated radiotherapy and polychemotherapy in brain stem tumors in children

Between October 1989 and January 1991 five children with brain stem tumors were treated with sequential chemo- and radiotherapy. The polychemotherapy consisted of procarbazine, ifosfamide, etoposide, methotrexate, cisplatin and cytosine arabinoside. Locally, hyperfractionated radiotherapy was delivered at a total dose of 63.8 Gy (1.1 Gy twice daily, 10 fractions per week). After a median observation time of 11.8 (range 4-23) months from diagnosis three children are alive and without evidence of tumor progression. Two patients died from tumor progression 11 and 16 months respectively after initiation of therapy.

Sensori-neural hearing loss in patients treated with irradiation for nasopharyngeal carcinoma

The present investigation has been carried out to evaluate the sensitivity of the inner ear to irradiation. Cochlear function was tested in a cohort of 22 patients before and 7-84 months after receiving external irradiation for nasopharyngeal carcinoma. The pre-irradiation sensori-neural hearing threshold at 500, 1000, 2000, and 4000 Hz was used as a baseline for the individual patient, and the observed sensori-neural hearing loss (SNHL) was calculated as the difference between pre- and post-irradiation values. The pre-irradiation hearing level or patient age was not correlated with the actual SNHL. In contrast, there was a significant correlation between the total radiation dose to the inner ear and the observed hearing impairment. SNHL was most pronounced in the high frequencies, with values up to 35 dB (4000 Hz) and 25 dB (2000 Hz) in some patients. The latent period for the complication appeared to be 12 months or more. The deleterious effect of irradiation on the hearing should be kept in mind both in treatment planning and in the follow-up after radiotherapy.