Barriers to long-term follow-up in pediatric Hodgkin lymphoma survivors

BACKGROUND/PURPOSE

Pediatric Hodgkin lymphoma (HL) survivors have an increased risk of late effects following treatment. Barriers at the patient, provider, and payor level adversely affect adherence to long-term follow-up.

METHODS

We conducted a retrospective chart review of HL survivors diagnosed from 1999 to 2014 at Texas Children's Hospital. HL survivors were considered lost to follow-up if there were no documented visits to Texas Children's Cancer Center Long-Term Survivor (LTS) clinic for 2 or more years after their last LTS clinic visit. Univariate and multivariable logistic regression analyses were conducted to explore factors contributing to loss to follow-up. Reasons for not attending subsequent LTS visits were assessed by phone interviews in a subset of lost to follow-up patients.

RESULTS

There were 120 HL survivors who had at least one LTS clinic visit in this timeframe; 64 (53%) were classified as lost to follow-up, and of these, 23 (36%) were interviewed. Eleven (47%) indicated that the reason for failure to follow-up was lack of or inadequate insurance, and seven (30%) stated they were unaware of the importance of continued follow-up. Loss to follow-up was associated with lack of insurance, earlier diagnosis, and lack of comorbidities in univariate analyses. Only earlier year of diagnosis (odds ratio [OR] 0.84, 95% confidence interval [CI]: 0.7-0.9, p = .01) and lack of insurance (OR 22.2, 95% CI: 4-123, p < .001) were associated with loss to follow-up in multivariable analyses.

CONCLUSIONS

Insurance status and awareness of the need for long-term follow-up care are key factors associated with loss to follow-up in survivors of HL. Targeted education and low-cost options for survivorship care are potential strategies for improving adherence to long-term follow-up care in HL survivors.

Temporal changes in treatment and late mortality and morbidity in adult survivors of childhood glioma: a report from the Childhood Cancer Survivor Study

Pediatric glioma therapy has evolved to delay or eliminate radiation for low-grade tumors. This study examined these temporal changes in therapy with long-term outcomes in adult survivors of childhood glioma. Among 2,501 5-year survivors of glioma in the Childhood Cancer Survivor Study diagnosed 1970-1999, exposure to radiation decreased over time. Survivors from more recent eras were at lower risk of late mortality (≥5 years from diagnosis), severe/disabling/life-threatening chronic health conditions (CHCs) and subsequent neoplasms (SNs). Adjusting for treatment exposure (surgery only, chemotherapy, or any cranial radiation) attenuated this risk (for example, CHCs (1990s versus 1970s), relative risk (95% confidence interval), 0.63 (0.49-0.80) without adjustment versus 0.93 (0.72-1.20) with adjustment). Compared to surgery alone, radiation was associated with greater than four times the risk of late mortality, CHCs and SNs. Evolving therapy, particularly avoidance of cranial radiation, has improved late outcomes for childhood glioma survivors without increased risk for late recurrence.

Adaptive, behavioral, and emotional outcomes following postoperative pediatric cerebellar mutism syndrome in survivors treated for medulloblastoma

OBJECTIVE

Patients who experience postoperative pediatric cerebellar mutism syndrome (CMS) during treatment for medulloblastoma have long-term deficits in neurocognitive functioning; however, the consequences on functional or adaptive outcomes are unknown. The purpose of the present study was to compare adaptive, behavioral, and emotional functioning between survivors with and those without a history of CMS.

METHODS

The authors examined outcomes in 45 survivors (15 with CMS and 30 without CMS). Comprehensive neuropsychological evaluations, which included parent-report measures of adaptive, behavioral, and emotional functioning, were completed at a median of 2.90 years following craniospinal irradiation.

RESULTS

Adaptive functioning was significantly worse in the CMS group for practical and general adaptive skills compared with the group without CMS. Rates of impairment in practical, conceptual, and general adaptive skills in the CMS group exceeded expected rates in the general population. Despite having lower overall intellectual functioning, working memory, and processing speed, IQ and related cognitive processes were uncorrelated with adaptive outcomes in the CMS group. No significant group differences or increased rates of impairment were observed for behavioral and emotional outcomes.

CONCLUSIONS

Survivors with CMS, compared with those without CMS, are rated as having significant deficits in overall or general adaptive functioning, with specific weakness in practical skills several years posttreatment. Findings from this study demonstrate the high risk for ongoing functional deficits despite acute recovery from symptoms of CMS, highlighting the need for intervention to mitigate such risk.

Improving Time to Antibiotic Administration for Pediatric Oncology Patients With New-Onset Fever

PURPOSE

Time to antibiotic administration (TTA) in <60 minutes for children with neutropenic fever presenting to an emergency room is associated with reduced incidence of sepsis and intensive care admission. As such, TTA is used as a national quality metric for pediatric oncology patients. At our center, in 2020, 19% of the hospitalized patients with a new fever encounter were receiving antibiotics in <60 minutes, prompting a multidisciplinary approach to reach a goal of >90% in all pediatric patients with cancer with a new fever.

METHODS

A multidisciplinary team completed four Plan-Do-Study-Act cycles between March 2021 and September 2023. We implemented education initiatives, an updated handoff smartphrase guiding the on-call team, an antibiotic champion (AC) nursing role, a revised fever plan for handoff, a rapid-response team to address new fevers, and an algorithm for blood culture collection. Data were collected, analyzed, and reported biweekly with feedback sought for delays in TTA.

RESULTS

There was a total of 639 new fevers in 329 unique oncology patients. As of September 4, 2023, average TTA decreased from 89 minutes at baseline to 46.4 minutes for more than 12 months. The percentage of patients receiving first dose of antibiotic in <60 minutes also increased from 19% to 93.7%, which was sustained as well. The most effective interventions were creation of the AC role and streamlining the blood culture collection process.

CONCLUSION

This project demonstrates the importance of multidisciplinary involvement for providing optimal care. Specific implementation of targeted education, an AC role, and development of an algorithm streamlining the processes led to meaningful targeted improvements. Further analyses will explore the impact of these interventions on patient outcomes.

Neurologic morbidity and functional independence in adult survivors of childhood cancer

OBJECTIVE

To examine associations between neurologic late effects and attainment of independence in adult survivors of childhood cancer treated with central nervous system (CNS)-directed therapies.

METHODS

A total of 7881 survivors treated with cranial radiation therapy (n = 4051; CRT) and/or intrathecal methotrexate (n = 4193; IT MTX) ([CNS-treated]; median age [range] = 25.5 years [18-48]; time since diagnosis = 17.7 years [6.8-30.2]) and 8039 without CNS-directed therapy reported neurologic conditions including stroke, seizure, neurosensory deficits, focal neurologic dysfunction, and migraines/severe headaches. Functional independence was assessed using latent class analysis with multiple indicators (independent living, assistance with routine and personal care needs, ability to work/attend school, attainment of driver's license, marital/partner status). Multivariable regression models, adjusted for age, sex, race/ethnicity, and chronic health conditions, estimated odds ratios (OR) or relative risks (RR) for associations between neurologic morbidity, functional independence, and emotional distress.

RESULTS

Among CNS-treated survivors, three classes of independence were identified: (1) moderately independent, never married, and non-independent living (78.7%); (2) moderately independent, unable to drive (15.6%); and (3) non-independent (5.7%). In contrast to 50% of non-CNS-treated survivors and 60% of siblings, a fourth fully independent class of CNS-treated survivors was not identified. History of stroke (OR = 2.50, 95% CI: 1.70-3.68), seizure (OR = 9.70, 95% CI: 7.37-12.8), neurosensory deficits (OR = 2.67, 95% CI: 2.16-3.31), and focal neurologic dysfunction (OR = 3.05, 95% CI: 2.40-3.88) were associated with non-independence among CNS-treated survivors. Non-independence was associated with emotional distress symptoms.

INTERPRETATION

CNS-treated survivors do not attain full independence comparable to non-CNS-treated survivors or siblings. Interventions to promote independence may be beneficial for survivors with treatment-related neurological sequalae.

Leuprolide Protects Ovarian Reserve in Adolescents Undergoing Gonadotoxic Therapy

Purpose: Treatment sequelae compromising reproductive health are highly prevalent in childhood cancer survivors, and a main determinant of health and quality of life. Follicular reserve determines ovarian function life span; thus, its preservation is important in the care of female survivors. Anti-Müllerian hormone (AMH) is a biomarker to measure functional ovarian reserve. We aimed to evaluate the effect of leuprolide during gonadotoxic therapy on pubertal females' post-treatment functional ovarian reserve using AMH levels. Methods: We conducted a single-center retrospective study including all pubertal females who had undergone gonadotoxic treatments between January 2010 and April 2020, and had an AMH level after completion of therapy. We used multivariable linear regressions to compare AMH-level beta coefficients in patients stratified by gonadotoxic risk, adjusting for leuprolide use. Results: Fifty-two females meeting study eligibility were included, of which 35 received leuprolide. The use of leuprolide was associated with higher post-treatment AMH levels in the lower gonadotoxic risk group (beta 2.74, 95% CI 0.97-4.51; p = 0.004). This association was lost in the higher gonadotoxic risk groups. Conclusions: Leuprolide may have a protective effect on the functional ovarian reserve. However, this is limited by increasing treatment gonadotoxicity. Larger, prospective studies are needed to elucidate the potential benefits of gonadotropin-releasing hormone agonist on preservation of ovarian reserve among children receiving gonadotoxic therapies, as cancer survivors.

Preferences for survivorship education and delivery among Latino and non-Latino childhood cancer survivors and caregivers

PURPOSE

To assess survivor and parent perceptions of the long-term survivor visit and preferences regarding accessing health information, survivorship education, and support networks in rural and metropolitan regions of Texas.

METHODS

Leveraging the multi-institutional Survivorship and Access to Care for Latinos to Understand Disparities (SALUD) cohort, we administered a 26-item bilingual survey to adult survivors of childhood cancer and parents of younger survivors. Characteristics and responses were compared between survivors vs. parents and Latinos vs. non-Latinos using a t test or Fisher exact test. Odds ratios for the outcomes of interest were calculated with 95% confidence intervals.

RESULTS

We received 138 responses from 59 survivors and 79 parents of survivors treated at three Texas pediatric cancer hospitals/clinics. Parents were more likely than survivors to seek survivorship information from other survivors or parents of survivors (OR=6.32, 95% CI 1.78, 22.47), and non-Latinos preferred social media as an educational resource (OR=3.70, CI 1.58, 8.68). Survivors, particularly Latino survivors, preferred short videos as a mode of survivorship education delivery. Highest topic priorities for survivorship education were 'risk for second cancers' and 'diet, nutrition, and exercise.' All parents and survivors who rated survivor physical and mental health as 'fair' or 'poor' identified as Latino.

CONCLUSIONS

These results highlight differences in perceived health status between Latino and non-Latino survivors and support the development of adapted survivorship education content to address the specific needs of Latino survivors. Implications for Cancer Survivors Results of this study suggest a need for survivorship educational materials in multiple formats and that are tailored to the style, content, language preferences, and health literacy status of the target population.

The role of surgery in recurrent ependymomas

OBJECTIVE

The role of surgery in recurrent ependymomas and its contribution to the outcome are not well defined. While gross-total resection (GTR) has shown benefit in newly diagnosed patients with improvement in progression-free survival (PFS), its impact after recurrence is not known. Its role in distant relapses or multiple local recurrences is similarly less well understood. The objective of this study was to investigate whether GTR could prolong survival after recurrence.

METHODS

In this paper, the authors identified patients with ependymomas who underwent surgery at Texas Children's Hospital for recurrent ependymomas between December 2000 and December 2021. Surgical treatment was stratified as GTR, subtotal resection (STR), or a biopsy. Kaplan-Meier analysis was performed for PFS and overall survival (OS), and the log-rank test was used to assess statistical significance. The Cox regression model was used for multivariable analysis.

RESULTS

Forty children were identified with a first ependymoma recurrence and follow-up data were collected. The median age was 5.46 years (95% CI 4.52-6.39 years) with a mean follow-up of 3.92 years (95% CI 2.42-5.42 years). In 26 patients (65%), the original tumor was located in the infratentorial space. Twenty-nine patients (72.5%) presented with local recurrence. Within this group, the 5-year PFS rates for the GTR and STR groups were 40.1% and 26.8%, respectively. The 5- and 10-year OS rates were 58.3% and 50% in the GTR group and 51% and 16.7% in the STR group, respectively. Fifteen patients presented with a second recurrence. The 5-year PFS and OS rates in patients who had GTR after a second recurrence were 33% and 50%, respectively.

CONCLUSIONS

GTR of local recurrent ependymomas can result in long-term survival in first and second recurrences. Further and larger studies are necessary to elucidate the role of surgery in distal recurrences.

The role of neoadjuvant chemotherapy in the management of metastatic central nervous system germinoma: A meta-analysis

BACKGROUND

The role of neoadjuvant chemotherapy in treating patients with metastatic central nervous system (CNS) germinoma is controversial.

METHODS

We compared the relapse-free survival (RFS) of different treatment modalities by performing a meta-analysis using published data. We summarized all data using standard descriptive statistics. We used the Kaplan-Meier method to estimate RFS and their corresponding 95% confidence intervals (CIs). We used the log-rank test for the comparison of survival functions.

RESULTS

We identified 97 patients with a median age at presentation of 15 years (range: 7-38). Sites of metastasis were cerebrospinal fluid (CSF) disease only (n = 12), brain parenchyma (n = 18), spinal cord (n = 9), ventricular and CSF (n = 10), ventricular only (n = 31), and other (n = 17). The 3-year RFS among patients who received any form of radiotherapy was 89% (95% CI: 83-96) compared with 0% for patients who received a chemotherapy-only regimen (p = .001). Five-year RFS among patients who received craniospinal irradiation (CSI) was 92% (95% CI: 84-100) compared with 76.4% (95% CI: 63-90) in the non-CSI group (with or without neoadjuvant chemotherapy) (p = .014). Five-year RFS of patients who received CSI less than 24 Gy with neoadjuvant chemotherapy was 100% compared with 92% (95% CI: 83-100) CSI dose greater than or equal to 24 Gy alone (p = .3).

CONCLUSIONS

Our analysis does not support avoiding spinal irradiation among patients with radiographic metastatic CNS germinoma. Future studies are needed to confirm whether neoadjuvant chemotherapy will allow a reduction of irradiation dose without compromising survival.

Management of nutritional iron deficiency anemia for young children in the emergency department

BACKGROUND

Guidelines for young children with nutritional iron deficiency anemia (IDA) presenting to the emergency department (ED) are lacking, leading to variability in care. We aimed to standardize management of these patients through the development and implementation of an evidence-based algorithm using quality improvement methodology.

PROCEDURE

Baseline data of the target population (n = 42; 60% male; median age 22.5 months, median hemoglobin 5.3 g/dl) identified variability across four key measures of clinical management: laboratory evaluation, therapy choice, therapy administration, and patient disposition. Literature review and consensus from pediatric hematology providers informed a draft algorithm that was refined in an iterative multidisciplinary process. From September 2020 to June 2021, we aimed to increase IDA management per the algorithm by ≥20% relative to baseline for the four key outcome measures using sequential Plan-Do-Study-Act (PDSA) cycles. Process measures focusing on provider communication/documentation and balancing measures involving efficiency and therapy-related adverse events were assessed concurrently.

RESULTS

Thirty-five patients were evaluated among four PDSA cycles and shared similar characteristics as the baseline population. Improvements of ≥20% above baseline adherence levels or 100% adherence were achieved for all outcome measure across four PDSA cycles. Adherence to recommended laboratory evaluation improved from 43 (baseline) to 71%, therapy choice from 78 to 100%, therapy administration from 50 to 83%, and disposition from 85 to 100%. ED length of stay remained stable.

CONCLUSIONS

Implementation of a standardized algorithm for young children with nutritional IDA in the ED increased adherence to evidence-based patient care.

Comparison of neurocognitive and quality-of-life outcomes in pediatric craniopharyngioma patients treated with partial resection and radiotherapy versus gross-total resection only

OBJECTIVE

The optimal management of pediatric craniopharyngioma patients remains controversial, shifting from radical resection (gross-total resection [GTR]) to a more conservative approach with partial resection/biopsy followed by radiotherapy (PR+RT). To the authors' knowledge, no previous studies have compared neurocognitive and quality-of-life (QOL) outcomes between the two main treatments. In this study, the authors compared changes in intellectual, adaptive, and QOL scores in children treated for craniopharyngioma with GTR and those treated with PR+RT.

METHODS

Patients underwent annual neurocognitive and QOL evaluations for up to 10 years posttreatment, including the Full-Scale IQ, Verbal Comprehension Index (VCI), Perceptual Reasoning Index (PRI), Working Memory Index (WMI), and Processing Speed Index (PSI). Child- and parent-reported QOL scores and adaptive behavior in different domains were assessed. General linear mixed models were used to examine change in scores over time by treatment group with adjustment for significant covariates.

RESULTS

Scores from 43 patients treated between 2009 and 2019 (21 GTR, 22 PR+RT) were examined. Within the PR+RT group, 9 patients had intensity-modulated RT and 13 had proton beam therapy. The treatment groups were similar in sex (44% male) and age (median 7.3 years). There were no significant differences in the trajectory of intellectual functioning or QOL scale scores between the two groups. However, patients who underwent GTR exhibited significant improvement over time in overall adaptive behavior (p = 0.04) and conceptual skills (p = 0.01), which was not observed in patients treated with PR+RT.

CONCLUSIONS

Long-term pediatric craniopharyngioma survivors treated with GTR and PR+RT have similar intellectual function and QOL. Larger studies are needed to explore small but clinically significant differences between the two groups.

Superior verbal learning and memory in pediatric brain tumor survivors treated with proton versus photon radiotherapy

OBJECTIVE

Radiotherapy for pediatric brain tumor has been associated with late cognitive effects. Compared to conventional photon radiotherapy (XRT), proton radiotherapy (PRT) delivers lower doses of radiation to healthy brain tissue. PRT has been associated with improved long-term cognitive outcomes compared to XRT. However, there is limited research comparing the effects of XRT and PRT on verbal memory.

METHOD

Survivors of pediatric brain tumor treated with either XRT (n = 29) or PRT (n = 51) completed neuropsychological testing > 1 year following radiotherapy. Performance on neuropsychological measures was compared between treatment groups using analysis of covariance. Chi-squared tests of independence were used to compare the frequency of encoding, retrieval, and intact memory profiles between treatment groups. Associations between memory performance and other neurobehavioral measures were examined using Pearson correlation.

RESULTS

Overall, patients receiving PRT demonstrated superior verbal learning and recall compared to those treated with XRT. Encoding and retrieval deficits were more common in the XRT group than the PRT group, with encoding problems being most prevalent. The PRT group was more likely to engage in semantic clustering strategies, which predicted better encoding and retrieval. Encoding ability was associated with higher intellectual and adaptive functioning, and fewer parent-reported concerns about day-to-day attention and cognitive regulation.

CONCLUSION

Results suggest that PRT is associated with verbal memory sparing, driven by effective encoding and use of learning strategies. Future work may help to clarify underlying neural mechanisms associated with verbal memory decline, which will better inform treatment approaches. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

RADT-36. MANAGEMENT OF PATIENTS WITH METASTATIC CENTRAL NERVOUS SYSTEM (CNS) GERMINOMA; A LITERATURE REVIEW

BACKGROUND

No consensus exists on the optimal irradiation volume/dose for patients with metastatic CNS germinoma. We reviewed the literature for a potential association between different treatment modalities and survival.

METHODS

We searched PubMed for studies on patients with primary metastatic CNS germinoma including detailed survival outcome data. We used the Kaplan-Meier method to estimate event-free survival (EFS) rates and log-rank test for comparison among treatment modalities.

RESULTS

We identified 124 patients from 38 studies published between 1990 and 2021. The median age of presentation was 15 years (range: 1.5–47 years). Treatment modalities included: chemotherapy only (n = 5), radiotherapy only (n = 31), and radio-chemotherapy (n = 88). Radiotherapy modalities included: craniospinal irradiation (CSI) (n = 69), whole-brain irradiation (WBI) (n = 19), whole ventricular irradiation (WVI) (n=16), focal and spine irradiation (n = 5), focal irradiation only (n = 9), and not specified (n = 1). The median focal irradiation dose was 36.6 Gy (range:19.5-59.8 Gy). The median doses for CSI, WBI, and WVI were 24 Gy (range: 10.8-49 Gy). Eighteen patients relapsed, 111 were alive without disease, 2 were alive with disease, and 12 died of disease. The median follow-up time was 5 years in survivors. Four patients who received only chemotherapy relapsed. Five-year EFS rates were similar in patients who received chemo-radiotherapy and radiotherapy alone (89%, 95%CI 81-97%, vs 88%, 95%CI 74-100%, p = 0.6). Patients who were treated with CSI had a longer 5-year EFS compared to patients treated with other modalities (92%, 95%CI 84-100% vs 80%, 95%CI 64-94% p = 0.03). EFS was similar in patients treated with CSI whether they received ≥ 24 Gy or less.

CONCLUSION

CSI is required to achieve prolonged relapse-free survival (RFS). CSI dose of &lt; 24 Gy may be sufficient to achieve sustained RFS. Future trials are needed to evaluate the potential role of neoadjuvant chemotherapy in reducing the dose/volume of irradiation in patients with metastatic CNS germinoma.

Predicting neurocognitive function in pediatric brain tumor early survivorship: The neurological predictor scale and the incremental validity of tumor size

BACKGROUND

The Neurological Predictor Scale (NPS) quantifies cumulative exposure to conventional treatment-related neurological risks but does not capture potential risks posed by tumors themselves. This study evaluated the predictive validity of the NPS, and the incremental value of tumor location and size, for neurocognitive outcomes in early survivorship following contemporary therapies for pediatric brain tumors.

PROCEDURE

Survivors (N = 69) diagnosed from 2010 to 2016 were administered age-appropriate versions of the Wechsler Intelligence Scales. Hierarchical multiple regressions examined the predictive and incremental validity of NPS score, tumor location, and tumor size.

RESULTS

Participants (51% female) aged 6-20 years (M = 13.22, SD = 4.09) completed neurocognitive evaluations 5.16 years (SD = 1.29) postdiagnosis. The NPS significantly predicted Full-Scale Intelligence Quotient (FSIQ; ΔR2  = .079), Verbal Comprehension Index (VCI; ΔR2  = 0.051), Perceptual Reasoning Index (PRI; ΔR2  = 0.065), and Processing Speed Index (PSI; ΔR2  = 0.049) performance after controlling for sex, age at diagnosis, and maternal education. Tumor size alone accounted for a significant amount of unique variance in FSIQ (ΔR2  = 0.065), PRI (ΔR2  = 0.076), and PSI (ΔR2  = 0.080), beyond that captured by the NPS and relevant covariates. Within the full model, the NPS remained a significant independent predictor of FSIQ (β = -0.249, P = 0.016), VCI (β = -0.223, P = 0.048), and PRI (β = -0.229, P = 0.037).

CONCLUSIONS

Tumor size emerged as an independent predictor of neurocognitive functioning and added incrementally to the predictive utility of the NPS. Pretreatment disease burden may provide one of the earliest markers of neurocognitive risk following contemporary treatments. With perpetual treatment advances, measures quantifying treatment-related risk may need to be updated and revalidated to maintain their clinical utility.

Cerebellar Mutism Syndrome in Pediatric Neuro-oncology: A Multidisciplinary Perspective and Call for Research Priorities

Cerebellar mutism syndrome (CMS), also known as posterior fossa syndrome, occurs in a subset of children after posterior fossa tumor resection, most commonly medulloblastoma. Patients with this syndrome exhibit often transient, although protracted, symptoms of language impairment, emotional lability, cerebellar, and brainstem dysfunction. However, many patients experience persistent neurological deficits and lasting neurocognitive impairment. Historically, research and clinical care were hindered by inconsistent nomenclature, poorly defined diagnostic criteria, and uncertainty surrounding risk factors and etiology. Proposed diagnostic criteria include two major symptoms, language impairment and emotional lability, as proposed by the international Board of the Posterior Fossa Society in their consensus statement as well as other experts in this field. Risk factors most commonly associated with development of CMS include midline tumor location, diagnosis of medulloblastoma and specific tumor subtype, younger age at diagnosis, and preoperative language impairment. A proposed etiology of CMS includes disruption of the cerebellar outflow tracts, the cerebellar nuclei, and their efferent projections through the superior cerebellar peduncle. Treatment for CMS remains supportive. Herein, we present a comprehensive overview of CMS etiology, diagnosis, risk factors, clinical presentation, and clinical management. In addition, we identify essential multidisciplinary research priorities to advance diagnostics, prevention, and intervention efforts for patients with, or at risk for, development of CMS.

LGG-04. Clinical and molecular characterization of metastatic pediatric low grade gliomas

BACKGROUND: Despite being the most common central nervous system tumor in children, ≤5% of pediatric low grade gliomas (pLGG) present with metastases. Due to their rarity, there is a paucity of clinical and molecular data in metastatic pLGGs. To address the need, we analyzed a cohort of 22 patients with pLGG followed at Texas Children’s Hospital who presented with metastatic disease. RESULTS: The predominant histology was pilocytic astrocytoma (16/22, 73%); average age at diagnosis was 4 years 11 months. The most common sites of primary disease were optic pathway/chiasm (7/22, 32%) and suprasellar (5/22, 23%). Metastatic disease was most commonly noted in the leptomeninges (12/22, 55%). 16/22 patients (73%) were treated with up-front medical therapy following tumor biopsy/resection, the majority with carboplatin-based therapy; the remaining 6 patients received only surgery up-front. Only 2/22 patients (9%) did not progress after their initial treatment with an average follow-up of 42 months. 14 patients (14/22, 64%) had continued disease progression after at least 2 therapeutic interventions; however, only 3 patients (3/22, 14%) eventually received craniospinal radiation. 10 patients (10/22, 45%) received treatment with an agent targeting the mitogen-activated protein kinase (MAPK) pathway. 20/22 patients (91%) were alive at last follow-up (average 72 months). 4/21 patients (19%) harbored a BRAF V600E mutation while 7/20 (35%) had a BRAF::KIAA1549 duplication/fusion. 8/20 patients (40%) were wildtype for both analyzed molecular alterations in BRAF. 8 patients had germline whole exome sequencing performed and all were negative for pathogenic/likely-pathogenic variants related to their clinical phenotype. Methylation analyses are pending on patients with available tumor tissue. CONCLUSION: In our cohort of patients with metastatic pLGG, most tumors progressed despite numerous therapeutic regimens, but the overall survival was >90%. 40% of patients were wild type for the 2 most common MAPK alterations seen in pLGG.

LGG-15. Late mortality and morbidity of adult survivors of childhood glioma treated across three decades: a report from the Childhood Cancer Survivor Study

PURPOSE: Pediatric low-grade glioma therapy has evolved to delay or eliminate radiation. The impact of therapy changes on long-term outcomes remains unknown. METHODS: Cumulative incidence of late mortality (death >5 years from diagnosis), subsequent neoplasms (SNs), and chronic health conditions (CHCs, CTCAE grading criteria) were evaluated in the Childhood Cancer Survivor Study among 5-year survivors of glioma diagnosed 1970-1999. Outcomes were evaluated by diagnosis decade and by treatment exposures received ≤5 years following diagnosis (surgery-only, chemotherapy ± surgery, and cranial radiation ± surgery or chemotherapy). Relative risk (RRs) with 95%CIs estimated long-term outcomes using multivariable piecewise exponential models. RESULTS: Among 2,684 eligible survivors (age at diagnosis (median [range]), 7 years [0-20 years]; time from diagnosis, 24 years [5-48 years]), exposure to cranial radiation decreased [51% (1970s), 45% (1980s), 25% (1990s)] along with late tumor recurrence (>5 & ≤15 years from diagnosis) [9.8% (1970s), 8.8% (1980s), 5.0% (1990s)]. The 15-year cumulative incidence of late mortality was 10.3% (1970s), 6.5% (1980s), and 6.0% (1990s) (p<0.001, comparison of cumulative incidence curves). The 15-year cumulative incidence of grade 3-5 CHCs was 19.7% (1970s), 17.8% (1980s), and 14.2% (1990s) (p<0.0001). A reduction in SN incidence was not observed. In multivariable analyses excluding treatment exposure, later diagnosis (1990s vs. 1970s) was associated with lower risk of late mortality, grade 3-5 CHCs and SNs. Inclusion of treatment exposure in the model attenuated the effect of diagnosis decade. Radiation or chemotherapy exposure increased risk compared to surgery alone for late mortality (radiation RR 4.95, 95%CI 3.79-6.47; chemotherapy RR 2.88, 95%CI 1.85-4.48), CHCs (radiation RR 4.02, 95%CI 3.28-4.94; chemotherapy RR 1.66, 95%CI 1.13-2.45), and SNs (radiation RR 4.02, 95%CI 3.06-6.13, chemotherapy RR 2.08, 95%CI 1.03-4.23)). CONCLUSION: Late mortality and CHCs decreased in childhood glioma survivors diagnosed from 1970-1999 largely due to therapy changes, particularly avoidance of cranial radiation, without increased late recurrence.

Cognitive predictors of social adjustment in pediatric brain tumor survivors treated with photon versus proton radiation therapy

BACKGROUND

Pediatric brain tumor survivors are at risk for poor social outcomes. It remains unknown whether cognitive sparing with proton radiotherapy (PRT) supports better social outcomes relative to photon radiotherapy (XRT). We hypothesized that survivors treated with PRT would outperform those treated with XRT on measures of cognitive and social outcomes. Further, we hypothesized that cognitive performance would predict survivor social outcomes.

PROCEDURE

Survivors who underwent PRT (n = 38) or XRT (n = 20) participated in a neurocognitive evaluation >1 year post radiotherapy. Group differences in cognitive and social functioning were assessed using analysis of covariance (ANCOVA). Regression analyses examined predictors of peer relations and social skills.

RESULTS

Age at evaluation, radiation dose, tumor diameter, and sex did not differ between groups (all p > .05). XRT participants were younger at diagnosis (XRT M = 5.0 years, PRT M = 7.6 years) and further out from radiotherapy (XRT M = 8.7 years, PRT M = 4.6 years). The XRT group performed worse than the PRT group on measures of processing speed (p = .01) and verbal memory (p < .01); however, social outcomes did not differ by radiation type. The proportion of survivors with impairment in peer relations and social skills exceeded expectation; χ² (1) = 38.67, p < .001; χ² (1) = 5.63, p < .05. Household poverty predicted peer relation difficulties (t = 2.18, p < .05), and verbal memory approached significance (t = -1.99, p = .05). Tumor diameter predicted social skills (t = -2.07, p < .05).

CONCLUSIONS

Regardless of radiation modality, survivors are at risk for social challenges. Deficits in verbal memory may place survivors at particular risk. Results support monitoring of cognitive and social functioning throughout survivorship, as well as consideration of sociodemographic risk factors.

Rising drug cost impacts on cost-effectiveness of 2 chemotherapy regimens for intermediate-risk rhabdomyosarcoma: A report from the Children's Oncology Group

BACKGROUND

The Children's Oncology Group clinical trial for intermediate risk rhabdomyosarcoma randomized participants to a combination of vincristine, dactinomycin, and cyclophosphamide (VAC) alone or VAC alternating with vincristine plus irinotecan (VAC/VI). Clinical outcomes were similar, but toxicity profiles differed. This study estimates the cost differences between arms from the health care system's perspective.

METHODS

A decision-analytic model was used to estimate the incremental cost-effectiveness ratio (ICER) of VAC versus VAC/VI. Protocol-required or recommended medications and laboratory studies were included. Costs were obtained from national databases or supporting literature and inflated to 2019 US dollars. Demographic and outcome data were obtained from the clinical trial and directed chart reviews. Life-years (LY) were estimated from life-expectancy tables and discounted by 3% annually. Probabilistic sensitivity analyses and alternative clinical scenarios identified factors driving costs.

RESULTS

Mean direct medical costs of VAC and VAC/VI were $164,757 and $102,303, respectively. VAC was associated with an additional 0.97 LY and an ICER of $64,386/LY compared with VAC/VI. The ICER was sensitive to survival estimations and to alternative clinical scenarios including outpatient cyclophosphamide delivery (ICER $49,037/LY) or substitution of alternative hematopoietic growth factor schedules (ICER $73,191-$91,579/LY). Applying drug prices from 2012 decreased the total costs of VAC by 20% and VAC/VI by 15% because of changes in dactinomycin and pegfilgrastim prices.

CONCLUSIONS

Neither arm was clearly more cost-effective. Pharmaceutical pricing and location of treatment drove costs and may inform future treatment decisions. Rising pharmaceutical costs added $30,000 per patient, a finding important for future drug-pricing policy decisions.

LAY SUMMARY

Two chemotherapy regimens recently tested side-by-side for rhabdomyosarcoma had similar tumor outcomes, but different side effects. The health care costs of each regimen were compared; neither was clearly more cost-effective. However, the costs of each treatment changed dramatically with choices of supportive medicines and location of treatment. Costs of treatment rose by 15% to 20% because of rising US drug costs not associated with the clinical trial.

Gadolinium is not necessary for surveillance MR imaging in children with chiasmatic-hypothalamic low-grade glioma

BACKGROUND

Patients with chiasmatic-hypothalamic low-grade glioma (CHLGG) have frequent MRIs with gadolinium-based contrast agents (GBCA) for disease monitoring. Cumulative gadolinium deposition in the brains of children is a potential concern. The purpose of this study is to evaluate whether MRI with GBCA is necessary for determining radiographic tumor progression in children with CHLGG.

METHODS

Children who were treated for progressive CHLGG from 2005 to 2019 at Texas Children's Cancer Center were identified. Pre- and post-contrast MRI sequences were separately reviewed by one neuroradiologist who was blinded to the clinical course. Three dimensional measurements and tumor characteristics were evaluated. Radiographic progression was defined as a 25% increase in size (product of two largest dimensions) compared with baseline or best response after initiation of therapy.

RESULTS

A total of 28 patients with progressive CHLGG were identified with a total of 683 MRIs with GBCA reviewed (mean 24 MRIs/patient; range, 11-43 MRIs). Radiographic progression was observed 92 times, 91 (99%) on noncontrast and 90 (98%) on contrast imaging. Sixty-seven progressions necessitating management changes were identified in all (100%) noncontrast sequences and 66 (99%) contrast sequences. Tumor growth > 2 mm in any dimension was identified in 184/187 (98%) noncontrast and 181/187 (97%) with contrast imaging. Metastatic tumors were better visualized on contrast imaging in 4/7 (57%).

CONCLUSION

MRI without GBCA effectively identifies patients with progressive disease. When imaging children with CHLGG, eliminating GBCA should be considered unless monitoring patients with metastatic disease.

Long-term cognitive and academic outcomes among pediatric brain tumor survivors treated with proton versus photon radiotherapy

BACKGROUND

Proton radiotherapy (PRT) may be associated with less neurocognitive risk than photon RT (XRT) for pediatric brain tumor survivors. We compared neurocognitive and academic outcomes in long-term survivors treated with XRT versus PRT.

METHODS

Survivors underwent neurocognitive evaluation >1 year after craniospinal (CSI) or focal PRT or XRT. Groups were compared using separate one-way analyses of covariance for the CSI and focal groups.

RESULTS

PRT (n = 58) and XRT (n = 30) subgroups were similar on gender (66% male), age at RT (median = 6.5 years), age at follow-up (median = 14.6 years), and government assistance status (32%). PRT and XRT focal groups differed on follow-up interval, shunt history, and total RT dose (all p < .05), whereas PRT and XRT CSI groups differed on follow-up interval, baseline neurocognitive performance score, boost volume, and CSI dose (all p < .05). The PRT focal group outperformed the XRT focal group on inhibition/switching (p = .04). The PRT CSI group outperformed the XRT CSI group on inattention/impulsivity (both p < .05). Several clinical variables (i.e., RT dose, boost field, baseline performance) predicted neurocognitive outcomes (all p < .05). The PRT focal group performed comparably to population means on most neurocognitive measures, while both CSI groups performed below expectation on multiple measures. The XRT CSI group was most impaired. All groups fell below expectation on processing speed, fine motor, and academic fluency (most p < .01).

CONCLUSIONS

Findings suggest generally favorable neurocognitive and academic long-term outcomes following focal PRT. Impairment was greatest following CSI regardless of modality. Dosimetry and baseline characteristics are important determinants of outcome alone or in combination with modality.

Treatment age and neurocognitive outcomes following proton beam radiotherapy for pediatric low- and intermediate-grade gliomas

The relationship between age and neurocognitive functioning following proton beam radiotherapy (PRT) in low- and intermediate-grade gliomas (LIGG) has yet to be examined. Eighteen LIGG patients treated with PRT were prospectively enrolled and received annual neurocognitive evaluations of perceptual/verbal reasoning, working memory, and processing speed postradiotherapy. The median age at diagnosis was 8.2 years (range 1.0-14.7) and the median age at PRT was 9.9 years (range 4.2-17.0). Patients' neurocognitive performance did not change on any measure following PRT (p ≥ .142). We did not observe significant changes in cognitive function over time among a small group of LIGG patients treated with PRT.

Disease Control and Patterns of Failure After Proton Beam Therapy for Rhabdomyosarcoma

PURPOSE

Pediatric patients with rhabdomyosarcoma (RMS) are treated with multimodal therapy, often with radiation therapy (RT) as part of local therapy. We report on the efficacy and patterns of failure after proton beam therapy (PBT) for RMS.

METHODS AND MATERIALS

Between January 2006 and February 2017, patients with RMS were enrolled in a prospective institutional review board-approved registry protocol for pediatric patients undergoing PBT. Demographics, clinical characteristics, and treatment related outcomes were reviewed.

RESULTS

Ninety-four RMS patients were treated with a combination of chemotherapy (CT) and PBT. The majority of patients had head and neck (49%) and genitourinary (30%) primaries. Median tumor size was 4.1 cm (range, 1.0-16.5 cm); 33 patients (35%) had primary tumors >5 cm. Median cyclophosphamide equivalent dose was 14.4 g/m² (range, 0-30.8 g/m²). Median time from CT initiation to RT initiation was 13 weeks (range, 1-58 weeks). With median follow-up of 4 years, 4-year overall survival (OS) was 71%, and 4-year progression-free survival (PFS) was 63%. Thirty patients (32%) experienced relapse (13% with local failure [LF]). Four-year local control (LC) was 85% overall; 4-year LC rates were 100% for low-risk, 85% for intermediate-risk, and 55% for high-risk patients (P = .02). Tumor size predicted LC (P = .007), with 7% versus 33% LF rate by tumor size (≤5 cm vs >5 cm). Delayed RT delivery (≥13 weeks from initiation of CT) predicted worse LC (P = .01). Increased tumor size predicted both inferior PFS (P = .02) and OS (P = .01). Delayed RT delivery predicted both inferior PFS (P = .04) and OS (P = .03).

CONCLUSIONS

PBT provides LC comparable to prior studies using photon RT. Inferior LC, PFS, and OS rates were observed for patients with larger tumors and those treated with delayed RT. This finding supports ongoing prospective efforts to dose-escalate treatment of tumors >5 cm; however, these data call into question the optimal timing of local therapy, particularly for patients treated with reduced-dose cyclophosphamide.

Overall survival and secondary malignant neoplasms in children receiving passively scattered proton or photon craniospinal irradiation for medulloblastoma

BACKGROUND

Both intensity-modulated radiotherapy (RT) and passively scattered proton therapy have a risk of secondary malignant neoplasm (SMN) in children. To determine the influence of RT modality on the incidence of SMN after craniospinal irradiation (CSI), the authors compared the incidence of SMN in children who had medulloblastoma treated with either photon CSI plus an intensity-modulated RT boost (group I) or passively scattered proton CSI plus a boost (group II).

METHODS

From 1996 to 2014, 115 children with medulloblastoma (group I, n = 63; group II, n = 52) received CSI followed by a boost to the tumor bed. Most patients had standard-risk disease (63.5%). The median follow-up was 12.8 years for group I and 8.7 years for group II.

RESULTS

The 5-year and 10-year overall survival (OS) rates were 88.8% and 85.1%, respectively, for standard-risk patients and 63.1% and 57.3%, respectively, for high-risk patients, with no OS difference by RT modality (P = .81). Six SMNs were identified (4 in group I, 2 in group II). The 5-year and 10-year SMN incidence rates were 1.0% and 6.9%, respectively (0.0% and 8.0%, respectively, in group I; 2.2% and 4.9%, respectively, in group II; P = .74). Two SMNs occurred in the clinical target volume in the brain, 2 occurred in the exit dose region from the photon spinal field, 1 occurred in the entrance path of a proton beam, and 1 occurred outside the radiation field. There were no reported cases of secondary leukemia.

CONCLUSIONS

This analysis demonstrates no difference in OS or SMN incidence between patients in groups I and II 10 years after RT.

LAY SUMMARY

One hundred fifteen children with medulloblastoma received radiotherapy (RT) with either photon craniospinal irradiation (CSI) and an intensity-modulated RT boost (group I; n = 63) or passively scattered proton CSI and a boost (group II;, n = 52). The majority of children had standard-risk disease (63.5%). The 5-year and 10-year overall survival rates were 88.8% and 85.1% for standard-risk patients, respectively, and 63.1% and 57.3% for high-risk patients, respectively, with no difference in overall survival by RT group (P = .81). The 5-year and 10-year second malignant neoplasm incidence rates were 1.0% and 6.9%, respectively, with no difference in second malignant neoplasm incidence according to RT group (P = .74).

Salivary and Dental Complications in Childhood Cancer Survivors Treated With Radiation Therapy to the Head and Neck: A Pediatric Normal Tissue Effects in the Clinic (PENTEC) Comprehensive Review

PURPOSE

Radiation therapy (RT) to the head and neck (H&N) region is critical in the management of various pediatric malignancies; however, it may result in late toxicity. This comprehensive review from the Pediatric Normal Tissue Effects in the Clinic (PENTEC) initiative focused on salivary dysfunction and dental abnormalities in survivors who received RT to the H&N region as children.

MATERIALS & METHODS

This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method.

RESULTS

Of the 2,164 articles identified through a literature search, 40 were included in a qualitative synthesis and 3 were included in a quantitative synthesis. The dose-toxicity data regarding salivary function demonstrate that a mean parotid dose of 35 to 40 Gy is associated with a risk of acute and chronic grade ≥2 xerostomia of approximately 32% and 13% to 32%, respectively, in patients treated with chemo-radiation therapy. This risk increases with parotid dose; however, rates of xerostomia after lower dose exposure have not been reported. Dental developmental abnormalities are common after RT to the oral cavity. Risk factors include higher radiation dose to the developing teeth and younger age at RT.

CONCLUSIONS

This PENTEC task force considers adoption of salivary gland dose constraints from the adult experience to be a reasonable strategy until more data specific to children become available; thus, we recommend limiting the parotid mean dose to ≤26 Gy. The minimum toxic dose for dental developmental abnormalities is unknown, suggesting that the dose to the teeth should be kept as low as possible particularly in younger patients, with special effort to keep doses <20 Gy in patients <4 years old.

Comparison of multimodal surgical and radiation treatment methods for pediatric craniopharyngioma: long-term analysis of progression-free survival and morbidity

OBJECTIVE

The authors compared survival and multiple comorbidities in children diagnosed with craniopharyngioma who underwent gross-total resection (GTR) versus subtotal resection (STR) with radiation therapy (RT), either intensity-modulated radiation therapy (IMRT) or proton beam therapy (PBT). The authors hypothesized that there are differences between multimodal treatment methods with respect to morbidity and progression-free survival (PFS).

METHODS

The medical records of children diagnosed with craniopharyngioma and treated surgically between February 1997 and December 2018 at Texas Children's Hospital were reviewed. Surgical treatment was stratified as GTR or STR + RT. RT was further stratified as PBT or IMRT; PBT was stratified as STR + PBT versus cyst decompression (CD) + PBT. The authors used Kaplan-Meier analysis to compare PFS and overall survival, and chi-square analysis to compare rates for hypopituitarism, vision loss, and hypothalamic obesity (HyOb).

RESULTS

Sixty-three children were included in the analysis; 49% were female. The mean age was 8.16 years (95% CI 7.08-9.27). Twelve of 14 children in the IMRT cohort underwent CD. The 5-year PFS rates were as follows: 73% for GTR (n = 31), 54% for IMRT (n = 14), 100% for STR + PBT (n = 7), and 77% for CD + PBT (n = 11; p = 0.202). The overall survival rates were similar in all groups. Rates of hypopituitarism (96% GTR vs 75% IMRT vs 100% STR + PBT, 50% CD + PBT; p = 0.023) and diabetes insipidus (DI) (90% GTR vs 61% IMRT vs 85% STR + PBT, 20% CD + PBT; p = 0.004) were significantly higher in the GTR group. There was no significant difference in the HyOb or vision loss at the end of study follow-up among the different groups. Within the PBT group, 2 patients presented a progressive vasculopathy with subsequent strokes. One patient experienced a PBT-induced tumor.

CONCLUSIONS

GTR and CD + PBT presented similar rates of 5-year PFS. Hypopituitarism and DI rates were higher with GTR, but the rate of HyOb was similar among different treatment modalities. PBT may reduce the burden of hypopituitarism and DI, although radiation carries a risk of potential serious complications, including progressive vasculopathy and secondary malignancy. Further prospective study comparing neurocognitive outcomes is necessary.

Early radiotherapy preserves vision in sporadic optic pathway glioma

BACKGROUND

Sporadic optic pathway/hypothalamic gliomas represent a unique entity within pediatric low-grade glioma. Despite favorable survival, location makes treatment difficult and local progression debilitating. This study is a longitudinal assessment of visual acuity (VA) among children treated within the last 2 decades.

METHODS

Clinical characteristics were abstracted for patients treated from 2000 to 2018 at Texas Children's Cancer Center in Houston. Ophthalmologic data taken at 3- to 6-month intervals were examined with age-appropriate VA metrics converted to the LogMAR (logarithm of the minimum angle of resolution) scale. Kaplan-Meier blindness-free survival (BFS) curves, calculated as time-to-bilateral functional blindness (LogMAR ≥0.8 in both eyes), were calculated for patients receiving early radiation therapy (RT; upfront or as first-line salvage treatment) or chemotherapy (CT) and evaluated using the log-rank test.

RESULTS

Thirty-eight patients with a median follow-up of 8.5 years (range, 2-17 years) were identified. Median age at diagnosis was 3 years (interquartile range, <1-6 years). Early RT was administered in 11 patients (29%). Twenty-seven patients (71%) were treated primarily with CT, initiated at a median age of 3.5 years (range, <1-11 years). Eight patients in the CT group did eventually require RT secondary to VA loss and following multiple lines of CT. Median age at RT for all patients was 11 years (range, 3-17 years). BFS rates were 81% at 5 years and 60% at 8 years for CT and 100% at 5 and 8 years for early RT (P = .017).

CONCLUSIONS

In a contemporary cohort, early RT, defined as initial or first-line salvage therapy, was found to have superior BFS for appropriately selected patients with sporadic optic pathway/hypothalamic gliomas.

LAY SUMMARY

Children with low-grade brain tumors of the optic pathway generally have excellent long-term survival; however, given the location of these tumors, there can commonly be threatened vision if the tumor grows. Although radiation is generally deferred in children on the basis of legitimate concerns regarding the effects on the developing brain, it may represent a vision-preserving therapy for well-selected older patients.

Treatment of central giant cell granuloma in children with denosumab

Central giant cell granuloma (CGCG) is a benign but locally aggressive intraosseous lesion of the mandible. Historically, it is treated by curettage or resection. Medical therapy is indicated when surgery is associated with increased morbidity or in adjuvant setting to decrease recurrence. Treatment of CGCG with denosumab, a receptor activator of nuclear factor kappa-beta (RANK) ligand inhibitor, is not well studied, especially in children. Here, we describe our experience with the use of denosumab in the treatment of six children with CGCG. All patients had a favorable response with manageable side effects, which suggests that denosumab is an effective treatment option without increased morbidity.

Reevaluating surgery and re-irradiation for locally recurrent pediatric ependymoma—a multi-institutional study

Background

The goal of this study was to evaluate extent of surgical resection, and timing and volume of re-irradiation, on survival for children with locally recurrent ependymoma.

Methods

Children with locally recurrent ependymoma treated with a second course of fractionated radiotherapy (RT2) from 6 North American cancer centers were reviewed. The index time was from the start of RT2 unless otherwise stated.

Results

Thirty-five patients were included in the study. The median doses for first radiation (RT1) and RT2 were 55.8 and 54 Gy, respectively. Median follow-up time was 5.6 years. Median overall survival (OS) for all patients from RT2 was 65 months. Gross total resection (GTR) was performed in 46% and 66% of patients prior to RT1 and RT2, respectively. GTR prior to RT2 was independently associated with improved progression-free survival (PFS) for all patients (HR 0.41, P = 0.04), with an OS benefit (HR 0.26, P = 0.03) for infratentorial tumors. Median PFS was superior with craniospinal irradiation (CSI) RT2 (not reached) compared to focal RT2 (56.9 months; log-rank P = 0.03). All distant failures (except one) occurred after focal RT2. Local failures after focal RT2 were predominantly in patients with less than GTR pre-RT2.

Conclusions

Patients with locally recurrent pediatric ependymoma should be considered for re-treatment with repeat maximal safe resection (ideally GTR) and CSI re-irradiation, with careful discussion of the potential side effects of these treatments.

QOL-01. LONGITUDINAL COMPARISON OF NEUROCOGNITIVE TRAJECTORIES IN PEDIATRIC MEDULLOBLASTOMA PATIENTS TREATED WITH PROTON VERSUS PHOTON RADIOTHERAPY

PURPOSE

By reducing dose to normal brain tissue, proton radiotherapy (PRT) may lessen neurocognitive risk traditionally associated with photon radiotherapy (XRT). We examined change in neurocognitive scores over time in pediatric medulloblastoma patients treated with PRT versus XRT.

METHODS

Neurocognitive scores from 79 patients (37 PRT, 42 XRT) were examined. Patients were treated between 2007–2018 on the same treatment protocols that differed only by craniospinal modality (PRT versus XRT). Change in scores over time since diagnosis were compared between groups.

RESULTS

Groups were similar on most demographic/clinical variables: sex (67.1% male), age at diagnosis (mean 8.6 years), CSI dose (median 23.4 Gy), length of follow-up (mean 4.3 years), and parental education (mean 14.3 years). Boost dose (p<0.001) and margin (p=0.001) differed between groups. Adjusting for covariates, the PRT group exhibited superior outcomes in global IQ, perceptual reasoning, and working memory versus the XRT group (all p<0.05). The XRT group exhibited significant decline in global IQ, working memory, and processing speed (all p<0.05). The PRT group exhibited stable scores in all domains except processing speed (p=0.003). Posterior fossa syndrome imparted risk independent of modality.

CONCLUSION

This is the first study comparing neurocognitive trajectories between pediatric patients treated for medulloblastoma with PRT versus XRT on comparable, contemporary protocols. PRT was associated with more favorable neurocognitive outcomes in most domains compared to XRT, although processing speed emerged as vulnerable in both groups. This is the strongest evidence to date of an intellectual sparing advantage with PRT in the treatment of pediatric medulloblastoma.

RONC-12. TREATMENT AGE AND NEUROCOGNITIVE OUTCOMES FOLLOWING PROTON BEAM RADIOTHERAPY FOR PEDIATRIC LOW GRADE GLIOMA

INTRODUCTION

Younger age at radiotherapy increases cognitive risk for patients with pediatric low grade glioma (LGG). We examined the impact of age at treatment on cognitive trajectories in LGG patients treated with proton radiotherapy (PRT) compared to patients treated without radiotherapy (surgery only; SO).

METHODS

We examined cognitive scores of 48 LGG patients on a prospective, longitudinal study. General linear mixed models evaluated change in cognitive scores over time.

RESULTS

The sample included 16 patients treated with PRT and 32 with SO (median follow-up=3.1 years, range 0.9–6.1). Median age of PRT patients was 8.2 years at diagnosis (range 1.0–14.4) and 9.4 years at PRT (range 4.2–16.7). 13 PRT patients also received surgery: 53.8% biopsy, 30.8% subtotal resection, 15.4% gross total resection. Tumor sites included: 31.2% hypothalamic/suprasellar, 25.0% optic pathway, 18.8% temporal, 25.0% other. Median age of SO patients was 8.2 years at diagnosis (range 2.9–18.6). Surgical outcomes were: 75.0% gross total resection, 21.9% biopsy/other. There were no group differences in diagnosis age, tumor volume, or shunt history (all p>0.05). Both PRT and SO groups displayed stable cognitive functioning over time (all p>0.1). Slopes (i.e., change in scores over time) did not differ between groups (all p>0.1). Age at treatment was not associated with slope or performance at last follow-up in either group (all p>0.05).

CONCLUSIONS

We observed stable cognitive functioning, independent of age at treatment, following PRT for LGG. Outcomes were similar to patients receiving surgery only. Further examination in a larger sample is warranted.

Genetic variation in the body mass index of adult survivors of childhood acute lymphoblastic leukemia: A report from the Childhood Cancer Survivor Study and the St. Jude Lifetime Cohort

BACKGROUND

Treatment characteristics such as cranial radiation therapy (CRT) do not fully explain adiposity risk in childhood acute lymphoblastic leukemia (ALL) survivors. This study was aimed at characterizing genetic variation related to adult body mass index (BMI) among survivors of childhood ALL.

METHODS

Genetic associations of BMI among 1458 adult survivors of childhood ALL (median time from diagnosis, 20 years) were analyzed by multiple approaches. A 2-stage genome-wide association study in the Childhood Cancer Survivor Study (CCSS) and the St. Jude Lifetime Cohort Study (SJLIFE) was performed. BMI was a highly polygenic trait in the general population. Within the known loci, the BMI percent variance explained was estimated, and additive interactions (chi-square test) with CRT in the CCSS were evaluated. The role of DNA methylation in CRT interaction was further evaluated in a subsample of ALL survivors.

RESULTS

In a meta-analysis of the CCSS and SJLIFE, 2 novel loci associated with adult BMI among survivors of childhood ALL (LINC00856 rs575792008 and EMR1 rs62123082; P_Meta < 5E-8) were identified. It was estimated that the more than 700 known loci explained 6.2% of the variation in adult BMI in childhood ALL survivors. Within the known loci, significant main effects for 23 loci and statistical interactions with CRT at 9 loci (P < 7.0E-5) were further identified. At 2 CRT-interacting loci, DNA methylation patterns may have differed by age.

CONCLUSIONS

Adult survivors of childhood ALL have genetic heritability for BMI similar to that observed in the general population. This study provides evidence that treatment with CRT can modify the effect of genetic variants on adult BMI in childhood ALL survivors.

Prospective, longitudinal comparison of neurocognitive change in pediatric brain tumor patients treated with proton radiotherapy versus surgery only

BACKGROUND

Proton radiotherapy (PRT) reduces the volume of normal tissue receiving radiation dose, which may lead to better neurocognitive outcomes. We examined change in neurocognitive scores over time in pediatric brain tumor patients treated with proton craniospinal irradiation (CSI), proton focal RT, or surgery only.

METHODS

Patients received annual neurocognitive evaluations for up to 6 years. We examined Full Scale IQ (FSIQ), Verbal Comprehension Index (VCI), Perceptual Reasoning Index (PRI), Working Memory Index (WMI), and Processing Speed Index (PSI) scores. General linear mixed models examined change in scores over time by treatment group, adjusting for significant covariates.

RESULTS

Scores from 93 patients treated between 2012 and 2017 (22 proton CSI, 31 proton focal, and 40 surgery only) were examined. Treatment groups were similar on gender (51.6% male), age at treatment (median = 9.7 y), and length of follow-up (median = 2.9 y). The surgery only group had proportionately more gliomas (P < 0.001), and the proton CSI group had more infratentorial tumors (P = 0.001) and higher total RT dose (P = 0.004). The proton focal and surgery only groups exhibited stable neurocognitive scores over time across all indexes (all P > 0.05). In the proton CSI group, WMI, PSI, and FSIQ scores declined significantly (P = 0.036, 0.004, and 0.017, respectively), while VCI and PRI scores were stable (all P > 0.05).

CONCLUSIONS

Focal PRT was associated with stable neurocognitive functioning into survivorship. Outcomes were similar whether patients received focal PRT or no radiotherapy, even in neurocognitive domains known to be particularly radiosensitive. Proton CSI emerged as a neurocognitive risk factor, consistent with photon outcomes research.

Late morbidity and mortality in adult survivors of childhood glioma with neurofibromatosis type 1: report from the Childhood Cancer Survivor Study

Purpose

Neurofibromatosis type 1 (NF1) is associated with tumor predisposition and non-malignant health conditions. Whether survivors of childhood cancer with NF1 are at increased risk for poor long-term health outcomes is unknown.

Methods

147 5+ year survivors of childhood glioma with NF1 from the Childhood Cancer Survivor Study were compared to 2 629 non-NF1 glioma survivors and 5 051 siblings for late mortality, chronic health conditions, psychosocial, neurocognitive, and socioeconomic outcomes.

Results

Survivors with NF1 (age at diagnosis: 6.8±4.8 years) had greater cumulative incidence of late mortality 30 years after diagnosis (46.3%[95% confidence interval: 23.9%−62.2%]) compared to non-NF1 survivors (18.0%[16.1%−20.0%]) and siblings (0.9%[0.6%−1.2%]), largely due to subsequent neoplasms. Compared to survivors without NF1, those with NF1 had more severe/life-threatening chronic conditions at cohort entry (46.3%[38.1%−54.4%] vs. 30.8%[29.1%−32.6%]), but similar rates of new conditions during follow-up (Rate Ratio: 1.26 [0.90–1.77]). Survivors with NF1 were more likely to report psychosocial impairments, neurocognitive deficits, and socioeconomic difficulties compared to survivors without NF1.

Conclusion

Late mortality among glioma survivors with NF1 is twice that of other survivors, due largely to subsequent malignancies. Screening, prevention and early intervention for chronic health conditions, psychosocial and neurocognitive deficits may reduce long-term morbidity in this vulnerable population.

Cognitive mediators of adaptive functioning outcomes in survivors of pediatric brain tumors treated with proton radiotherapy

BACKGROUND

Cranial radiotherapy (RT) is associated with risk for cognitive and adaptive dysfunction. Proton RT (PRT) is a technique hypothesized to spare cognition by reducing exposure to nontarget brain tissue. However, little is known regarding functional outcomes in survivors of pediatric brain tumor (BT) treated with PRT. The present study examined the relationship between cognitive and adaptive outcomes in pediatric BT survivors post-PRT.

METHODS

Survivors treated with either focal (n = 33) or craniospinal irradiation (CSI; n = 37) PRT completed neurocognitive evaluations approximately 5 years post-treatment. Results of intelligence testing and ratings of adaptive functioning are reported. Mediation models examined the relationship among radiation field, cognition, and adaptive functioning.

RESULTS

The PRT CSI group demonstrated worse cognitive outcomes than the PRT Focal group across each cognitive index (Cohen's d = 0.56-0.70). Parent ratings of adaptive functioning were also worse in the PRT CSI group than the PRT Focal group (Global Adaptive Composite, d = 0.53; conceptual skills, d = 0.67). Cognitive performance fully mediated the relationship between radiation field and adaptive outcomes, while controlling for group differences in tumor histology and RT dose.

CONCLUSIONS

Focal PRT survivors demonstrated generally positive outcomes with weaknesses in processing speed and aspects of adaptive functioning. CSI exposure was associated with more consistently poor cognitive and adaptive outcomes. The increased risk for adaptive dysfunction in the PRT CSI group appeared due to the effects of CSI on cognition. Efforts to reduce the volume of tissue exposure to RT remain important.

Neuropsychological functioning following surgery for pediatric low-grade glioma: a prospective longitudinal study

OBJECTIVE

High survival rates have led to an increased emphasis on the functional outcomes of children diagnosed with low-grade glioma. Most outcomes research has focused on risks associated with radiotherapy, but less is known about neuropsychological risks for patients treated with surgery alone. Here, the authors sought to examine the neuropsychological trajectories of children diagnosed with a low-grade glioma and monitored up to 6 years postsurgery. Secondarily, they explored demographic and clinical predictors of neuropsychological performance.

METHODS

The neuropsychological functioning of 32 patients (median age at diagnosis 10.0 years) was prospectively assessed annually for up to 6 years after surgery (median days from surgery at baseline = 72). Tumor location was predominately supratentorial (65.6%). A combination of performance-based and parent-reported measures was used to assess intelligence, memory, executive functioning, and fine motor control in all patients.

RESULTS

Binomial tests at the postoperative baseline revealed that the proportion of children falling below the average range (< 16th percentile) was significantly higher than the rate expected among healthy peers on measures of verbal memory, processing speed, executive functioning, and fine motor control (p < 0.05). Even so, linear mixed models indicated that neuropsychological functioning at the postoperative baseline did not significantly change over time for up to 6 years after surgery across all domains. A larger tumor size was associated with a slower reaction time (p < 0.01). A supratentorial tumor location and history of seizures were associated with more parent-reported executive difficulties (p < 0.01).

CONCLUSIONS

While radiotherapy is a known risk factor for neuropsychological deficits in pediatric brain tumor patients, findings in this study indicate that children treated for low-grade glioma with surgery alone (without radiotherapy or chemotherapy) remain susceptible to difficulties with memory, executive functioning, and motor functioning that persist over time. Over half of the children in the study sample required school support services to address neuropsychological weaknesses. Although low-grade glioma is often conceptualized as a benign tumor, children treated for this lesion require ongoing monitoring and intervention to address neuropsychological weaknesses resulting from the tumor itself as well as the surgery.

Superior Intellectual Outcomes After Proton Radiotherapy Compared With Photon Radiotherapy for Pediatric Medulloblastoma

PURPOSE

Proton radiotherapy (PRT) may lessen the neuropsychological risk traditionally associated with cranial radiotherapy for the treatment of pediatric brain tumors by reducing the dose to normal tissue compared with that of photon radiotherapy (XRT). We examined the change in intellectual scores over time in patients with pediatric medulloblastoma treated with craniospinal PRT versus XRT.

METHODS

Intelligence test scores were obtained for a sample of pediatric patients treated between 2007 and 2018 on the same medulloblastoma protocols that differed only in radiotherapy modality (PRT v XRT). Growth curve analyses compared change in scores over time since diagnosis between groups.

RESULTS

Longitudinal intelligence data from 79 patients (37 PRT, 42 XRT) were examined. Groups were similar on most demographic/clinical variables, including sex (67.1% male), age at diagnosis (mean, 8.6 years), craniospinal irradiation dose (median, 23.4 Gy), length of follow-up (mean, 4.3 years), and parental education (mean, 14.3 years). Boost dose (P < .001) and boost margin (P = .001) differed between groups. Adjusting for covariates, the PRT group exhibited superior long-term outcomes in global intelligence quotient (IQ), perceptual reasoning, and working memory compared with the XRT group (all P < .05). The XRT group exhibited a significant decline in global IQ, working memory, and processing speed (all P < .05). The PRT group exhibited stable scores over time in all domains with the exception of processing speed (P = .003).

CONCLUSION

To our knowledge, this is the first study to compare intellectual trajectories between pediatric patients treated for medulloblastoma with PRT versus those treated with XRT on comparable, contemporary protocols. PRT was associated with more favorable intellectual outcomes in most domains compared with XRT, although processing speed emerged as a vulnerable domain for both groups. This study provides the strongest evidence to date of an intellectual sparing advantage with PRT in the treatment of pediatric medulloblastoma.

Patterns of failure and toxicity profile following proton beam therapy for pediatric bladder and prostate rhabdomyosarcoma

PURPOSE/OBJECTIVE(S)

Bladder and prostate are unfavorable sites for rhabdomyosarcoma (B/P-RMS), and represent a challenging location for radiotherapy.

MATERIALS/METHODS

Nineteen patients with B/P-RMS were enrolled on a prospective registry protocol (2008-2017) and treated with chemotherapy, proton beam therapy (PBT), and surgical resection (n = 8; 42%). Emphasis was given to treatment technique, disease-related outcomes, and toxicity associated with PBT.

RESULTS

The majority of patients had bladder RMS (74%) of embryonal histology (95%), Group III (68%), and intermediate-risk disease by Children's Oncology Group (COG) risk stratification (89%). Seven patients (37%) had primary tumors >5 cm in size. All patients were treated according to COG protocols. With a median follow-up of 66.2 months, 5-year overall survival (OS) and progression-free survival (PFS) were 76%. Four patients (21%) experienced disease relapse, all presenting with local failure. The 5-year local control (LC) rate was 76%. Tumor size predicted LC, with 5-year LC for patients with >5 cm tumors being 43% versus 100% for those with ≤5 cm tumors (P = .006). Univariate analysis demonstrated an effect of tumor size on OS (tumor >5 cm, hazard ratio [HR] 17.7, P = .049) and PFS (HR 17.7, P = .049). Acute grade 2 toxicity was observed in two patients (11%, transient proctitis). Late grade 2+ toxicity was observed in three patients (16%; n = 1 grade 2 skeletal deformity; n = 3 transient grade 2 urinary incontinence; one patient experienced both).

CONCLUSIONS

PBT for B/P-RMS affords promising disease-related outcomes with an acceptable toxicity profile. Higher local failure rates were observed for larger tumors, supporting dose-escalation components of ongoing RMS clinical trials.

Adaptive functioning in pediatric brain tumor survivors: An examination of ethnicity and socioeconomic status

BACKGROUND

Survivors of pediatric brain tumor are at risk for adaptive difficulties. The present study examined adaptive functioning in a multiethnic sample of survivors accounting for socioeconomic status, and whether demographic, diagnostic, and/or treatment-related variables predict adaptive outcomes.

METHOD

Participants included a multiethnic sample of survivors (58 Caucasian, 34 Hispanic, and 22 other non-Caucasian; M age = 14.05 years, SD = 4.33) who were approximately seven years post-treatment. Parents rated adaptive functioning and provided demographic information. Diagnostic and treatment-related information was abstracted from the electronic medical record.

RESULTS

Parent ratings of adaptive functioning were similar across Caucasian, Hispanic, and other non-Caucasian survivors covarying for family income and primary caregiver education, both of which served as proxies for socioeconomic status. All ethnic groups were rated lower than the normative mean in overall adaptive functioning as well as the specific domains of conceptual, social, and practical skills. Demographic, diagnostic, and treatment-related variables were differentially associated with adaptive functioning in survivors of pediatric brain tumor, though socioeconomic status emerged as a strong significant predictor of adaptive functioning domains.

CONCLUSIONS

Adaptive outcomes do not differ as a function of ethnicity after accounting for primary caregiver education and family income. Racial and ethnic minorities may be at increased risk for poorer outcomes given their overrepresentation at lower income levels. Assessing demographic and treatment-related variables early on may be helpful in identifying children likely to develop adaptive difficulties.

Interactions between visual working memory and visual attention among survivors of pediatric acute lymphoblastic leukemia (ALL) and their healthy peers

Introduction: There is increasing concern for adverse cognitive late effects among survivors of pediatric acute lymphoblastic leukemia (ALL) given the widespread impact they have on academic achievement, particularly working memory and attention. We assessed performance among survivors and their healthy peers on a dual task paradigm measuring visual working memory (VWM) and visual attention independently and the dynamic relationship between the two. Assessing specific subsets within cognitive domains allows for understanding the distinct nature of cognitive impairments. Method: Participants were 34 survivors of ALL who have been off-treatment and disease free for 7.5 years; and 20 healthy controls, all between the ages of 10 and 18 years. We utilized behavioral single- and dual-task paradigms. In the dual tasks, participants maintained several items in VWM while performing a visual attention task (Eriksen Flanker Task) that required processing of a target stimulus while inhibiting the processing of distractor stimuli. The single tasks involved performing only the VWM task or only the visual attention task. Results: Results revealed survivors of ALL performed significantly worse than their healthy peers on the single visual attention task but not the single VWM task. Of particular interest, group differences were obtained on the dual VWM and visual attention tasks, such that the VWM and attention tasks reciprocally interfered with each other only among survivors and not their healthy peers. Conclusions: Our results highlight a core deficit in visual attention that is exacerbated by VWM demands among survivors of ALL. The implementation of tasks from cognitive neuroscience paradigms may be sensitive to cognitive impairments experienced by cancer survivors. Assessment and intervention practices among survivors of pediatric ALL are discussed.

Patterns of failure following proton beam therapy for head and neck rhabdomyosarcoma

PURPOSE

Pediatric patients with rhabdomyosarcoma (RMS) of the head and neck (H&N) are treated with multimodal therapy, often with radiotherapy (RT) as definitive local therapy. We report on the patterns of failure following proton beam therapy (PBT) for H&N RMS.

METHODS

Forty-six H&N RMS patients were enrolled on a prospective registry protocol between 2006 and 2015. All were treated with a combination of chemotherapy (ChT) and PBT. Most patients (25 patients, 54%) had parameningeal tumors, of which 11 (24%) had intracranial extension (ICE). Thirteen patients (28%) had primary tumors greater than 5 cm. Median total cyclophosphamide (CPM) equivalent dose was 13.2 g/m² (range 0-16.8 g/m²). Median RT dose was 50.4 Gy(RBE) (range 36 Gy[RBE]-50.8 Gy[RBE]).

RESULTS

With median follow-up of 3.9 years, five-year overall survival was 76%, and five-year progression-free survival was 57%. Seventeen patients (37%) experienced relapse, including 7 with local failure (LF). Five-year local control (LC) was 84%. Tumor size greater than 5 cm predicted increased risk of LF (hazard ratio [HR] 6.49, p = 0.03), as did the presence of ICE at diagnosis (HR 5.21, p = 0.03). Six relapses occurred in patients with ICE; all included a component of central nervous system relapse, with leptomeningeal disease and/or LF with an intracranial component. Delayed RT delivery after week 4 of ChT predicted increased risk of relapse for ICE patients (HR 10.49, p = 0.006).

CONCLUSIONS

PBT confers excellent LC, and a favorable late toxicity profile as compared with prior photon RT data. Our observations support ongoing trial efforts to dose-escalate RT for patients with larger tumors. However, these data raise concerns regarding excess failures among patients with ICE.

Pilot study of DNA methylation-derived neutrophil-to-lymphocyte ratio and survival in pediatric medulloblastoma

INTRODUCTION

Methylation-derived neutrophil-to-lymphocyte ratio (mdNLR) has been identified as a potential prognostic biomarker of outcomes in various cancers. We evaluated the prognostic value of blood-derived mdNLR within a retrospective cohort of pediatric medulloblastoma patients.

MATERIALS AND METHODS

DNA methylation was measured in archival peripheral blood samples collected on 56 pediatric medulloblastoma patients. Hazard ratios (HR) and 95% confidence intervals (CI) for the association between mdNLR and survival were evaluated using Cox proportional hazard models.

RESULTS

Compared to patients who were alive at last follow-up (n = 43), the mean mdNLR value was slightly higher in deceased patients (n = 13) (12.3 vs. 5.2,P =  0.163). Elevated log-transformed mdNLR was suggestively associated with an increased likelihood of death in unadjusted models (HR=1.43, 95%CI: 0.92-2.22) and significantly associated with mortality in adjusted models (HR=1.61, 95%CI: 1.01-2.58).

DISCUSSION

Future work is warranted to investigate the relationship between mdNLR outcomes in specific pediatric medulloblastoma molecular subgroups.

DNA methylation and obesity in survivors of pediatric acute lymphoblastic leukemia: A report from the Childhood Cancer Survivor Study

Because survivors of pediatric acute lymphoblastic leukemia (ALL) are more likely to be obese than unaffected contemporaries, we compared DNA methylation profiles between normal-weight and obese survivors at adiposity-associated CpG sites previously-reported by epigenome-wide association studies (EWAS) of body mass index (BMI) in the general population. We selected 96 ALL survivors from the Childhood Cancer Survivor Study: 48 obese and 48 normal weight. The Illumina HumanMethylation450 BeadChip was used to compare DNA methylation at 211 loci identified in EWAS of BMI in the general population. Thirty-nine loci were associated (false discovery rate <0.05) with obesity among survivors who only received chemotherapy (n = 49). No loci were significantly associated with obesity among CRT-exposed survivors (n = 47). Our results suggest that previously identified BMI-DNA methylation loci are associated with obesity in ALL survivors who were spared CRT, while no loci were significantly associated with obesity in survivors who received CRT.