Growth hormone replacement therapy in children with medulloblastoma: use and effect on tumor control

Evolution of neurosurgical advances and nuances in medulloblastoma therapy

Medulloblastoma, the most common malignant brain tumor in children, presents a complex treatment challenge due to its propensity for infiltrative growth within the posterior fossa and its potential attachment to critical anatomical structures. Central to the management of medulloblastoma is the surgical resection of the tumor, which is a key determinant of patient prognosis. However, the extent of surgical resection (EOR), ranging from gross total resection (GTR) to subtotal resection (STR) or even biopsy, has been the subject of extensive debate and investigation within the medical community. Today, the impact of neurosurgical EOR on the prognosis of medulloblastoma patients remains a complex and evolving area of investigation. The conflicting findings in the literature, the challenges posed by critical surrounding anatomical structures, the potential for surgical complications and neurologic morbidity, and the nuanced interactions with molecular subgroups all contribute to the complexity of this issue. As the field continues to advance, the imperative to strike a delicate balance between maximizing resection and preserving quality of life remains central to the management of medulloblastoma patients.

Growth hormone after CNS tumor diagnosis: the fundamentals, fears, facts, and future directions

Growth hormone deficiency (GHD) may occur in pediatric patients with central nervous system (CNS) tumors at initial tumor presentation or later as treatment-related sequelae. While it is well recognized that growth hormone (GH) has beneficial effects on growth and endocrinopathies, there's often hesitancy by clinicians to initiate GH therapy for GHD after CNS tumor diagnosis due to the perceived increased risk of tumor recurrence. The available data is described here and based on this review, there is no evidence of increased risk of tumor recurrence or secondary malignancy in patients treated with GH after CNS tumor diagnosis. Further understanding of tumor biology and presence of downstream GH targets including insulin-like growth factor-1 (IGF-1) and insulin receptor activity is still needed.

Influence of growth hormone therapy on germinoma survivors

PURPOSE

Due to the effectiveness of growth hormone therapy (GHT), the number of cancer survivors receiving GHT has increased. Previous studies had indicated that GHT was not associated with the increasing risks of tumor recurrence and development with second neoplasm (SN) in cancer survivors. However, to date, research on those risks in germinoma survivors is still limited. The aim of this study is to evaluate the impact of GHT in relation to tumor recurrence and development with SN in pure germinoma survivors.

METHODS

This retrospective cohort study was approved by the Ethical Committee for Epidemiology of our institution. Seventy-three consecutive patients who underwent a biopsy of the lesion and were diagnosed with pure germinoma were retrospectively studied. They (median age, 15.0 years) were followed up more than 1 year after biopsy (median follow-up period, 14.3 years). The following data was obtained from the medical records of the patients: age, sex, preoperative magnetic resonance imaging findings, hormonal replacement, and events including tumor recurrence and/or SN.

RESULTS

In our patient series, 16 patients (21.9%) who were more likely to have neurohypophysial lesion and receive multiple hormonal therapies had received GHT. No significant differences in the rates of tumor recurrence and development with SN were observed between the patients who had and had not received GHT. Moreover, the recurrence-free survival and overall survival rates were not different between the patients who had and had not received GHT.

CONCLUSIONS

GHT did not increase the risks of tumor recurrence and development with SN in pure germinoma survivors.

Hypothalamic-Pituitary and Other Endocrine Surveillance Among Childhood Cancer Survivors

Endocrine disorders in survivors of childhood, adolescent, and young adult (CAYA) cancers are associated with substantial adverse physical and psychosocial effects. To improve appropriate and timely endocrine screening and referral to a specialist, the International Late Effects of Childhood Cancer Guideline Harmonization Group (IGHG) aims to develop evidence and expert consensus-based guidelines for healthcare providers that harmonize recommendations for surveillance of endocrine disorders in CAYA cancer survivors. Existing IGHG surveillance recommendations for premature ovarian insufficiency, gonadotoxicity in males, fertility preservation, and thyroid cancer are summarized. For hypothalamic-pituitary (HP) dysfunction, new surveillance recommendations were formulated by a guideline panel consisting of 42 interdisciplinary international experts. A systematic literature search was performed in MEDLINE (through PubMed) for clinically relevant questions concerning HP dysfunction. Literature was screened for eligibility. Recommendations were formulated by drawing conclusions from quality assessment of all evidence, considering the potential benefits of early detection and appropriate management. Healthcare providers should be aware that CAYA cancer survivors have an increased risk for endocrine disorders, including HP dysfunction. Regular surveillance with clinical history, anthropomorphic measures, physical examination, and laboratory measurements is recommended in at-risk survivors. When endocrine disorders are suspected, healthcare providers should proceed with timely referrals to specialized services. These international evidence-based recommendations for surveillance of endocrine disorders in CAYA cancer survivors inform healthcare providers and highlight the need for long-term endocrine follow-up care in subgroups of survivors and elucidate opportunities for further research.

The Current State of Radiotherapy for Pediatric Brain Tumors: An Overview of Post-Radiotherapy Neurocognitive Decline and Outcomes

Tumors of the central nervous system are the most common solid malignancies diagnosed in children. While common, they are also found to have some of the lowest survival rates of all malignancies. Treatment of childhood brain tumors often consists of operative gross total resection with adjuvant chemotherapy or radiotherapy. The current body of literature is largely inconclusive regarding the overall benefit of adjuvant chemo- or radiotherapy. However, it is known that both are associated with conditions that lower the quality of life in children who undergo those treatments. Chemotherapy is often associated with nausea, emesis, significant fatigue, immunosuppression, and alopecia. While radiotherapy can be effective for achieving local control, it is associated with late effects such as endocrine dysfunction, secondary malignancy, and neurocognitive decline. Advancements in radiotherapy grant both an increase in lifetime survival and an increased lifetime for survivors to contend with these late effects. In this review, the authors examined all the published literature, analyzing the results of clinical trials, case series, and technical notes on patients undergoing radiotherapy for the treatment of tumors of the central nervous system with a focus on neurocognitive decline and survival outcomes.

Safety of growth hormone replacement in survivors of cancer and intracranial and pituitary tumours: a consensus statement

Growth hormone (GH) has been used for over 35 years, and its safety and efficacy has been studied extensively. Experimental studies showing the permissive role of GH/insulin-like growth factor 1 (IGF-I) in carcinogenesis have raised concerns regarding the safety of GH replacement in children and adults who have received treatment for cancer and those with intracranial and pituitary tumours. A consensus statement was produced to guide decision-making on GH replacement in children and adult survivors of cancer, in those treated for intracranial and pituitary tumours and in patients with increased cancer risk. With the support of the European Society of Endocrinology, the Growth Hormone Research Society convened a Workshop, where 55 international key opinion leaders representing 10 professional societies were invited to participate. This consensus statement utilized: (1) a critical review paper produced before the Workshop, (2) five plenary talks, (3) evidence-based comments from four breakout groups, and (4) discussions during report-back sessions. Current evidence reviewed from the proceedings from the Workshop does not support an association between GH replacement and primary tumour or cancer recurrence. The effect of GH replacement on secondary neoplasia risk is minor compared to host- and tumour treatment-related factors. There is no evidence for an association between GH replacement and increased mortality from cancer amongst GH-deficient childhood cancer survivors. Patients with pituitary tumour or craniopharyngioma remnants receiving GH replacement do not need to be treated or monitored differently than those not receiving GH. GH replacement might be considered in GH-deficient adult cancer survivors in remission after careful individual risk/benefit analysis. In children with cancer predisposition syndromes, GH treatment is generally contraindicated but may be considered cautiously in select patients.

A 40-Year Cohort Study of Evolving Hypothalamic Dysfunction in Infants and Young Children (<3 years) with Optic Pathway Gliomas

Simple Summary

Serious, poorly understood health issues affect young children with optic pathway tumours. We studied the risk of developing life-limiting hormonal, metabolic, and neurobehavioural disorders by tumour position, recurrence, and treatment, in those diagnosed under 3 years. We found the highest risk for future complex health issues in those presenting with failure to thrive, under one year of age, and/or a tumour involving a deep midbrain area called the hypothalamus. Time, repeated tumour growth, and salvage therapies (radiotherapy, surgery) contributed. We highlight the need for a better understanding of tumour-induced midbrain injury and for neurobehavioural and hormonal support to inform rehabilitation in the growing years, during and beyond cure, to optimise quality of life for these survivors and their families. This might inform oncology treatment strategies and determine new areas for support and collaborative neuroscience research in this high survival group.

Abstract

Despite high survival, paediatric optic pathway hypothalamic gliomas are associated with significant morbidity and late mortality. Those youngest at presentation have the worst outcomes. We aimed to assess presenting disease, tumour location, and treatment factors implicated in the evolution of neuroendocrine, metabolic, and neurobehavioural morbidity in 90 infants/children diagnosed before their third birthday and followed-up for 9.5 years (range 0.5–25.0). A total of 52 (57.8%) patients experienced endo-metabolic dysfunction (EMD), the large majority (46) of whom had hypothalamic involvement (H+) and lower endocrine event-free survival (EEFS) rates. EMD was greatly increased by a diencephalic syndrome presentation (85.2% vs. 46%, p = 0.001)), H+ (OR 6.1 95% CI 1.7–21.7, p 0.005), radiotherapy (OR 16.2, 95% CI 1.7–158.6, p = 0.017) and surgery (OR 4.8 95% CI 1.3–17.2, p = 0.015), all associated with anterior pituitary disorders. Obesity occurred in 25% of cases and was clustered with the endocrinopathies. Neurobehavioural deficits occurred in over half (52) of the cohort and were associated with H+ (OR 2.5 95% C.I. 1.1–5.9, p = 0.043) and radiotherapy (OR 23.1 C.I. 2.9–182, p = 0.003). Very young children with OPHG carry a high risk of endo-metabolic and neurobehavioural comorbidities which deserve better understanding and timely/parallel support from diagnosis to improve outcomes. These evolve in complex, hierarchical patterns over time whose aetiology appears predominantly determined by injury from the hypothalamic tumour location alongside adjuvant treatment strategies.

Children's Oncology Group Phase III Trial of Reduced-Dose and Reduced-Volume Radiotherapy With Chemotherapy for Newly Diagnosed Average-Risk Medulloblastoma

PURPOSE

Children with average-risk medulloblastoma (MB) experience survival rates of ≥ 80% at the expense of adverse consequences of treatment. Efforts to mitigate these effects include deintensification of craniospinal irradiation (CSI) dose and volume.

METHODS

ACNS0331 (ClinicalTrials.gov identifier: NCT00085735) randomly assigned patients age 3-21 years with average-risk MB to receive posterior fossa radiation therapy (PFRT) or involved field radiation therapy (IFRT) following CSI. Young children (3-7 years) were also randomly assigned to receive standard-dose CSI (SDCSI; 23.4 Gy) or low-dose CSI (LDCSI; 18 Gy). Post hoc molecular classification and mutational analysis contextualized outcomes according to known biologic subgroups (Wingless, Sonic Hedgehog, group 3, and group 4) and genetic biomarkers. Neurocognitive changes and ototoxicity were monitored over time.

RESULTS

Five hundred forty-nine patients were enrolled on study, of which 464 were eligible and evaluable to compare PFRT versus IFRT and 226 for SDCSI versus LDCSI. The five-year event-free survival (EFS) was 82.5% (95% CI, 77.2 to 87.8) and 80.5% (95% CI, 75.2 to 85.8) for the IFRT and PFRT regimens, respectively, and 71.4% (95% CI, 62.8 to 80) and 82.9% (95% CI, 75.6 to 90.2) for the LDCSI and SDCSI regimens, respectively. IFRT was not inferior to PFRT (hazard ratio, 0.97; 94% upper CI, 1.32). LDCSI was inferior to SDCSI (hazard ratio, 1.67%; 80% upper CI, 2.10). Improved EFS was observed in patients with Sonic Hedgehog MB who were randomly assigned to the IFRT arm (P = .018). Patients with group 4 MB receiving LDCSI exhibited inferior EFS (P = .047). Children receiving SDCSI exhibited greater late declines in IQ (estimate = 5.87; P = .021).

CONCLUSION

Reducing the radiation boost volume in average-risk MB is safe and does not compromise survival. Reducing CSI dose in young children with average-risk MB results in inferior outcomes, possibly in a subgroup-dependent manner, but is associated with better neurocognitive outcome. Molecularly informed patient selection warrants further exploration for children with MB to be considered for late-effect sparing approaches.

Diagnosis and Treatment of Growth Hormone Deficiency: A Position Statement from Korean Endocrine Society and Korean Society of Pediatric Endocrinology

Growth hormone (GH) deficiency is caused by congenital or acquired causes and occurs in childhood or adulthood. GH replacement therapy brings benefits to body composition, exercise capacity, skeletal health, cardiovascular outcomes, and quality of life. Before initiating GH replacement, GH deficiency should be confirmed through proper stimulation tests, and in cases with proven genetic causes or structural lesions, repeated GH stimulation testing is not necessary. The dosing regimen of GH replacement therapy should be individualized, with the goal of minimizing side effects and maximizing clinical improvements. The Korean Endocrine Society and the Korean Society of Pediatric Endocrinology have developed a position statement on the diagnosis and treatment of GH deficiency. This position statement is based on a systematic review of evidence and expert opinions.

Adult growth hormone deficiency: clinical advances and approaches to improve adherence

Introduction: There have been significant clinical advances in the understanding of the diagnosis and benefits of long-term recombinant human growth hormone (rhGH) replacement in adults with GH deficiency (GHD) since its approval in 1996 by the United States Food and Drug Administration.Areas covered: We searched PubMed, Medline, CINAHL, EMBASE and PsychInfo databases between January 2000 and June 2019 for published studies evaluating adults with GHD. We reviewed the data of the oral macimorelin test compared to the GHRH plus arginine and the insulin tolerance tests that led to its approval by the United States FDA and European Medicines Agency for adult diagnostic testing. We summarize the clinical advances of long-term benefits of rhGH therapy and the potential effects of GH receptor polymorphisms on individual treatment responsiveness. We identify that non-adherence and discontinuation rates are high and recommend strategies to support patients to improve adherence. We also provide an overview of several long-acting GH (LAGH) preparations currently under development and their potential role in improving treatment adherence.Expert opinion: This article summarizes recent clinical advances in rhGH replacement therapy, the biological and molecular aspects that may influence rhGH action, and offers practical strategies to enhance adherence in adults with GHD.

Safety Outcomes During Pediatric GH Therapy: Final Results From the Prospective GeNeSIS Observational Program

Context

Safety concerns have been raised regarding premature mortality, diabetes, neoplasia, and cerebrovascular disease in association with GH therapy.

Objective

To assess incidence of key safety outcomes.

Design

Prospective, multinational, observational study (1999 to 2015).

Setting

A total of 22,311 GH-treated children from 827 investigative sites in 30 countries.

Patients

Children with growth disorders.

Interventions

GH treatment.

Main outcome measures

Standardized mortality ratio (SMR) and standardized incidence ratio (SIR) with 95% CIs for mortality, diabetes, and primary cancer using general population registries.

Results

Predominant short stature diagnoses were GH deficiency (63%), idiopathic short stature (13%), and Turner syndrome (8%), with mean ± SD follow-up of 4.2 ± 3.2 years (∼92,000 person-years [PY]). Forty-two deaths occurred in patients with follow-up, with an SMR (95% CI) of 0.61 (0.44, 0.82); the SMR was elevated for patients with cancer-related organic GH deficiency [5.87 (3.21, 9.85)]. Based on 18 cases, type 2 diabetes mellitus (T2DM) risk was elevated [SIR: 3.77 (2.24, 5.96)], but 72% had risk factors. In patients without cancer history, 14 primary cancers were observed [SIR: 0.71 (0.39, 1.20)]. Second neoplasms occurred in 31 of 622 cancer survivors [5.0%; 10.7 (7.5, 15.2) cases/1000 PY] and intracranial tumor recurrences in 67 of 823 tumor survivors [8.1%; 16.9 (13.3, 21.5) cases/1000 PY]. All three hemorrhagic stroke cases had risk factors.

Conclusions

GeNeSIS (Genetics and Neuroendocrinology of Short Stature International Study) data support the favorable safety profile of pediatric GH treatment. Overall risk of death or primary cancer was not elevated in GH-treated children, and no hemorrhagic strokes occurred in patients without risk factors. T2DM incidence was elevated compared with the general population, but most cases had diabetes risk factors.

Is there an increased risk of spinal relapse in standard-risk medulloblastoma/primitive neuroectodermal tumor patients who receive only a reduced dose of craniospinal radiotherapy?

PURPOSE

Medulloblastoma (MBL) is the most common pediatric brain malignancy. Postoperative radiotherapy to the entire craniospinal axis is the standard-of-care but has linked to long-term morbidity. In this study, we analyzed the implication of reduced dose craniospinal radiotherapy (RT) for survival and pattern of relapse in MBL patients.

MATERIAL AND METHODS

The clinical characteristics of 32 consecutively diagnosed medulloblastoma/primitive neuroectodermal tumor patients were analyzed. After surgical resection, a dose of 23.4 Gy of spinal RT with a posterior fossa boost of 30.6 Gy was prescribed to standard-risk patients, whereas high-risk patients received 36 Gy spinal RT with additional boosts to the posterior fossa up to 54 Gy. Then, both groups received the same chemotherapy protocol.

RESULTS

Five-year OS for standard and high-risk patients was 94 and 50%, respectively. When analyzing prognostic factors, postoperative tumor size is the most important one which affects the OS. Ten patients relapsed during follow-up, and there was no isolated spinal relapse in either group.

CONCLUSION

The risk of isolated spinal relapse does not increase with reduced-dose craniospinal RT, since there is no isolated relapse in either the standard or high-risk groups of patients.

GH Therapy in Childhood Cancer Survivors: A Systematic Review and Meta-Analysis

BACKGROUND

GH deficiency (GHD) is common among childhood cancer survivors (CCSs) with history of tumors, surgery, and/or radiotherapy involving the hypothalamus-pituitary region. We aimed to evaluate the effects of GH therapy (GHT) in CCSs on adult height, risk of diabetes mellitus, abnormal lipids, metabolic syndrome, quality of life, secondary tumors, and disease recurrence.

METHODS

We searched multiple databases for randomized and observational studies. Pairs of reviewers independently selected studies and collected data. Random effects meta-analysis was used to pool outcomes across the studies.

RESULTS

We included 29 observational studies at moderate to high risk of bias. Sixteen studies compared CCSs on GHT with those not on GHT (512 patients, GH dose: 0.3 to 0.9 IU/kg/week). GHT was significantly associated with height gain [standard deviation score, 0.61; 95% CI, 0.08 to 1.13] and was not significantly associated with the occurrence of secondary tumors [odds ratio (OR), 1.10; 95% CI, 0.72 to 1.67] or tumor recurrence (OR, 0.57; 95% CI, 0.31 to 1.02). Thirteen studies compared CCSs on GHT with normal age- or sex-matched controls or controls with idiopathic GHD or short stature. GHT was associated with either improved or unchanged risk of diabetes, lipid profiles, and metabolic syndrome. GHT was associated with improvements in quality of life.

CONCLUSION

CCSs treated with GHT gain height compared with the untreated controls. GHT may improve lipid profiles and quality of life and does not appear to increase the risk of diabetes or the development of secondary tumors, although close monitoring for such complications remains warranted due to uncertainty in the current evidence.

Spinal Growth Patterns After Craniospinal Irradiation in Children With Medulloblastoma

PURPOSE

This study aimed to evaluate the impact on spine growth in children with medulloblastoma using either photon or electron craniospinal irradiation (CSI).

METHODS AND MATERIALS

This was a single institution retrospective review of children who were treated with CSI for medulloblastoma. Spine growth was measured on magnetic resonance imaging scans at defined locations on the basis of a published predictive model of spine growth after CSI. Differences between spine growth in the anterior, middle, and posterior aspect of the designated vertebral segments were also assessed. Differences between the groups treated with photons or electrons were assessed with student's t test.

RESULTS

A total of 19 patients (10 patients treated with electrons and 9 with photons) with a median follow-up time of 45.5 months (confidence interval, 34.9-55.1 months) were evaluated. Patients treated with electrons were younger than those who received photons (5.1 years [range, 3.8-9.0 years] vs 9.6 years [range, 3.5-12.9 years]); however, there were no differences in other clinical characteristics, treatment, or follow-up between the groups. Spine growth rate for patients treated with electrons fit the predictive model (104% ± 5.2%), but patients treated with photons had growth that was faster than predicted by the model (150% ± 47%) and different from that observed with electrons. The differences between treatment the modalities were statistically significant (P = .03). For patients treated with photons, there were no statistical differences between the growth rate of the anterior vertebral body compared with the posterior aspect, but for patients treated with electrons, a faster spine growth in the anterior L1-L5 lumbar spine was observed compared with the posterior lumbar spine (3.90 vs 2.52 mm/year; P = .006) without differences in the cervical or thoracic spine.

CONCLUSIONS

The use of electrons to treat the craniospinal axis in children with medulloblastoma resulted in no significant difference in spine growth compared with the predicted spine growth on the basis of previously published models using photons, but with a clinically insignificant faster spine growth rate in the anterior lumbar spine.

Growth hormone treatment of Canadian children: results from the GeNeSIS phase IV prospective observational study

BACKGROUND

Country-specific data on outcomes of treatment with recombinant human growth hormone are lacking. We present such data for children treated with growth hormone in Canada.

METHODS

We describe characteristics and outcomes of 850 children (mean age at baseline 8.5 yr) treated with growth hormone constituting the Canadian cohort of the multinational phase IV prospective observational Genetics and Neuroendocrinology of Short-stature International Study (GeNeSIS). The diagnosis associated with short stature was as determined by the investigator. Auxological data were evaluated yearly until near-adult height. Adverse events were assessed in all growth-hormone-treated patients.

RESULTS

The diagnosis ascribed as the cause of short stature was growth hormone deficiency in 526 children (61.9%), predominantly organic rather than idiopathic, particularly congenital pituitary abnormalities and intracranial tumours. All diagnostic groups with sufficient patients for analysis had increased height velocity standard deviation score (SDS) and height SDS during growth hormone treatment. For patients who reached near-adult height (n = 293), the mean height SDS was within the normal range for about 80% of patients with organic growth hormone deficiency (n = 131) or idiopathic growth hormone deficiency (n = 50), 50% of patients with idiopathic short stature (n = 10) and 46% of patients with Turner syndrome (n = 79). Eleven deaths were reported, 7 in patients with organic growth hormone deficiency. Serious adverse events considered related to growth hormone treatment (n = 19) were isolated except for medulloblastoma recurrence (n = 2) and adenoidal hypertrophy (n = 2).

INTERPRETATION

Growth hormone treatment was effective and had a good safety profile in Canadian children. Growth hormone dosages were lower than in the US and global GeNeSIS cohorts, and a greater proportion of treated Canadian children had organic growth hormone deficiency.

STUDY REGISTRATION

ClinicalTrials.gov, no. NCT01088412.

Mortality in Children Receiving Growth Hormone Treatment of Growth Disorders: Data From the Genetics and Neuroendocrinology of Short Stature International Study

CONTEXT

Although pediatric growth hormone (GH) treatment is generally considered safe for approved indications, concerns have been raised regarding potential for increased risk of mortality in adults treated with GH during childhood.

OBJECTIVE

To assess mortality in children receiving GH.

DESIGN

Prospective, multinational, observational study.

SETTING

Eight hundred twenty-seven study sites in 30 countries.

PATIENTS

Children with growth disorders.

INTERVENTIONS

GH treatment during childhood.

MAIN OUTCOME MEASURE

Standardized mortality ratios (SMRs) and 95% confidence intervals (CIs) using age- and sex-specific rates from the general population.

RESULTS

Among 9504 GH-treated patients followed for ≥4 years (67,163 person-years of follow-up), 42 deaths were reported (SMR, 0.77; 95% CI, 0.56 to 1.05). SMR was significantly elevated in patients with history of malignant neoplasia (6.97; 95% CI, 3.81 to 11.69) and borderline elevated for those with other serious non-GH-deficient conditions (2.47; 95% CI, 0.99-5.09). SMRs were not elevated for children with history of benign neoplasia (1.44; 95% CI, 0.17 to 5.20), idiopathic GHD (0.11; 95% CI, 0.02 to 0.33), idiopathic short stature (0.20; 95% CI, 0.01 to 1.10), short stature associated with small for gestational age (SGA) birth (0.66; 95% CI, 0.08 to 2.37), Turner syndrome (0.51; 95% CI, 0.06 to 1.83), or short stature homeobox-containing (SHOX) gene deficiency (0.83; 95% CI, 0.02 to 4.65).

CONCLUSIONS

No significant increases in mortality were observed for GH-treated children with idiopathic GHD, idiopathic short stature, born SGA, Turner syndrome, SHOX deficiency, or history of benign neoplasia. Mortality was elevated for children with prior malignancy and those with underlying serious non-GH-deficient medical conditions.

Case-based review: pediatric medulloblastoma

Medulloblastoma is the most common malignant brain tumor affecting children. These tumors are high grade with propensity to metastasize within the central nervous system and, less frequently, outside the neuraxis. Recent advancements in molecular subgrouping of medulloblastoma refine diagnosis and improve counseling in regards to overall prognosis. Both are predicated on the molecular drivers of each subgroup-WNT-activated, SHH-activated, group 3, and group 4. The traditional therapeutic mainstay for medulloblastoma includes a multimodal approach with surgery, radiation, and multiagent chemotherapy. As we discover more about the molecular basis of medulloblastoma, efforts to adjust treatment approaches based on molecular risk stratification are under active investigation. Certainly, the known neurological, developmental, endocrine, and psychosocial injury related to medulloblastoma and its associated therapies motivate ongoing research towards improving treatment for this life-threatening tumor while at the same time minimizing long-term side effects.

Physiological growth hormone replacement and rate of recurrence of craniopharyngioma: the Genentech National Cooperative Growth Study

OBJECTIVE The object of this study was to establish recurrence rates in patients with craniopharyngioma postoperatively treated with recombinant human growth hormone (rhGH) as a basis for determining the risk of rhGH therapy in the development of recurrent tumor. METHODS The study included 739 pediatric patients with craniopharyngioma who were naïve to GH upon entering the Genentech National Cooperative Growth Study (NCGS) for treatment. Reoperation for tumor recurrence was documented as an adverse event. Cox proportional-hazards regression models were developed for time to recurrence, using age as the outcome and enrollment date as the predictor. Patients without recurrence were treated as censored. Multivariate logistic regression was used to examine the incidence of recurrence with adjustment for the amount of time at risk. RESULTS Fifty recurrences in these 739 surgically treated patients were recorded. The overall craniopharyngioma recurrence rate in the NCGS was 6.8%, with a median follow-up time of 4.3 years (range 0.7-6.4 years.). Age at the time of study enrollment was statistically significant according to both Cox (p = 0.0032) and logistic (p < 0.001) models, with patients under 9 years of age more likely to suffer recurrence (30 patients [11.8%], 0.025 recurrences/yr of observation, p = 0.0097) than those ages 9-13 years (17 patients [6.0%], 0.17 recurrences/yr of observation) and children older than 13 years (3 patients [1.5%], 0.005 recurrences/yr of observation). CONCLUSIONS Physiological doses of GH do not appear to increase the recurrence rate of craniopharyngioma after surgery in children, but long-term follow-up of GH-treated patients is required to establish a true natural history in the GH treatment era.

Considering GH replacement for GH-deficient adults with a previous history of cancer: a conundrum for the clinician

Previous studies have shown that GH and IGF-I may enhance tumorigenesis, metastasis, and cell proliferation in humans and animals. Evidence supporting this notion is derived from animal model studies, epidemiological studies, experience from patients with acromegaly, molecular therapeutic manipulation of GH and IGF-I actions, and individuals with GH receptor and congenital IGF-I deficiencies. Prior exposure to radiation therapy, aging, family history of cancer, and individual susceptibility may also contribute to increase this risk. Therefore, the use of GH replacement in patients with a history of cancer raises hypothetical safety concerns for patients, caregivers, and providers. Studies of GH therapy in GH-deficient adults with hypopituitarism and childhood cancer survivors have not convincingly demonstrated an increased cancer risk. Conversely, the risk of occurrence of a second neoplasm (SN) in childhood cancer survivors may be increased, with meningiomas being the most common tumor; however, this risk appears to decline over time. In light of these findings, if GH replacement is to be considered in patients with a previous history of cancer, we propose this consideration to be based on each individual circumstance and that such therapy should only be initiated at least 2 years after cancer remission is achieved with the understanding that in some patients (particularly those with childhood cancers), GH may potentially increase the risk of SNs. In addition, close surveillance should be undertaken working closely with the patient's oncologist. More long-term data are thus needed to determine if GH replacement in GH-deficient adults with a history of cancer is associated with the development of de novo tumors and tumor recurrence.

Prognostic value of medulloblastoma extent of resection after accounting for molecular subgroup: a retrospective integrated clinical and molecular analysis

Background

Incomplete surgical resection of medulloblastoma is controversially considered a marker of high-risk disease; driving aggressive surgical resections, “second-look” surgeries, and/or intensified chemoradiotherapy. All prior publications evaluating the clinical importance of extent of resection (EOR) failed to account for molecular subgroup. We analysed the prognostic value of EOR across 787 medulloblastoma samples in a subgroup-specific manner.

Methods

We retrospectively identified patients from Medulloblastoma Advanced Genomics International Consortium (MAGIC) centres with a histological diagnosis of medulloblastoma and complete extent of resection and survival data. Specimens were collected from 35 international institutions. Medulloblastoma subgroup affiliation was determined using nanoString gene expression profiling on frozen or formalin-fixed paraffin-embedded tissues. Extent of resection (EOR) based on post-operative imaging was classified as gross total (GTR), near total (NTR, <1·5cm²), or subtotal (STR, ≥ 1·5cm²). Overall survival (OS) and progression-free survival (PFS) multivariable analyses including subgroup, age, metastatic status, geographical location of therapy (North America/Australia vs world), and adjuvant therapy regimen were performed. The primary endpoint was the impact of surgical EOR by molecular subgroup and other clinical variables on OS and PFS.

Findings

787 medulloblastoma patients (86 WNT, 242 SHH, 163 Group 3, and 296 Group 4) were included in a multivariable Cox model of PFS and OS. The marked benefit of EOR in the overall cohort was greatly attenuated after including molecular subgroup in the multivariable analysis. There was an observed PFS benefit of GTR over STR (hazard ration [HR] 1·45, 95% CI; 1·07–1·96, p=0·02) but there was no observed PFS or OS benefit of GTR over NTR (HR 1·05, 0·71–1·53, p=0·82 and HR 1·14, 0·75–1·72, p=0.55). There was no statistically significant survival benefit to greater EOR for patients with WNT, SHH, or Group 3 patients (HR 1·03, 0·67–1·58, p=0·9 for STR vs. GTR). There was a PFS benefit for GTR over STR in patients with Group 4 medulloblastoma (HR1·97, 1·22–3·17, p=0·01), particularly those with metastatic disease (HR 2·22, 1–4·93, p=0·05). A nomogram based on this multivariable cox proportional hazards model shows the comparably smaller impact of EOR on relative risk for PFS and OS than subgroup affiliation, metastatic status, radiation dose, and adjuvant chemotherapy.

Interpretation

The prognostic benefit of EOR for patients with medulloblastoma is attenuated after accounting for molecular subgroup affiliation. Although maximal safe surgical resection should remain the standard of care, surgical removal of small residual portions of medulloblastoma is not recommended when the likelihood of neurological morbidity is high as there is no definitive benefit to GTR over NTR. Our results suggest a re-evaluation of the long-term implications of intensified craniospinal irradiation (36 Gy) in children with small residual portions of medulloblastoma.

Funding

Funding Canadian Cancer Society Research Institute, Terry Fox Research Institute, Canadian Institutes of Health Research, National Institutes of Health, Pediatric Brain Tumor Foundation, Garron Family Chair in Childhood Cancer Research.

Endocrinologic Consequences of Pediatric Posterior Fossa Tumours

Intracranial tumors are the second most frequent malignancies in children and posterior fossa is a common location for these neoplasias during childhood. Recent advances in surgical techniques, radiotherapy and chemotherapy resulted in dramatic increase in the survival rates of these children, however they are still source of a significant morbidity and mortality. Endocrinological complications and late sequelae of childhood posterior fossa tumours are common among the survivors of these tumours and include growth retardation, hypothyroidism, pubertal disorders, gonadal dysfunction and osteopenia. These complications have significant impact on the quality of life of the survivors of childhood posterior fossa tumours. In this paper, the frequency, etiology, and management of these complications will be reviewed.

Factors affecting survival of medulloblastoma in children: the changing concept of management

Medulloblastoma (MB) is a type of malignant tumor arising only in the cerebellum that was first defined by Cushing and Bailey in 1920s. In this review paper, we trace the evolution of risk stratification and the correlated changing concept of management in the past years. Outcome analysis of the hospital series of the Taipei Veterans General Hospital, Cheng Hsin General Hospital, and Taipei Medical University Hospital was performed to correlate prognostic indicators with reported studies. The purpose is to provide clues for age-specific and risk-adjusted optimal, effective, but beneficial and protective treatment strategies of these tumors in children.

Growth hormone therapy and risk of recurrence/progression in intracranial tumors: a meta-analysis

Growth hormone deficiency is common in intracranial tumors, which is usually treated with surgery and radiotherapy. A number of previous studies have investigated the relationship between the growth hormone replacement therapy (GHRT) and risk of tumor recurrence/progression; however, the evidence remains controversial. We conducted a meta-analysis of published studies to estimate the potential relation between GHRT and intracranial tumors recurrence/progression. Three comprehensive databases, PUBMED, EMBASE, and Cochrane Library, were researched with no limitations, covering all published studies till the end of July, 2014. Reference lists from identified studies were also screened for additional database. The summary relative risks (RR) and 95% confidence intervals (CI) were calculated by fixed-effects models for estimation. Fifteen eligible studies, involving more than 2232 cases and 3606 controls, were included in our meta-analysis. The results indicated that intracranial tumors recurrence/progression was not associated with GHRT (RR 0.48, 95% CI 0.39-0.56), and for children, the pooled RR was 0.44 and 95% CI was 0.34-0.54. In subgroup analysis, risks of recurrence/progression were decreased for craniopharyngioma, medulloblastoma, astrocytoma, glioma, but not for pituitary adenomas, and non-functioning pituitary adenoma (NFPA), ependymoma. Results from our analysis indicate that GHRT decreases the risk of recurrence/progression in children with intracranial tumors, craniopharyngioma, medulloblastoma, astrocytoma, or glioma. However, GHRT for pituitary adenomas, NFPA, and ependymoma was not associated with the recurrence/progression of the tumors. GH replacement seems safe from the aspect of risk of tumor progression.

Risk of Neoplasia in Pediatric Patients Receiving Growth Hormone Therapy--A Report From the Pediatric Endocrine Society Drug and Therapeutics Committee

CONTEXT

GH and IGF-1 have been shown to affect tumor growth in vitro and in some animal models. This report summarizes the available evidence on whether GH therapy in childhood is associated with an increased risk of neoplasia during treatment or after treatment is completed.

EVIDENCE ACQUISITION

A PubMed search conducted through February 2014 retrieved original articles written in English addressing GH therapy and neoplasia risk. Subsequent searches were done to include additional relevant publications.

EVIDENCE SYNTHESIS

In children without prior cancer or known risk factors for developing cancer, the clinical evidence does not affirm an association between GH therapy during childhood and neoplasia. GH therapy has not been reported to increase the risk for neoplasia in this population, although most of these data are derived from postmarketing surveillance studies lacking rigorous controls. In patients who are at higher risk for developing cancer, current evidence is insufficient to conclude whether or not GH further increases cancer risk. GH treatment of pediatric cancer survivors does not appear to increase the risk of recurrence but may increase their risk for subsequent primary neoplasms.

CONCLUSIONS

In children without known risk factors for malignancy, GH therapy can be safely administered without concerns about an increased risk for neoplasia. GH use in children with medical diagnoses predisposing them to the development of malignancies should be critically analyzed on an individual basis, and if chosen, appropriate surveillance for malignancies should be undertaken. GH can be used to treat GH-deficient childhood cancer survivors who are in remission with the understanding that GH therapy may increase their risk for second neoplasms.

Growth hormone replacement in patients with a history of malignancy: a review of the literature and best practice for offering treatment

Previous studies have implicated the growth hormone (GH)/IGF-I axis as an important mediator of cancer risk in humans and animals. Evidence supporting this notion is derived from animal studies, epidemiological observations, patients with acromegaly and from therapeutic manipulation of GH and IGF-I actions. Therefore, the use of GH therapy in patients with a history of malignancy raises hypothetical safety concerns. Reassuringly, GH therapy in childhood cancer survivors has not been confirmed to increase the cancer risk. Conversely, the risk of occurrence of a second neoplasm may be increased, with meningiomas being the most common tumor. In light of these findings, we propose considering GH therapy to be based on each individual's circumstance and commenced at least 2 years after cancer remission is achieved with close monitoring during therapy. More long-term data are needed on the safety of GH replacement therapy in GH-deficient adults with a history of malignancy.

Growth hormone treatment and risk of malignancy

Growth hormone (GH) treatment has been increasingly widely used for children with GH deficiencies as the survival rate of pediatric patients with malignancies has increased. Both GH and insulin-like growth factor-I have mitogenic and antiapoptotic activity, prompting concern that GH treatment may be associated with tumor development. In this review, the authors examined the relationship between GH treatment and cancer risk in terms of de novo malignancy, recurrence, and secondary neoplasm. Although the results from numerous studies were not entirely consistent, this review of various clinical and epidemiological studies demonstrated that there is no clear evidence of a causal relationship between GH treatment and tumor development. Nonetheless, a small number of studies reported that childhood cancer survivors who receive GH treatment have a small increased risk of developing de novo cancer and secondary malignant neoplasm. Therefore, regular follow-ups and careful examination for development of cancer should be required in children who receive GH treatment. Continued surveillance for an extended period is essential for monitoring long-term safety.

Growth hormone exposure as a risk factor for the development of subsequent neoplasms of the central nervous system: a report from the childhood cancer survivor study

CONTEXT

Cranial radiation therapy (CRT) predisposes to GH deficiency and subsequent neoplasms (SNs) of the central nervous system (CNS). Increased rates of SNs have been reported in GH-treated survivors.

OBJECTIVE

The objective of the study was to evaluate the association between GH treatment and the development of CNS-SNs.

DESIGN

The study was designed with a retrospective cohort with longitudinal follow-up.

SETTING

The setting of the study was multiinstitutional.

PARTICIPANTS

A total of 12 098 5-year pediatric cancer survivors from the Childhood Cancer Survivor Study, diagnosed with cancer prior to age 21 years, of whom 338 self-reported GH treatment, which was verified through medical record review.

INTERVENTIONS

INTERVENTIONS included subject surveys, medical records abstraction, and pathological review.

OUTCOME MEASURES

Incidence of meningioma, glioma, and other CNS-SNs was measured.

RESULTS

Among GH-treated survivors, 16 (4.7%) developed CNS-SN, including 10 with meningioma and six with glioma. Two hundred three survivors without GH treatment (1.7%) developed CNS-SN, including 138 with meningioma, 49 with glioma, and 16 with other CNS-SNs. The adjusted rate ratio in GH-treated compared with untreated survivors for development of any CNS-SN was 1.0 [95% confidence interval (CI) 0.6-1.8, P = .94], for meningiomas, 0.8 (95% CI 0.4-1.7, P = .61), and for gliomas, 1.9 (95% CI 0.7-4.8, P = .21). Factors associated with meningioma development included female gender (P = .001), younger age at primary cancer diagnosis (P < .001), and CRT/longer time since CRT (P < .001). Glioma was associated with CRT/shorter time since CRT (P < .001).

CONCLUSIONS

There was no statistically significant increased overall risk of the occurrence of a CNS-SN associated with GH exposure. Specifically, occurrence of meningiomas and gliomas were not associated with GH treatment.

Multidisciplinary care of patients with brain tumors

Patients with brain tumors are some of the most complex patients in the medical system, necessitating treatment teams of multiple subspecialists for optimal care. This article examines the roles of these subspecialists, with the goal of summarizing standard-of-care practices, recent therapeutic advances, and ongoing clinical investigations within each subspecialty.

Medulloblastoma

OPINION STATEMENT

The mainstay of medulloblastoma treatment is high-quality interdisciplinary collaboration in diagnosis, treatment, and aftercare by all involved disciplines. The first step in treatment of medulloblastoma is a maximal safe surgery, followed by thorough staging. Surgery should only be performed in experienced neurosurgical centers, with age-appropriate postoperative care. As optimal risk stratification is based on histopathological and neuroradiological assessments, these should be performed or confirmed by experienced specialists. Central review of histopathological subtype, as well as review of staging evaluations is highly desirable. For young children with desmoplastic/nodular (DMB), or extensive nodular medulloblastoma, craniospinal or any radiotherapy should be avoided. For young children with classic medulloblastoma (CMB), large cell, or anaplastic medulloblastoma (LC/A MB) optimized strategies with high-dose chemotherapy and autologous stem cell rescue with or without local radiotherapy are under investigation. For older clinical standard risk patients (without metastases, without postoperative residual tumor >1.5 cm(2)) with CMB or DMB, craniospinal radiotherapy with 23.4 Gy and boost to the posterior fossa to 54 Gy, followed by maintenance chemotherapy can be regarded as a standard therapy besides other currently applied regimen, such as the use of intensified chemotherapy after irradiation. Older children with LC/A MB, metastatic medulloblastoma, and/or large residual tumor can be regarded as high-risk patients and should receive intensified treatment: intensified chemotherapeutic regimen before or after radiotherapy with increased dose (36-Gy CSI normofractionated, or 40-Gy hyperfractionated) is used. For treatment to be effective, quality control of radiotherapy is of high relevance. Information on long-term sequelae is essential and appropriate multidisciplinary follow-up and support, including rehabilitation and help for reintegration, is necessary. Whenever possible, patients should be included in prospective studies, and tumor material should be sampled to facilitate further research on medulloblastoma biology, which will significantly influence the stratification criteria and the introduction of targeted therapies in standard treatment recommendations in the future.

Medulloblastomas: update on a heterogeneous disease

PURPOSE OF REVIEW

Medulloblastoma is the main primitive neuroectodermal tumour of the posterior fossa in childhood. The classical therapeutic approach consists of surgical resection, followed by craniospinal irradiation. Because of the good overall survival (75%), the main recent research efforts focus on refining the most relevant prognostic stratification and in decreasing the long-term sequelae.

RECENT FINDINGS

Thanks to the better understanding of the heterogeneity of medulloblastomas, clinical, histological and biological markers have been clearly identified and allow risk-adapted strategies. A subset of tumours of early childhood (<3-5 years), frequently associated with a Sonic Hedgehog signalling, might be cured without irradiation. In older children, several trials have demonstrated the safety of reduced craniospinal irradiation in standard risk tumours. Furthermore, the evidence of an excellent prognosis associated with a subset of tumours characterized by an activation of the WNT pathway leads to forthcoming de-escalating strategies. Reducing long-term sequelae also relies on new surgical approaches aiming at reducing the cerebellar injuries. Tremendous efforts have also been made in defining the most adapted irradiation doses and fields. Intensity-modulated radiotherapy and proton beam therapy might also influence the long-term neurological and endocrine defects of the patients.

SUMMARY

Histological and biological characteristics clearly define various prognostic groups within medulloblastomas; confirming the overall good outcome and reducing long-term sequelae are the main focus of current clinical trials.

Growth hormone therapy and the risk of tumor recurrence after brain tumor treatment in children

To assess the effect of human growth hormone (hGH) therapy and other factors on tumor recurrence after treatment of pediatric brain tumors (BTs), we retrospectively analyzed data from 108 craniopharyngioma, medulloblastoma, and ependymoma patients. Risk factors were identified using multifactorial univariate regression analysis. Recurrences occurred in 41 and second malignant neoplasms in 4 patients. There were significant correlations for completeness of tumor removal and recurrence-free survival (RFS). 13/44 hGH-treated and 28/59 non-hGH-treated children relapsed. This difference was found only for medulloblastomas and accounted for by higher rates of incomplete tumor removal in non-hGH patients. Craniopharyngioma recurrence correlated only with RFS. Malignant BT recurrence correlated with completeness of tumor removal, chemotherapy, and RFS. 4 children developed SMNs, 3/4 after hGH therapy. Our regression model yielded accurate within-sample prediction of recurrence for 90% of the study population. We conclude that hGH therapy after treatment of pediatric BTs does not increase tumor recurrence risk.

Childhood medulloblastoma: current status of biology and treatment

Medulloblastoma, a primitive neuro-ectodermal tumour that arises in the posterior fossa, is the most common malignant brain tumour occurring in childhood. Over the past half century, the long-term survival for children with medulloblastoma has improved remarkably from a certain fatal diagnosis to a cancer that is often curable. Although overall survival for children with non-disseminated and non-anaplastic medulloblastoma can approach 80%, the current multidisciplinary therapeutic approach is not without long-term sequelae. Chemotherapy has improved the long-term survival and allowed for reductions in the amount of radiation given, thereby reducing some of the long-term toxicities. In this review, we describe the current understanding of the basic biology of medulloblastoma and report on the current active chemotherapeutic agents utilized in medulloblastoma therapy. Ultimately, our understanding of the basic biology of medulloblastoma may lead to further advances in therapy by providing targets that are more specific and potentially less toxic.

Survey of long-term follow-up programs in the United States for survivors of childhood brain tumors

INTRODUCTION

Despite recognition that childhood brain tumor survivors often suffer multiple late effects following therapy, little is known regarding the long-term follow-up (LTFU) programs for these patients.

METHODS

A 16-question survey was mailed to member institutions of the Children's Oncology Group in the United States. Institutions were asked about the size of their brain tumor program, activities of the LTFU programs and perceived barriers to follow-up.

RESULTS

One hundred forty-five (74%) of 197 institutions returned surveys. Care for patients <21 years old at diagnosis who are >2 years following completion of therapy was provided at a designated neuro-oncology LTFU clinic (31.2%), a general LTFU program for childhood cancer survivors (30.4%), or a general pediatric oncology program (29.7%). Institutions with a neuro-oncology LTFU clinic were more likely to use neuro-psychological testing following radiation therapy (P = 0.001), have longer duration of continued surveillance imaging (P = 0.02), use growth hormone replacement for medulloblastoma survivors (P < 0.001) and continue the use of growth hormone into adulthood (P = 0.05) than those with a general pediatric oncology program. Perceived barriers to care of brain tumor survivors included limited access and lack of insurance (32.1%), lack of funding or dedicated time for providers (22.9%), patients' uncertainty about need to follow-up (20.6%), and patients' desire to not be followed in a pediatric cancer program (12.2%).

CONCLUSIONS

Considerable variation exists across institutions in the United States in the delivery of follow-up care for survivors of childhood brain tumors. We encourage additional investigation to better define and implement optimal follow-up care for childhood brain tumor survivors.

Growth hormone supplementation increased latency to tumourigenesis in Atm-deficient mice

Growth hormone (GH) is important for cell growth and differentiation, has multiple effects on lymphoid tissue and may promote blast cell proliferation and cancer development. We studied the effect of GH on longevity and tumour formation in Atm-deficient mice, an established model of the human cancer prone syndrome ataxia telangiectasia (AT). AT is a devastating recessive disorder that is characterized by progressive cerebellar ataxia, immunodeficiency, chromosomal instability and cancer susceptibility. Since AT patients also show endocrinological abnormalities the question has been raised as to whether GH therapy could be beneficial and/or increase the cancer risk in AT. We found that treatment with GH significantly increased longevity of Atm-deficient mice. In addition, GH ameliorated locomotoric behaviour and improved T-cell immunity. Thus, our data demonstrated that GH treatment is not necessarily accompanied by increased cancer development in diseases with chromosomal instability and cancer susceptibility and might be beneficial for AT patients.

Growth hormone treatment and risk of recurrence or progression of brain tumors in children: a review

INTRODUCTION

Brain tumors are one of the most common types of solid neoplasm in children. As life expectancy of these patients has increased with new and improved therapies, the morbidities associated with the treatments and the tumor itself have become more important.

DISCUSSION

One of the most common morbidities is growth hormone deficiency, and since recombinant growth hormone (GH) became available, its use has increased exponentially. There is concern that in the population of children with brain tumors, GH treatment might increase the risk of tumor recurrence or progression or the appearance of a second neoplasm. In the light of this ongoing concern, the current literature has been reviewed to provide an update on the risk of tumor recurrence, tumor progression, or new intracranial tumor formation when GH is used to treat GH deficiency in children, who have had or have intracranial tumors.

CONCLUSION

On the basis of this review, the authors conclude that the use of GH in patients with brain tumor is safe. GH therapy is not associated with an increased risk of central nervous system tumor progression or recurrence, leukemia (de novo or relapse), or extracranial non-leukemic neoplasms.

Pediatric medulloblastoma: toxicity of current treatment and potential role of protontherapy

Post-operative craniospinal irradiation and systemic chemotherapy are both necessary in the treatment of pediatric medulloblastoma. Late toxicity is a major problem in long term survivors and significantly affects their quality of life. We have systematically reviewed the literature to examine data on late toxicity, specifically focusing on: endocrine function, growth and bone development, neurocognitive development, second cancers, ototoxicity, gynecological toxicity and health of the offspring, cardiac toxicity and pulmonary toxicity. In this paper, we describe qualitatively the kind of detected side effects and, whenever possible, try to assess their incidence and the relative role of craniospinal irradiation (as opposed to other treatments and to the disease itself) in producing them. Subsequently we examine the possible approach to reduce unwanted effects from craniospinal irradiation to target and non-target tissues and we consider briefly the role of hyperfractionation, tomotherapy and IMRT. We describe the characteristics of protontherapy and its potential for non-target tissues toxicity reduction reviewing the existing physical and dosimetric studies and the (still very limited) clinical experiences. Finally we propose intensity modulated spot scanning protontherapy with multiportal simultaneous optimization (IMPT) as a possible tool for dose distribution optimization within different areas of CNS and potential reduction of target tissues toxicity.

Aggressive infantile embryonal tumors

Embryonal tumors are the most common brain tumors in infants less than 36 months. Histologically characterized as undifferentiated small, round cell tumors with divergent patterns of differentiation, these include medulloblastoma, the most common form of embryonal tumor, as well as supratentorial primitive neuroectodermal tumor, medulloepithelioma, ependymoblastoma, medullomyoblastoma, melanotic medulloblastoma, and atypical teratoid/rhabdoid tumor. All are similarly aggressive and have a tendency to disseminate throughout the central nervous system. Because of efforts to avoid craniospinal irradiation in an attempt to lessen treatment-related neurotoxicity, management of these tumors in infants is unique. Outcomes remain similarly poor among all the tumor types and, therefore, identification of specific molecular targets that have prognostic and therapeutic implications is crucial. The molecular and clinical aspects of the 3 most common aggressive infantile embryonal tumors, medulloblastoma, supratentorial primitive neuroectodermal tumor, and atypical teratoid/rhabdoid tumor, are the focus of this review.

Endocrine outcomes for children with embryonal brain tumors after risk-adapted craniospinal and conformal primary-site irradiation and high-dose chemotherapy with stem-cell rescue on the SJMB-96 trial

PURPOSE

To estimate the cumulative incidence of specific hormone deficiencies and the influence of hypothalamic-pituitary (HP) axis radiation dose in a cohort of children with embryonal brain tumors treated with risk-adapted craniospinal irradiation (CSI), conformal primary site irradiation, and high-dose chemotherapy.

PATIENTS AND METHODS

Clinical data and HP axis radiation dosimetry data were obtained from 88 eligible children. All patients received regular endocrine follow-up that included screening tests of thyroid function and stimulation testing for growth hormone deficiency (GHD), and adrenocorticotropin hormone deficiency.

RESULTS

The cumulative incidence of GHD, thyroid-stimulating hormone (TSH) deficiency, adrenocorticotropic hormone deficiency, and primary hypothyroidism at 4 years from diagnosis was 93% +/- 4%, 23% +/- 8%, 38% +/- 6%, and 65% +/- 7%, respectively. Radiation dosimetry to the HP axis was associated only with the development of TSH deficiency; the 4-year cumulative incidence was 44% +/- 19% and 11% +/- 8% (P = .014) for those receiving more or less than the median dose to the hypothalamus (>or= 42 v < 42 Gy), respectively. The median dose of CSI for the average-risk (AR) patients was 23.4 and 39.6 Gy (36 to 40.5 Gy) for the high-risk patients. The estimated mean decline in height Z-score after radiation therapy was greater in high-risk patients (-0.65 units/yr) when compared with AR patients (-0.54 units/yr; P = .039).

CONCLUSION

Pediatric patients with CNS embryonal tumors are at high risk for treatment-related hormone deficiencies. GHD and primary hypothyroidism were diagnosed in a majority of subjects relatively soon after the completion of therapy. Radiation dose to the hypothalamus in excess of 42 Gy was associated with an increase in the risk of developing TSH deficiency.

Developing a health-related quality of life instrument for childhood brain tumor survivors

OBJECTS

With improved treatment, many childhood brain tumor survivors live through adulthood. A psychometrically sound instrument, which can capture their unique experiences through the lifetime, is needed. This paper documents the development of the Pediatric Functional Assessment of Cancer Therapy-Childhood Brain Tumor Survivor (PedsFACT-BrS) for use with survivors for at least 1 year posttreatment.

METHODS

The PedsFACT-BrS was developed in two phases. In phase I, items were generated via interviewing 20 survivors, 20 caregivers, and 12 clinicians/teachers. In phase II, Rasch analysis and classical test theory were used to evaluate the responses of 46 survivors and 46 caregivers.

CONCLUSION

The 34-item PedsFACT-BrS covers four domains: physical well-being, emotional well-being and illness experiences, social well-being, and brain tumor-specific concerns. Its scalability is supported by Rasch analysis and its content validity and reliability is documented. It is now ready to be validated to other subpopulations across the disease trajectory.