National Cancer Institute Workshop on Proton Therapy for Children: Considerations Regarding Brainstem Injury

PURPOSE

Proton therapy can allow for superior avoidance of normal tissues. A widespread consensus has been reached that proton therapy should be used for patients with curable pediatric brain tumor to avoid critical central nervous system structures. Brainstem necrosis is a potentially devastating, but rare, complication of radiation. Recent reports of brainstem necrosis after proton therapy have raised concerns over the potential biological differences among radiation modalities. We have summarized findings from the National Cancer Institute Workshop on Proton Therapy for Children convened in May 2016 to examine brainstem injury.

METHODS AND MATERIALS

Twenty-seven physicians, physicists, and researchers from 17 institutions with expertise met to discuss this issue. The definition of brainstem injury, imaging of this entity, clinical experience with photons and photons, and potential biological differences among these radiation modalities were thoroughly discussed and reviewed. The 3 largest US pediatric proton therapy centers collectively summarized the incidence of symptomatic brainstem injury and physics details (planning, dosimetry, delivery) for 671 children with focal posterior fossa tumors treated with protons from 2006 to 2016.

RESULTS

The average rate of symptomatic brainstem toxicity from the 3 largest US pediatric proton centers was 2.38%. The actuarial rate of grade ≥2 brainstem toxicity was successfully reduced from 12.7% to 0% at 1 center after adopting modified radiation guidelines. Guidelines for treatment planning and current consensus brainstem constraints for proton therapy are presented. The current knowledge regarding linear energy transfer (LET) and its relationship to relative biological effectiveness (RBE) are defined. We review the current state of LET-based planning.

CONCLUSIONS

Brainstem injury is a rare complication of radiation therapy for both photons and protons. Substantial dosimetric data have been collected for brainstem injury after proton therapy, and established guidelines to allow for safe delivery of proton radiation have been defined. Increased capability exists to incorporate LET optimization; however, further research is needed to fully explore the capabilities of LET- and RBE-based planning.

A pediatric brain tumor consortium phase II trial of capecitabine rapidly disintegrating tablets with concomitant radiation therapy in children with newly diagnosed diffuse intrinsic pontine gliomas

BACKGROUND

We conducted a phase II study of oral capecitabine rapidly disintegrating tablets given concurrently with radiation therapy (RT) to assess progression-free survival (PFS) in children with newly diagnosed diffuse intrinsic pontine gliomas (DIPG).

PATIENTS AND METHODS

Children 3-17 years with newly diagnosed DIPG were eligible. Capecitabine, 650 mg/m² /dose BID (maximum tolerated dose [MTD] in children with concurrent radiation), was administered for 9 weeks starting the first day of RT. Following a 2-week break, three courses of capecitabine, 1,250 mg/m² /dose BID for 14 days followed by a 7-day rest, were administered. As prospectively designed, 10 evaluable patients treated at the MTD on the phase I trial were included in the phase II analyses. The design was based on comparison of the PFS distribution to a contemporary historical control (n = 140) with 90% power to detect a 15% absolute improvement in the 1-year PFS with a type-1 error rate, α = 0.10.

RESULTS

Forty-four patients were evaluable for the phase II objectives. Capecitabine and RT was well tolerated with low-grade palmar plantar erythrodyesthesia, increased alanine aminotransferase, cytopenias, and vomiting the most commonly reported toxicities. Findings were significant for earlier progression with 1-year PFS of 7.21% (SE = 3.47%) in the capecitabine-treated cohort versus 15.59% (SE = 3.05%) in the historical control (P = 0.007), but there was no difference for overall survival (OS) distributions (P = 0.30). Tumor enhancement at diagnosis was associated with shorter PFS and OS. Capecitabine was rapidly absorbed and converted to its metabolites.

CONCLUSION

Capecitabine did not improve the outcome for children with newly diagnosed DIPG.

Late outcomes of adult survivors of childhood non-Hodgkin lymphoma: A report from the St. Jude Lifetime Cohort Study

BACKGROUND

Survivors of childhood non-Hodgkin lymphoma (NHL) are at increased risk for chronic health conditions. The objective of this study was to characterize health conditions, neurocognitive function, and physical performance among a clinically evaluated cohort of 200 childhood NHL survivors.

METHOD

Chronic health and neurocognitive conditions were graded as per a modified version of the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) and impaired physical function defined as performance < 10th percentile of normative data. Multivariable regression was used to investigate associations between sociodemographic characteristics, therapeutic exposures, and outcomes.

RESULTS

Survivors were a median age of 10 years (range 1-19) at diagnosis and 34 years (range 20-58) at evaluation. Eighty-eight (44%) received radiation, 46 (23%) cranial radiation, and 69 (35%) high-dose methotrexate. Most prevalent CTCAE Grades 3-4 (severe life-threatening) conditions were obesity (35%), hypertension (9%), and impairment of executive function (13%), attention (9%), and memory (4%). Many had impaired strength (48%), flexibility (39%), muscular endurance (36%), and mobility (36%). Demographic and treatment-related factors were associated with the development of individual chronic diseases and functional deficits.

CONCLUSIONS

Clinical evaluation identified a high prevalence of chronic health conditions, neurocognitive deficits, and performance limitations in childhood NHL survivors.

A phase 1 and pharmacokinetic study of enzastaurin in pediatric patients with refractory primary central nervous system tumors: a pediatric brain tumor consortium study

BACKGROUND

We sought to estimate the maximum tolerated or recommended phase 2 dose and describe the pharmacokinetics and toxicities of enzastaurin, an oral inhibitor of protein kinase Cβ, in children with recurrent central nervous system malignancies.

METHODS

Enzastaurin was administered continuously once daily at 3 dose levels (260, 340, and 440 mg/m(2)) and twice daily at 440 mg/m(2)/day. Plasma pharmacokinetics were evaluated following a single dose and at steady state. Inhibition of protein kinase C and Akt cell signaling in peripheral blood mononuclear cells was evaluated. Akt pathway activity was measured in pretreatment tumor samples.

RESULTS

Thirty-three patients enrolled; 1 was ineligible, and 3 were nonevaluable secondary to early progressive disease. There were no dose-limiting toxicities during the dose-finding phase. Two participants receiving 440 mg/m(2) given twice daily experienced dose-limiting toxicities of grade 3 thrombocytopenia resulting in delayed start of course 2 and grade 3 alanine transaminase elevation that did not recover within 5 days. There were no grade 4 toxicities during treatment. The concentration of enzastaurin increased with increasing dose and with continuous dosing; however, there was not a significant difference at the 440 mg/m(2) dosing level when enzastaurin was administered once daily versus twice daily. There were no objective responses; however, 11 participants had stable disease >3 cycles, 7 with glioma, 2 with ependymoma, and 2 with brainstem glioma.

CONCLUSION

Enzastaurin was well tolerated in children with recurrent CNS malignancies, with chromaturia, fatigue, anemia, thrombocytopenia, and nausea being the most common toxicities. The recommended phase 2 dose is 440 mg/m(2)/day administered once daily.

18F-FDG PET and MR imaging associations across a spectrum of pediatric brain tumors: a report from the pediatric brain tumor consortium

The purpose of this study was to describe (18)F-FDG uptake across a spectrum of pediatric brain tumors and correlate (18)F-FDG PET with MR imaging variables, progression-free survival (PFS), and overall survival (OS).

METHODS

A retrospective analysis was conducted of children enrolled in phase I/II clinical trials through the Pediatric Brain Tumor Consortium from August 2000 to June 2010. PET variables were summarized within diagnostic categories using descriptive statistics. Associations of PET with MR imaging variables and PFS and OS by tumor types were evaluated.

RESULTS

Baseline (18)F-FDG PET was available in 203 children; 66 had newly diagnosed brain tumors, and 137 had recurrent/refractory brain tumors before enrolling in a Pediatric Brain Tumor Consortium trial. MR imaging was performed within 2 wk of PET and before therapy in all cases. The (18)F-FDG uptake pattern and MR imaging contrast enhancement (CE) varied by tumor type. On average, glioblastoma multiforme and medulloblastoma had uniform, intense uptake throughout the tumor, whereas brain stem gliomas (BSGs) had low uptake in less than 50% of the tumor and ependymoma had low uptake throughout the tumor. For newly diagnosed BSG, correlation of (18)F-FDG uptake with CE portended reduced OS (P = 0.032); in refractory/recurrent BSG, lack of correlation between (18)F-FDG uptake and CE suggested decreased PFS (P = 0.023). In newly diagnosed BSG for which more than 50% of the tumor had (18)F-FDG uptake, there was a suggestion of lower apparent diffusion coefficient (P = 0.061) and decreased PFS (P = 0.065).

CONCLUSION

(18)F-FDG PET and MR imaging showed a spectrum of patterns depending on tumor type. In newly diagnosed BSG, the correlation of (18)F-FDG uptake and CE suggested decreased OS, likely related to more aggressive disease. When more than 50% of the tumor had (18)F-FDG uptake, the apparent diffusion coefficient was lower, consistent with increased cellularity. In refractory/recurrent BSG, poor correlation between (18)F-FDG uptake and CE was associated with decreased PFS, which may reflect concurrent tissue breakdown at sites of treated disease and development of new sites of (18)F-FDG-avid malignancy.

A phase I trial of veliparib (ABT-888) and temozolomide in children with recurrent CNS tumors: a pediatric brain tumor consortium report

BACKGROUND

A phase I trial of veliparib (ABT-888), an oral poly(ADP-ribose) polymerase (PARP) inhibitor, and temozolomide (TMZ) was conducted in children with recurrent brain tumors to (i) estimate the maximum tolerated doses (MTDs) or recommended phase II doses (RP2Ds) of veliparib and TMZ; (ii) describe the toxicities of this regimen; and (iii) evaluate the plasma pharmacokinetic parameters and extent of PARP inhibition in peripheral blood mononuclear cells (PBMCs) following veliparib.

METHODS

TMZ was given once daily and veliparib twice daily for 5 days every 28 days. Veliparib concentrations and poly(ADP-ribose) (PAR) levels in PBMCs were measured on days 1 and 4. Analysis of pharmacokinetic and PBMC PAR levels were performed twice during study conduct to rationally guide dose modifications and to determine biologically optimal MTD/RP2D.

RESULTS

Twenty-nine evaluable patients were enrolled. Myelosuppression (grade 4 neutropenia and thrombocytopenia) were dose limiting. The RP2Ds are veliparib 25 mg/m(2) b.i.d. and TMZ 135 mg/m(2)/d. Only 2 out of 12 patients treated at RP2Ds experienced dose-limiting toxicities. Although no objective response was observed, 4 patients had stable disease >6 months in duration, including 1 with glioblastoma multiforme and 1 with ependymoma. At the RP2D of veliparib, pediatric pharmacokinetic parameters were similar to those in adults.

CONCLUSIONS

Veliparib and TMZ at the RP2D were well tolerated in children with recurrent brain tumors. A phase I/II trial to evaluate the tolerability and efficacy of veliparib, TMZ, and radiation in children with newly diagnosed brainstem gliomas is in progress.

High-risk medulloblastoma: a pediatric oncology group randomized trial of chemotherapy before or after radiation therapy (POG 9031)

PURPOSE

To compare event-free survival (EFS) in children with high-risk medulloblastoma randomly assigned to receive either chemotherapy before radiation or chemotherapy after radiation.

PATIENTS AND METHODS

One hundred twelve patients were randomly assigned to each arm. Criteria used to categorize patients as high risk included M1-4 disease by modified Chang staging classification, T3b/T4 disease, or greater than 1.5 cm3 of residual tumor after surgery. Postoperatively, children with high-risk medulloblastoma were randomly assigned to two arms, either chemotherapy entailing three cycles of cisplatin and etoposide before radiation (chemotherapy first [CT1]) or the same chemotherapy regimen after radiation (radiation therapy first [RT1]). Both groups received consolidation chemotherapy consisting of vincristine and cyclophosphamide.

RESULTS

The median follow-up time was 6.4 years. Five-year EFS was 66.0% in the CT1 arm and 70.0% in the RT1 arm (P = .54), and 5-year overall survival in the two groups was 73.1% and 76.1%, respectively (P = .47). In the CT1 arm, 40 of the 62 patients with residual disease achieved either complete or partial remission.

CONCLUSION

Five-year EFS did not differ significantly whether, after surgery, patients received chemotherapy before or after radiotherapy.

Evaluation of memory impairment in aging adult survivors of childhood acute lymphoblastic leukemia treated with cranial radiotherapy

BACKGROUND

Cranial radiotherapy (CRT) is a known risk factor for neurocognitive impairment in survivors of childhood cancer and may increase risk for mild cognitive impairment and dementia in adulthood.

METHODS

We performed a cross-sectional evaluation of survivors of childhood acute lymphoblastic leukemia (ALL) treated with 18 Gy (n = 127) or 24 Gy (n = 138) CRT. Impairment (age-adjusted score >1 standard deviation below expected mean, two-sided exact binomial test) on the Wechsler Memory Scale IV (WMS-IV) was measured. A subset of survivors (n = 85) completed structural and functional neuroimaging.

RESULTS

Survivors who received 24 Gy, but not 18 Gy, CRT had impairment in immediate (impairment rate = 33.8%, 95% confidence interval [CI] = 25.9% to 42.4%; P < .001) and delayed memory (impairment rate = 30.2%, 95% CI = 22.6% to 38.6%; P < .001). The mean score for long-term narrative memory among survivors who received 24 Gy CRT was equivalent to that for individuals older than 69 years. Impaired immediate memory was associated with smaller right (P = .02) and left (P = .008) temporal lobe volumes, and impaired delayed memory was associated with thinner parietal and frontal cortices. Lower hippocampal volumes and increased functional magnetic resonance imaging activation were observed with memory impairment. Reduced cognitive status (Brief Cognitive Status Exam from the WMS-IV) was identified after 24 Gy (18.5%, 95% CI = 12.4% to 26.1%; P < .001), but not 18 Gy (8.7%, 95% CI = 4.4% to 15.0%; P = .11), CRT, suggesting a dose-response effect. Employment rates were equivalent (63.8% for 24 Gy CRT and 63.0% for 18 Gy CRT).

CONCLUSIONS

Adult survivors who received 24 Gy CRT had reduced cognitive status and memory, with reduced integrity in neuroanatomical regions essential in memory formation, consistent with early onset mild cognitive impairment.

Phase I trial of capecitabine rapidly disintegrating tablets and concomitant radiation therapy in children with newly diagnosed brainstem gliomas and high-grade gliomas

BACKGROUND

We conducted a phase I study to estimate the maximum tolerated dose and describe the dose-limiting toxicities and pharmacokinetics of oral capecitabine rapidly disintegrating tablets given concurrently with radiation therapy to children with newly diagnosed brainstem or high-grade gliomas.

METHODS

Children 3-21 y with newly diagnosed intrinsic brainstem or high-grade gliomas were eligible for enrollment. The starting dose was 500 mg/m(2), given twice daily, with subsequent cohorts enrolled at 650 mg/m(2) and 850 mg/m(2) using a 3 + 3 phase I design. Children received capecitabine at the assigned dose daily for 9 wks starting from the first day of radiation therapy (RT). Following a 2-wk break, patients received 3 courses of capecitabine 1250 mg/m(2) twice daily for 14 days followed by a 7-day rest. Pharmacokinetic sampling was performed in consenting patients. Six additional patients with intrinsic brainstem gliomas were enrolled at the maximum tolerated dose to further characterize the pharmacokinetic and toxicity profiles.

RESULTS

Twenty-four patients were enrolled. Twenty were fully assessable for toxicity. Dose-limiting toxicities were palmar plantar erythroderma (grades 2 and 3) and elevation of alanine aminotransferase (grades 2 and 3). Systemic exposure to capecitabine and metabolites was similar to or slightly lower than predicted based on adult data.

CONCLUSIONS

Capecitabine with concurrent RT was generally well tolerated. The recommended phase II capecitabine dose when given with concurrent RT is 650 mg/m(2), administered twice daily. A phase II study to evaluate the efficacy of this regimen in children with intrinsic brainstem gliomas is in progress (PBTC-030).

A phase-1 pharmacokinetic optimal dosing study of intraventricular topotecan for children with neoplastic meningitis: a Pediatric Brain Tumor Consortium study

PURPOSE

We performed a phase-1 pharmacokinetic optimal dosing study of intraventricular topotecan (IT), administered daily 5×, to determine whether, the maximum tolerated dose of IT topotecan was also the pharmacokinetic optimal dose.

PATIENTS AND METHODS

Patients received topotecan administered through an intraventricular access device (0.1 or 0.2 mg/dose), daily × 5 every other week 2× (Induction); every 3 weeks × 2 (Consolidation); then every 4 weeks for up to 11 courses (Maintenance). Ventricular CSF pharmacokinetic studies were performed on day 1, week 1 of induction, and in a subset of patients after a single intralumbar topotecan dose on day 1, week 3.

RESULTS

Nineteen patients were enrolled. All were evaluable for toxicity and 18 were assessable for pharmacokinetics. Arachnoiditis requiring corticosteroid therapy occurred in or one of three patients at the 0.1 mg dose level and two of the initial three patients enrolled at the 0.2 mg dose level. All subsequent patients were therefore treated with concomitant dexamethasone. Pharmacokinetic evaluation after accrual of the first seven patients revealed that a topotecan lactone concentration >1 ng/ml for 8 hours was attained in all patients and thus, further dose escalation was not pursued. Results of simulation studies showed that at the dose levels evaluated, >99.9% of patients are expected to achieve CSF topotecan lactone concentrations >1 ng/ml for at least 8 hours.

CONCLUSION

Intraventricular topotecan, 0.2 mg, administered daily for 5 days with concomitant dexamethasone is well tolerated and was defined to be the pharmacokinetic optimal dose in this trial.

Pilot study of systemic and intrathecal mafosfamide followed by conformal radiation for infants with intracranial central nervous system tumors: a pediatric brain tumor consortium study (PBTC-001)

A pilot study to investigate the feasibility of the addition of intrathecal (IT) mafosfamide to a regimen of concomitant multi-agent systemic chemotherapy followed by conformal radiation therapy (RT) for children <3 years with newly diagnosed embryonal CNS tumors was performed. Ninety-three newly diagnosed infants and children (<3 years) with embryonal CNS tumors were enrolled. Twenty weeks of systemic multi-agent chemotherapy commenced within 35 days of surgery. Patients without CSF flow obstruction (n = 71) received IT mafosfamide (14 mg) with chemotherapy. Localized (M(0)) patients with SD or better subsequently received RT followed by 20 additional weeks of chemotherapy. Second look surgery was encouraged prior to RT if there was an incomplete surgical resection at diagnosis. 71 evaluable patients with normal CSF flow received IT Mafosfamide with systemic chemotherapy; patients with M + disease were removed from protocol therapy at 20 weeks and those with PD at the time of progression. One and 5-year progression free survival (PFS) and overall survival (OS) for the cohort of 71 evaluable patients were 52 ± 6.5 % and 33 ± 13 %, and 67 ± 6.2 % and 51 ± 11 %, respectively. The 1-year Progression Free Survival (PFS) for M0 patients with medulloblastoma (MB, n = 20), supratentorial primitive neuroectodermal tumor (PNET, n = 9), and atypical teratoid rhabdoid tumor (ATRT, n = 12) was 80 ± 7 %, 67 ± 15 % and 27 ± 13 % and 5-year PFS was 65 ± 19 %, 37 ± 29 %, and 0 ± 0 %, respectively. The addition of IT mafosfamide to systemic chemotherapy in infants with embryonal CNS tumors was feasible. The PFS for M0 patients appears comparable to or better than most prior historical comparisons and was excellent for those receiving conformal radiotherapy.

Dose intensive melphalan and cyclophosphamide with autologous hematopoietic stem cells for recurrent medulloblastoma or germinoma

PURPOSE

To determine the response, toxicity, and survival for children with progressive or recurrent medulloblastoma and germinoma using a single myeloablative course of chemotherapy supported by autologous hematopoietic stem cells.

PATIENTS AND METHODS

Subjects were in second remission or had minimal residual disease at the time of study entry. The conditioning regimen consisted of cyclophosphamide 6,000 mg/m(2) plus melphalan 180 mg/m(2).

RESULTS

Twenty-nine evaluable pediatric patients were accrued. The most frequent major toxicities were myelosuppression, infections, and stomatitis, but no toxic deaths were recorded. Best responses were: CR = 6, CCR = 13, PR = 6, SD = 2, and PD = 2. There were 6 medulloblastoma and 3 germinoma survivors with a median follow-up of 7.5 years (range = 2.8-10). Two germinoma survivors received radiotherapy after autografting for presumptive progressive disease.

CONCLUSION

Myeloablative chemotherapy consisting of cyclophosphamide and melphalan was tolerable in the relapsed brain tumor setting with 19/29 cases achieving CR or CCR status and 9/29 becoming long-term survivors.

Establishment and results of a magnetic resonance quality assurance program for the pediatric brain tumor consortium

RATIONALE AND OBJECTIVES

Magnetic resonance (MR) imaging is used to assess brain tumor response to therapies, and a MR quality assurance (QA) program is necessary for multicenter clinical trials employing imaging. This study was performed to determine overall variability of quantitative imaging metrics measured with the American College of Radiology (ACR) phantom among 11 sites participating in the Pediatric Brain Tumor Consortium (PBTC) Neuroimaging Center (NIC) MR QA program.

MATERIALS AND METHODS

An MR QA program was implemented among 11 participating PBTC sites and quarterly evaluations of scanner performance for seven imaging metrics defined by the ACR were sought and subject to statistical evaluation over a 4.5-year period. Overall compliance with the QA program, means, standard deviations, and coefficients of variation (CV) for the quantitative imaging metrics were evaluated.

RESULTS

Quantitative measures of the seven imaging metrics were generally within ACR recommended guidelines for all sites. Compliance improved as the study progressed. Intersite variabilities, as gauged by CV for slice thickness and geometric accuracy, imaging parameters that influence size or positioning measurements in tumor studies, were on the order of 10% and 1%, respectively.

CONCLUSIONS

Although challenging to establish, MR QA programs within the context of PBTC multisite clinical trials when based on the ACR MR phantom program can indicate sites performing below acceptable image quality levels and establish levels of precision through instrumental variabilities that are relevant to quantitative image analyses (eg, tumor volume changes).

Endocrine outcome for children with embryonal brain tumors treated with craniospinal irradiation on the SJMB96 trial

9571

Background: To investigate the relationship between endocrine deficits with the radiation (RT) dose to the hypothalamic- pituitary axis (HPA) in medulloblastoma/PNET patients treated with risk-adapted craniospinal irradiation (CSI) followed by chemotherapy. Methods: 88 patients who survived at least 2 years from diagnosis were included in this analysis. CSI doses were 23.4 Gy or 36–39.6 Gy depending on clinical risk; the primary tumor site received 55.8 Gy. All pts had regular endocrine follow-up and screening to test for growth hormone (GH), thyroid hormone (TH) and adrenocorticotrophin hormone (ACTH) deficiency. Patients that had abnormal results on the screening tests underwent further evaluation by stimulation testing of the HPA. Only patients diagnosed with central hypothyroidism were included in the analysis for TH deficiency. Results: Of the 88 pts included in the study cohort, 77 pts had abnormal screening tests and underwent provocative testing. The median radiation dose to the hypothalamus was 42 Gy (26–57 Gy) and pituitary was 44 Gy (26–58 Gy). Patients receiving higher RT doses to the pituitary had a significantly higher incidence of growth hormone deficiency with 4-year estimates of 100 ±3% for those receiving = 44Gy and 82±7% for those receiving < 44 Gy (p=0.024). Four-year estimates of thyroid hormone deficiency for patients receiving = 44 Gy to the pituitary were 67±21% and 18±14% for those receiving < 44 Gy (p<0.010). There was no correlation between the dose to the pituitary with the incidence of ACTH deficiency. The estimated change in height z-score for patients receiving < 44 Gy to the pituitary was - 0.53 units per year (-0.44 to -0.63) compared with -0.70 units per year (-0.62 to -0.78) for those receiving = 44 Gy. Conclusions: Data from this prospective study demonstrate that RT to the HPA is the key determinant for developing endocrinopathies in patients with medulloblastoma/PNET.

No significant financial relationships to disclose.

Radiotherapy in pediatric medulloblastoma: Quality assessment of Pediatric Oncology Group Trial 9031

PURPOSE

To evaluate the potential influence of radiotherapy quality on survival in high-risk pediatric medulloblastoma patients.

METHODS AND MATERIALS

Trial 9031 of the Pediatric Oncology Group (POG) aimed to study the relative benefit of cisplatin and etoposide randomization of high-risk patients with medulloblastoma to preradiotherapy vs. postradiotherapy treatment. Two-hundred and ten patients were treated according to protocol guidelines and were eligible for the present analysis. Treatment volume (whole brain, spine, posterior fossa, and primary tumor bed) and dose prescription deviations were assessed for each patient. An analysis of first site of failure was undertaken. Event-free and overall survival rates were calculated. A log-rank test was used to determine the significance of potential survival differences between patients with and without major deviations in the radiotherapy procedure.

RESULTS

Of 160 patients who were fully evaluable for all treatment quality parameters, 91 (57%) had 1 or more major deviations in their treatment schedule. Major deviations by treatment site were brain (26%), spinal (7%), posterior fossa (40%), and primary tumor bed (17%). Major treatment volume or total dose deviations did not significantly influence overall and event-free survival.

CONCLUSIONS

Despite major treatment deviations in more than half of fully evaluable patients, underdosage or treatment volume misses were not associated with a worse event-free or overall survival.

Natural history of thyroid nodules in survivors of pediatric Hodgkin lymphoma

BACKGROUND

Survivors of Hodgkin lymphoma and other patients who receive neck irradiation are at increased risk of thyroid cancer. Ultrasonography provides an inexpensive and non-invasive method of thyroid screening, but the clinical significance of thyroid nodules detected by ultrasound screening is uncertain.

PROCEDURE

We reviewed the demographics, clinical characteristics, method of detection, and outcome of patients who developed thyroid nodules after treatment for pediatric Hodgkin lymphoma at our institution. One radiologist reviewed all imaging studies.

RESULTS

Sixty-seven children treated for Hodgkin lymphoma from 1962 to 2001 developed thyroid nodules. The study group represented 9,024 person-years of follow-up after the diagnosis of Hodgkin lymphoma and 581 person-years after diagnosis of a thyroid nodule. A median of 10.5 years (range, 0.2-24.8 years) elapsed between the diagnoses of Hodgkin lymphoma and thyroid nodule(s). All but one patient had received neck irradiation for Hodgkin lymphoma, with a median thyroid radiation dose of 35 Gy (range, 12-45 Gy). Thyroid nodules were found to be malignant in seven patients (10%), at a median of 16.2 years (range, 8.4-23.7 years) after diagnosis of Hodgkin lymphoma. Only one malignancy was found through screening ultrasonography. All patients with thyroid cancer remained disease-free at 0.4-16.2 years of follow-up.

CONCLUSIONS

Thyroid nodules are common in Hodgkin lymphoma survivors treated with neck irradiation, but the majority of these lesions have an indolent clinical course and do not undergo malignant transformation. Only patients with a palpable mass or clinical symptoms need more extensive evaluation, including Doppler-flow ultrasonography and fine-needle aspiration.

Polar spongioblastoma of the spinal cord: a case report

"Rhythmic palisading" is a striking histologic pattern infrequently encountered in a variety of central nervous system (CNS) tumors. We present the case of an infant with a large spinal cord lesion wherein all sampled tissue showed columnar arrangements of palisaded cells, typical of polar spongioblastoma. The tumor was briskly proliferative, focally necrotic, and variably expressed S100, glial fibrillary acidic protein, neuron specific enolase, and p53 by immunohistochemistry. Fluorescence in situ hybridization failed to reveal isochromosome 17q, EGFR amplification, or deletions of 1p, 19q, 22q11.2, 10q, or p16. Despite chemotherapy and decadron, he developed lesional necrosis and intracranial metastases and died less than 1 mo from presentation. This case illustrates polar spongioblastoma as a distinctive histologic pattern that can occur in embryonal CNS tumors. Discrimination of these rare aggressive lesions from other CNS tumors with focal palisaded architecture is crucial as the treatment and prognosis of the latter may differ significantly.

Neurocognitive consequences of risk-adapted therapy for childhood medulloblastoma

PURPOSE

This prospective, longitudinal study examined the effects of risk-adapted craniospinal irradiation (CSI) dose and the interactions of dose with age and time from diagnosis on intelligence quotient (IQ) and academic achievement (reading, spelling, and math) among patients treated for medulloblastoma (MB).

PATIENTS AND METHODS

Patients received serial neurocognitive testing spanning from 0 to 6.03 years after diagnosis (median, 3.14 years). The multi-institutional study included 111 patients, who were 3 to 20 years of age at diagnosis (median age, 7.4 years), treated for MB with risk-adapted CSI followed by four cycles of high-dose chemotherapy (cyclophosphamide, cisplatin, and vincristine) with stem-cell support. High-risk patients (HR; n = 37) received CSI to 36 to 39.6 Gy and conformal boost treatment of the primary site to 55.8 to 59.4 Gy. Average-risk patients (AR; n = 74) received CSI to 23.4 Gy and conformal boost treatment of the posterior fossa to 36.0 Gy and primary site to 55.8 Gy.

RESULTS

Multivariate modeling revealed statistically significant declines in mean IQ (-1.59 points/yr; P = .006), reading (-2.95 points/yr; P < .0001), spelling (-2.94 points/yr; P < .0001), and math (-1.87 points/yr; P = .003) scores for the entire group. The effects of risk-adapted radiation therapy on IQ, reading, and spelling were moderated by age, with the greatest rates of decline observed for the HR patients who were younger (< 7 years old) at diagnosis.

CONCLUSION

Young age at diagnosis was the most prominent risk factor for neurocognitive deficits among survivors of MB despite reductions in CSI dosing and efforts to limit the boost volume. Younger patients exhibited substantial problems with the development of reading skills.

Phase I Clinical Trial of Mafosfamide in Infants and Children Aged 3 Years or Younger With Newly Diagnosed Embryonal Tumors: A Pediatric Brain Tumor Consortium Study (PBTC-001)

Purpose

A phase I trial of intrathecal (IT) mafosfamide was performed to determine the optimal dose, dose-limiting toxicities, and incidence and severity of other toxicities when administered in association with concomitant multiagent systemic chemotherapy to children younger than 3 years with newly diagnosed embryonal tumors.

Patients and Methods

Twenty-five assessable patients received IT mafosfamide at one of six dose levels ranging from 5 mg to 17 mg. Patients were premedicated with dexamethasone (0.15 mg/kg) and morphine (0.1 mg/kg) before receiving IT mafosfamide. Serial samples of CSF for pharmacokinetic studies were obtained in a subset of patients with Ommaya reservoirs.

Results

Irritability, presumably secondary to pain or headache during mafosfamide administration, was dose limiting in two of three patients at the 17-mg dose level. The maximum-tolerated dose of IT mafosfamide following premedication with dexamethasone and morphine was 14 mg.

Conclusion

The maximum tolerated dose and recommended phase II dose of IT mafosfamide in patients younger than 3 years with newly diagnosed embryonal CNS tumors is 14 mg. A trial to assess the efficacy of regional therapy with IT mafosfamide administered with intensive systemic chemotherapy in children younger than 3 years with primary intracranial embryonal tumors is now in progress.

Risk-adapted, combined-modality therapy with VAMP/COP and response-based, involved-field radiation for unfavorable pediatric Hodgkin's disease

PURPOSE

To evaluate the efficacy of vinblastine, doxorubicin, methotrexate, and prednisone (VAMP) and cyclophosphamide, vincristine, and procarbazine (COP) chemotherapy and response-based, involved-field radiation, a combined-modality regimen that limits doses of alkylating agents, anthracyclines, and radiation, in children with advanced and unfavorable Hodgkin's disease.

PATIENTS AND METHODS

From 1993 to 2000, 159 children and adolescents with unfavorable Hodgkin's disease received three alternating cycles (total of six cycles) of VAMP/COP chemotherapy followed by response-based, involved-field radiation therapy: 15 Gy was administered to patients achieving a complete response, and 25.5 Gy was administered to those achieving a partial response after the first two cycles of chemotherapy and to all sites of bulky lymphadenopathy. Unfavorable disease was defined as clinical stage I and II with bulky peripheral nodal disease greater than 6 cm, initial bulky mediastinal mass 33% or more of the intrathoracic diameter, and/or "B" symptoms and all stage III and IV.

RESULTS

Study enrollment was closed after an interim analysis estimated a 5-year event-free survival (EFS) rate below a predefined level. Disease presentation was localized (stage I/II) in 77 patients (48.4%) and advanced (stage III/IV) in 82 patients (51.6%). At a median follow-up of 5.8 years (range, 1.3 to 10.0 years), 38 patients had events, including relapse/progression (n = 35), second malignancy (n = 2), and accidental death (n = 1); nine relapses (25.7%) occurred greater than 4 years from diagnosis. Five-year survival and EFS estimates are 92.7% +/- 2.5% and 75.6% +/- 4.1%, respectively.

CONCLUSION

Risk-adapted combined-modality therapy with VAMP/COP and response-based, involved-field radiation therapy results in an unsatisfactory outcome for pediatric patients with unfavorable presentations of Hodgkin's disease.

Clinically evident venous thromboembolic events in children with brain tumors

We evaluated the incidence and significance of central venous access device dysfunction and symptomatic major thrombosis in 253 pediatric patients with brain tumors. Central venous access device dysfunction was a common complication (28.4%) and was associated with major thrombosis development and a reduced overall survival rate. Major thrombosis was relatively uncommon (2.8%).

Medullomyoblastoma: a radiographic and clinicopathologic analysis of six cases and review of the literature

BACKGROUND

Medullomyoblastoma (MMB) is a rare cerebellar embryonal neoplasm that occurs almost exclusively in children. It is biphasic by microscopy, containing myoblastic and primitive neuroectodermal components.

METHODS

The authors conducted a retrospective review of the radiographic and pathologic characteristics, treatment, and clinical outcomes of six children with MMB who were treated at St. Jude Children's Research Hospital (Memphis, TN) between 1984 and 2003. Fluorescence in situ hybridization (FISH) data were available for four children. A literature review also was conducted and focused on imaging and pathologic findings.

RESULTS

The median age at diagnosis was 4.5 years (range, 0.83-7.5 years). Radiographically, all tumors were cerebellar and exhibited variable enhancement, and 50% of tumors had necrotic foci. Three tumors contained discrete, magnetic resonance imaging (MRI) T2-weighted-hypointense/computed tomography (CT)-hyperdense enhancing regions and separate hyperintense/hypodense nonenhancing regions, which correlated microscopically with geographic islands of primitive neuroectodermal and rhabdomyoblastic cells. Large cell/anaplastic (five tumors), nodular/desmoplastic (two tumors), and classic (two tumors) medulloblastoma histologies were encountered either alone (five tumors) or in combination with each other (two tumors). All 4 tumors that were tested exhibited alterations in chromosome 17 or c-myc amplification. All patients underwent macroscopic total resection and subsequently received chemotherapy and craniospinal (five patients) or local conformal (one patient) radiotherapy. At a median follow-up of 92 months (range, 23-187 months), 3 patients remain alive with no evidence of disease, 2 patients have died of disease, and 1 patient has died of secondary acute lymphocytic leukemia.

CONCLUSIONS

The results of the current study demonstrated the frequent correlation of biphasic nodularity (as determined by MRI or CT) with discrete rhabdomyoblastic and primitive neuroectodermal islands (as revealed by microscopy) in MMB. These results also support the view that MMB and medulloblastoma may have common tumorigenic origins, given their similar histologic and molecular features.

Clinical, histopathologic, and molecular markers of prognosis: toward a new disease risk stratification system for medulloblastoma

PURPOSE

To assess the feasibility of performing central molecular analyses of fresh medulloblastomas obtained from multiple institutions and using these data to identify prognostic markers for contemporaneously treated patients.

MATERIALS AND METHODS

Ninety-seven samples of medulloblastoma were collected. Tumor content in samples was judged by frozen section review. Tumor ERBB2 protein and MYCC, MYCN, and TRKC mRNA levels were measured blind to clinical details using Western blotting and real-time polymerase chain reaction, respectively. Histopathologic and clinical review of each case was also performed. All data were subjected to independent statistical analysis.

RESULTS

Sample acquisition and analysis times ranged from 3 to 6 days. Eighty-six samples contained sufficient tumor for analysis, including 38 classic, 30 nodular desmoplastic, and 18 large-cell anaplastic (LCA) medulloblastomas. Protein and mRNA were extracted from 81 and 49 tumors, respectively. ERBB2 was detected in 40% (n=32 of 81) of tumors, most frequently in LCA disease (P=.005), and was independently associated with a poor prognosis (P=.031). A combination of clinical characteristics and ERBB2 expression provided a highly accurate means of discriminating disease risk. One hundred percent (n=26) of children with clinical average-risk, ERBB2-negative disease were alive at 5 years, with a median follow-up of 5.6 years, compared with only 54% for children with average-risk, ERBB2-positive tumors (n=13; P=.0001). TRKC, MYCC, and MYCN expression and histopathologic subtype were not associated with prognosis in this study.

CONCLUSION

Central and rapid molecular analysis of frozen medulloblastomas collected from multiple institutions is feasible. ERBB2 expression and clinical risk factors together constitute a highly accurate disease risk stratification tool.

Clear cell ependymoma: a clinicopathologic and radiographic analysis of 10 patients

BACKGROUND

Clear cell ependymoma (CCE) is an uncommon central nervous system tumor with a predilection for the supratentorial region in children. Histologically, it may mimic oligodendroglioma, central neurocytoma, hemangioblastoma, and renal cell carcinoma.

METHODS

The authors reviewed the clinical, radiographic, and pathologic features, therapy, and outcome in 10 children with CCE who were treated at St. Jude Children's Research Hospital (1984-2003). Fluorescence in situ hybridization (FISH) was performed using 1p/1q, 19p/19q, CEP18/DAL1, and bcr/NF2 probe pairs.

RESULTS

The median patient age at diagnosis was 7.5 years (range, 1-19 years). Tumors occurred supratentorially in 9 of 10 patients. All tumors had rounded nuclei with surrounding, clear halos and at least focal perivascular pseudorosettes. Seven tumors had anaplastic features. No deletions involving 1p, 19q, or NF2 were detected. The tumors from 5 of 7 patients, all with anaplasia, had losses of both CEP18 and DAL-1. Radiographically, all tumors were enhanced, and 9 tumors had associated cysts with enhancing walls. Seven patients underwent gross total resection, which was near total in one patient and subtotal in two patients. Five patients received immediate postoperative local radiotherapy. Three patients were diagnosed initially with pilocytic astrocytoma (one patient) and oligodendroglioma (two patients) and were observed. The progression-free survival and overall survival rates at 5 years were 34% +/- 20% and 75% +/- 19%, respectively. The median follow-up was 37 months (range, 5-239 months). Five patients developed local recurrence within a median of 9 months after diagnosis. Two patients developed extracranial soft tissue and lymph node metastases.

CONCLUSIONS

CCEs were found to have a predilection for extraneural metastases and early recurrence and demonstrate characteristic radiographic features, anaplastic histologic features, and chromosome 18 losses. The authors recommend resection followed by local radiotherapy as the treatment of choice in children.

Prognostic factors for children with Hodgkin's disease treated with combined-modality therapy

PURPOSE

Evaluation of pretreatment factors to identify children at high risk for relapse after combined-modality therapy for Hodgkin's disease.

PATIENTS AND METHODS

From 1990 to 2000, 328 pediatric patients with clinical stage I to IV Hodgkin's disease were treated with chemotherapy and low-dose involved-field radiotherapy on prospective, collaborative, risk-adapted protocols at three institutions. Pretreatment factors were analyzed by univariate and multivariate analysis for prognostic significance for 5-year disease-free survival (DFS) and overall survival (OS).

RESULTS

With a median follow-up of 59 months (range, 8 to 125 months), the 5-year DFS and OS for all patients were 83% and 93%, respectively. Several factors were associated with inferior DFS and OS by univariate analysis. By multivariate analysis, male sex; stage IIB, IIIB, or IV disease; bulky mediastinal disease; WBC more than 13.5 x 10(3)/mm3; and hemoglobin less than 11.0 g/dL were significant for inferior DFS. A prognostic index was developed incorporating the five significant factors from the multivariate analysis, assigning each a score of 1. The 5-year DFS and OS for children with a prognostic score of 0 to 1 were 94% and 99%; score 2, 85% and 96%; score 3, 71% and 92%; and score 4 or 5, 49% and 72%, respectively. There was a significant difference in DFS among each of these groups, with significantly worse OS in those with a score of 4 to 5.

CONCLUSION

A prognostic index that was based on five pretreatment factors correlated with inferior DFS by multivariate analysis stratified patients by outcome; this may be useful in assigning children with Hodgkin's disease to risk-adapted therapy.

VAMP and low-dose, involved-field radiation for children and adolescents with favorable, early-stage Hodgkin's disease: results of a prospective clinical trial

PURPOSE

To evaluate outcome and assess toxicity of children and adolescents with early-stage, favorable Hodgkin's disease treated with vinblastine, doxorubicin, methotrexate, and prednisone (VAMP) and low-dose, involved-field radiation.

PATIENTS AND METHODS

One hundred ten patients with clinical stages I and II, favorable (nonbulky) Hodgkin's disease were treated with four cycles of VAMP chemotherapy and 15 Gy involved-field radiation for those who achieved a complete response, or 25.5 Gy for those who achieved a partial response to two cycles of VAMP.

RESULTS

With a median follow-up of 5.6 years (range, 1.1 to 10.4 years), the 5-year survival and event-free survival were 99% (lower confidence limit [CL], 97.4%) and 93% (lower CL, 88.6%), respectively. Factors associated with event-free survival of 100% were complete response to two cycles of VAMP and histology other than nodular sclerosing Hodgkin's disease (NSHD). No serious early or late toxicity has been observed. Patients presenting with clinical stages I and IIA, nonbulky disease involving fewer than three nodal sites have a projected survival and event-free survival of 100% and 97% (lower CL, 93%), respectively, at 5 years.

CONCLUSION

Risk-adapted, combined-modality therapy using only four cycles of VAMP chemotherapy with 15 to 25.5 Gy of involved-field radiation for patients with early-stage/favorable Hodgkin's disease is highly effective and without demonstrable late effects. These results indicate that pediatric patients with stages I and II favorable Hodgkin's disease can be cured with limited therapy that does not include an alkylating agent, bleomycin, etoposide, or high-dose, extended-field radiation therapy.

Treatment of unfavorable childhood Hodgkin's disease with VEPA and low-dose, involved-field radiation

PURPOSE

Between January 1990 and April 1993, 56 pediatric patients with Hodgkin's disease were treated on a single-arm trial at three institutions with a regimen designed to maintain high cure rates while minimizing the potential late effects of treatment, such as infertility, second malignant neoplasms, and cardiopulmonary injury.

PATIENTS AND METHODS

The regimen used combined-modality therapy with six cycles of vinblastine, etoposide, prednisone, and doxorubicin (VEPA) chemotherapy and low-dose, involved-field radiation. Unfavorable features comprised bulky presentations of localized (stage I or II) disease or advanced (stage III or IV) Hodgkin's disease.

RESULTS

Of 56 patients enrolled, 26 (46%) had unfavorable presentations of stage I/II disease and 30 (54%) had advanced (stage III/IV) disease. Seventy-nine percent of the patients are alive without disease at a median follow-up time of 8.9 years from diagnosis. Nineteen patients had events at a median of 1.5 years (range, 0.4 to 7.9 years) from diagnosis; 17 patients relapsed, one died of cardiomyopathy, and one died of accidental injuries. Survival and event-free survival (EFS) estimates at 5 years for the entire cohort were 81.9% (SE, 5.2%) and 67.8% (SE, 6.3%), respectively. Five-year EFS by stage was 100% for stage I, 79.2% (SE, 8.3%) for stage II, 70% (SE, 14.5%) for stage III, and 49.5% (SE, 11.3%) for stage IV patients.

CONCLUSION

Combined-modality therapy with VEPA chemotherapy and low-dose, involved-field radiation is adequate for disease control of early-stage patients with unfavorable features, but it is inferior to other standard regimens for advanced-stage patients.

Atypical teratoid/rhabdoid tumor of the central nervous system: report on workshop

Childhood atypical teratoid/rhabdoid tumor (AT/RT) of the central nervous system (CNS) is a recently described entity. Diagnosis is based on distinctive light microscopy and immunohistochemical findings, coupled with molecular genetic analysis. Most AT/RTs demonstrate monosomy 22 or deletions of chromosome band 22q11 with alterations of the hSNF5/INI1 gene. The tumor's incidence is still undefined, but it may comprise as high as 1 in 4 primitive CNS tumors in infants. Treatment is far from optimal, but there are occasional long-term survivors, especially among older children. Therapeutic approached have included surgery, chemotherapy, and radiotherapy. Prospective clinical trials are needed for children with AT/RTs.

Emergency re-operation for postoperative hemorrhage following partial esophagectomy for carcinoma of the esophagus and cardia of the stomach

The clinical records of 12 cases of emergency re-operation for management of postoperative hemorrhage (POH) following partial esophagectomy and esophago-gastrostomy or colonic interposition for a group of 3690 cases of carcinoma of the esophagus (CE) and cardia of the stomach in this institute between August 1954 and April 2001 were studied. There were 10 survivors and two deaths, giving a mortality rate of 16.6% (2/12). It was concluded that an emergency re-operation was a cardinal surgical procedure to save the patient's life if a serious POH had developed. The POH could be prevented by a careful, conscientious and strict hemostasis during the primary operation. The criteria for the diagnosis are presented.

Pleomorphic xanthoastrocytoma: favorable outcome after complete surgical resection

To describe the clinical features, histologic characteristics, and management of patients with pleomorphic xanthoastrocytoma (PXA), we reviewed data on 13 children who had histologically confirmed PXA and were referred to the neuro-oncology service between 1985 and 1999. Neuro-imaging with CT and/or MRI documented the anatomic location, tumor extent, and degree of resection. There were 3 males and 10 females; median age was 12.9 years (range, 8.2-17.2 years). The most frequent presentations included seizures (n = 8) and headache (n = 5). Tumor sites included temporal (n = 5), parietal (n = 3), frontal (n = 1), frontoparietal (n = 1), parietooccipital (n = 1), and temporoparietal (n = 1) lobes and the spinal cord (n = 1). CT/MRI revealed a cystic component in 6 patients, with cyst wall enhancement in 3 patients. The solid component was uniformly enhancing in 11 patients. Vasogenic edema was present in 9 patients, and calcification was noted in 4 patients. Histopathologic findings included meningeal invasion in 12 patients, calcifications in 4, and necrosis in 2. Mitotic figures (1-12 per high-power field) were seen in 8 patients. Gross total resection was achieved in 8 patients, near total resection in 1, and subtotal resection in 4. Ten patients were alive with a median follow-up of 41 months at this writing. Two patients died of progressive disease, and 1 died of an unrelated cause. In conclusion, pleomorphic xanthoastrocytoma is a rare neoplasm in childhood, commonly presenting with seizures. Gross total resection without adjuvant therapy provides prolonged disease control, as seen in 6 of 7 patients (85%) in our series.

Paclitaxel for the treatment of progressive or recurrent childhood brain tumors: a pediatric oncology phase II study

PURPOSE

To assess the efficacy and define the toxicity of paclitaxel given at a dosage of 350 mg/m2 every 3 weeks as a 24-hour continuous infusion to children with recurrent or progressive primary brain tumors.

PATIENTS AND METHODS

Seventy-three eligible patients, ages 4 months to 19 years, with progressive or recurrent primary brain tumors were treated according to a Pediatric Oncology Group (POG) phase II protocol with paclitaxel (POG 9330). Tumor histologic strata included: astrocytoma (n = 4), malignant glioma (n = 13), medulloblastoma (n = 16), brain stem glioma (n = 15), ependymoma (n = 13), and miscellaneous histologies (n = 12). All patients had previous histologic confirmation of a primary intracranial or spinal cord tumor with magnetic resonance imaging or computed tomography documentation of unequivocally measurable progressive or recurrent disease. All patients had received previous therapy including surgery, radiation therapy, and/or chemotherapy, but no patient had been previously treated on more than one phase II trial. Paclitaxel was administered as a 24-hour intravenous infusion at a dosage of 350 mg/m2 every 3 weeks. Neurologic and neuroradiologic reevaluations were performed after every second course. Patients were allowed to continue therapy for a total of 18 cycles in the absence of progressive disease or unacceptable toxicity.

RESULTS

Seventy-five patients were enrolled onto the POG 9330 protocol; two ineligible patients were removed from the study before receiving any therapy. Of the 73 eligible patients, 72 were evaluable for toxicity and 70 were either fully or partially evaluable for disease response. There was one complete response and three partial responses (5.7%). Twenty patients had stable disease for more than 2 months. Toxicities included mild nausea, central nervous system toxicity, myelosuppression, and febrile neutropenia, including one septic death. One grade 2 and two grade 3 allergic reactions occurred. No cardiac toxicities or arthralgias were reported.

CONCLUSION

Paclitaxel is well tolerated in children with recurrent or progressive brain tumors at this dosage and schedule and may result in short-term disease stabilization in this patient population. The lack of a significant number of patients with measurable disease regression, however, precludes it from being identified as an active agent when administered as a single agent by 24-hour continuous infusion.

Patterns of intellectual development among survivors of pediatric medulloblastoma: a longitudinal analysis

PURPOSE

To examine two competing hypotheses relating to intellectual loss among children treated for medulloblastoma (MB): Children with MB either: (1) lose previously learned skills and information; or (2) acquire new skills and information but at a rate slower than expected compared with healthy same-age peers.

PATIENTS AND METHODS

Forty-four pediatric MB patients were evaluated who were treated with postoperative radiation therapy (XRT) with or without chemotherapy. After completion of XRT, a total of 150 examinations were conducted by use of the child version of the Wechsler Intelligence SCALES: These evaluations provided a measure of intellectual functioning called the estimated full-scale intelligence quotient (FSIQ). Changes in patient performance corrected for age (scaled scores) as well as the uncorrected performance (raw scores) were analyzed.

RESULTS

At the time of the most recent examination, the obtained mean estimated FSIQ of 83.57 was more than one SD below expected population norms. A significant decline in cognitive performance during the time since XRT was demonstrated, with a mean loss of 2.55 estimated FSIQ points per year (P =.0001). An analysis for the basis of the intelligence quotient (IQ) loss revealed that subtest raw score values increased significantly over time since XRT, but the rate of increase was less than normally expected, which resulted in decreased IQ scores.

CONCLUSION

These results support the hypothesis that MB patients demonstrate a decline in IQ values because of an inability to acquire new skills and information at a rate comparable to their healthy same-age peers, as opposed to a loss of previously acquired information and skills.

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

PURPOSE

Progress has been made in the treatment of medulloblastoma, the most common childhood malignant brain tumor: However, many long-term survivors will have posttherapy growth hormone insufficiency with resultant linear growth retardation. Growth hormone replacement therapy (GHRT) may significantly improve growth, but there is often reluctance to initiate GHRT because of concerns of an increased likelihood of tumor relapse.

PATIENTS AND METHODS

This study retrospectively reviewed the use of GHRT for survivors of medulloblastoma in 11 neuro-oncology centers in North America who received initial treatment for disease between 1980 and 1993 to determine its impact on disease control. A Landmark analysis was used to evaluate the relative risk of relapse in surviving patients.

RESULTS

Five hundred forty-five consecutive patients less than 15 years of age at diagnosis were identified. Six-year progression-free survival (mean +/- SD) was 40% +/- 5% in children less than 3 years of age at diagnosis compared with 59% +/- 3% for older patients. Older patients with total or near-total resections (P = .003) and localized disease at diagnosis (P < .0001) had the highest likelihood of survival. One hundred seventy patients (33% +/- 3% of the cohort) received GHRT. GHRT use varied widely among institutions, ranging from 5% to 73%. GHRT was begun a mean of 3.9 years after diagnosis, later in children younger than 3 years at diagnosis (5.4 years). By Landmark analyses, for those surviving 2, 3, and 5 years after diagnosis, there was no evidence that GHRT increased the rate of disease relapse.

CONCLUSION

This large retrospective review demonstrates that GHRT is underutilized in survivors of medulloblastoma and is used relatively late in the course of the illness. GHRT is not associated with an increased likelihood of disease relapse.