Melanoma in congenital melanocytic naevi

Congenital melanocytic naevi (CMN) are a known risk factor for melanoma, with the greatest risk currently thought to be in childhood. There has been controversy over the years about the incidence of melanoma, and therefore over the clinical management of CMN, due partly to the difficulties of histological diagnosis and partly to publishing bias towards cases of malignancy. Large cohort studies have demonstrated that melanoma risk in childhood is related to the severity of the congenital phenotype. New understanding of the genetics of CMN offers the possibility of improvement in diagnosis of melanoma, identification of those at highest risk, and new treatment options. We review the world literature and our centre's experience over the last 25 years, including the molecular characteristics of melanoma in these patients and new melanoma incidence and outcome data from our prospective cohort. Management strategies are proposed for presentation of suspected melanoma of the skin and the central nervous system in patients with CMN, including use of oral mitogen-activated protein kinase kinase inhibitors in NRAS-mutated tumours.

Safety and pharmacokinetics of temozolomide using a dose-escalation, metronomic schedule in recurrent paediatric brain tumours

The aims of this study were to determine the maximum tolerated dose (MTD), toxicity and pharmacokinetics of oral temozolomide administered over 42 d in children with recurrent/refractory brain tumours. Cohorts of 3-6 patients were treated for 42 d, followed by a 7-d rest period for a maximum of 6 cycles. Patients were stratified as heavily pre-treated (HPT) and non-heavily pre-treated (NHPT). Starting doses were 50 mg/m2 (HPT) or 75 mg/m2 (NHPT). Out of 28 patients enrolled, 20 were evaluable for toxicity and 19 for pharmacokinetics. Three patients in the NHPT group developed grade 3/4 haematological toxicity, 2 experienced dose-limiting toxicity (thrombocytopenia) at 100 mg/m2, and 9/20 developed grade 3 lymphopenia. MTD in both strata was 85 mg/m2. Responses were observed in 4 patients: 2 complete responses (CR) in medulloblastoma and supratentorial primitive neuroectodermal tumours (PNET), and 2 partial responses (PR) in high-grade glioma, respectively. Overall cumulative exposure was at least 1.5 times higher than in the 5-d administration schedule. In conclusion, the recommended dose of temozolomide is 85 mg/m2 x 42 d. Dose-limiting toxicities are thrombocytopenia and lymphopenia. The observed response rate warrants phase II studies.

Diffuse intrinsic pontine glioma treated with prolonged temozolomide and radiotherapy--results of a United Kingdom phase II trial (CNS 2007 04)

Diffuse intrinsic pontine glioma (DIPG) has a dismal prognosis with no chemotherapy regimen so far resulting in any significant improvement over standard radiotherapy. In this trial, a prolonged regimen (21/28d) of temozolomide was studied with the aim of overcoming O(6)-methylguanine methyltransferase (MGMT) mediated resistance. Forty-three patients with a defined clinico-radiological diagnosis of DIPG received radiotherapy and concomitant temozolomide (75 mg/m(2)) after which up to 12 courses of 21d of adjuvant temozolomide (75-100mg/m(2)) were given 4 weekly. The trial used a 2-stage design and passed interim analysis. At diagnosis median age was 8 years (2-20 years), 81% had cranial nerve abnormalities, 76% ataxia and 57% long tract signs. Median Karnofsky/Lansky score was 80 (10-100). Patients received a median of three courses of adjuvant temozolomide, five received all 12 courses and seven did not start adjuvant treatment. Three patients were withdrawn from study treatment due to haematological toxicity and 10 had a dose reduction. No other significant toxicity related to temozolomide was noted. Overall survival (OS) (95% confidence interval (CI)) was 56% (40%, 69%) at 9 months, 35% (21%, 49%) at 1 year and 17% (7%, 30%) at 2 years. Median survival was 9.5 months (range 7.5-11.4 months). There were five 2-year survivors with a median age of 13.6 years at diagnosis. This trial demonstrated no survival benefit of the addition of dose dense temozolomide, to standard radiotherapy in children with classical DIPG. However, a subgroup of adolescent DIPG patients did have a prolonged survival, which needs further exploration.

Response Assessment in Pediatric Neuro-Oncology: Implementation and Expansion of the RANO Criteria in a Randomized Phase II Trial of Pediatric Patients with Newly Diagnosed High-Grade Gliomas

Determination of tumor response to treatment in neuro-oncology is challenging, particularly when antiangiogenic agents are considered. Nontumoral factors (eg, blood-brain barrier disruption, edema, and necrosis) can alter contrast enhancement independent of true tumor response/progression. Furthermore, gliomas are often infiltrative, with nonenhancing components. In adults, the Response Assessment in Neuro-Oncology (RANO) criteria attempted to address these issues. No such guidelines exist yet for children. The ongoing randomized phase II trial, A Study of Avastin (bevacizumab) in Combination With Temolozomide (TMZ) and Radiotherapy in Paediatric and Adolescent Patients With High-Grade Glioma (HERBY), will establish the efficacy and safety of the antiangiogenic agent bevacizumab for the first-line treatment of newly diagnosed high-grade glioma in children (n = 121 patients, enrollment complete). The primary end point is event-free survival (tumor progression/recurrence by central review, second primary malignancy, or death). Determination of progression or response is based on predefined clinical and radiographic criteria, modeled on the RANO criteria and supported by expert pseudoprogression review and the use of standardized imaging protocols. The HERBY trial will also compare conventional MR imaging (T1-weighted and T2/fluid-attenuated inversion recovery sequences) with conventional MR imaging plus diffusion/perfusion imaging for response assessment. It is anticipated that HERBY will provide new insights into antiangiogenic-treated pediatric brain tumors. HERBY will also investigate the practicality of obtaining adequate quality diffusion/perfusion scans in a trial setting, and the feasibility of implementing standard imaging protocols across multiple sites. To date, 61/73 (83.6%) patients with available data have completed diffusion-weighted imaging (uptake of other nonconventional techniques has been limited). Harmonization of imaging protocols and techniques may improve the robustness of pediatric neuro-oncology studies and aid future trial comparability.

A phase I/II trial of AT9283, a selective inhibitor of aurora kinase in children with relapsed or refractory acute leukemia: challenges to run early phase clinical trials for children with leukemia

Aurora kinases regulate mitosis and are commonly overexpressed in leukemia. This phase I/IIa study of AT9283, a multikinase inhibitor, was designed to identify maximal tolerated doses, safety, pharmacokinetics, and pharmacodynamic activity in children with relapsed/refractory acute leukemia. The trial suffered from poor recruitment and terminated early, therefore failing to identify its primary endpoints. AT9283 caused tolerable toxicity, but failed to show clinical responses. Future trials should be based on robust preclinical data that provide an indication of which patients may benefit from the experimental agent, and recruitment should be improved through international collaborations and early combination with established treatment strategies.

A Diagnostic Algorithm for Posterior Fossa Tumors in Children: A Validation Study

BACKGROUND AND PURPOSE

Primary posterior fossa tumors comprise a large group of neoplasias with variable aggressiveness and short and long-term outcomes. This study aimed to validate the clinical usefulness of a radiologic decision flow chart based on previously published neuroradiologic knowledge for the diagnosis of posterior fossa tumors in children.

MATERIALS AND METHODS

A retrospective study was conducted (from January 2013 to October 2019) at 2 pediatric referral centers, Children's Hospital of Philadelphia, United States, and Great Ormond Street Hospital, United Kingdom. Inclusion criteria were younger than 18 years of age and histologically and molecularly confirmed posterior fossa tumors. Subjects with no available preoperative MR imaging and tumors located primarily in the brain stem were excluded. Imaging characteristics of the tumors were evaluated following a predesigned, step-by-step flow chart. Agreement between readers was tested with the Cohen κ, and each diagnosis was analyzed for accuracy.

RESULTS

A total of 148 cases were included, with a median age of 3.4 years (interquartile range, 2.1-6.1 years), and a male/female ratio of 1.24. The predesigned flow chart facilitated identification of pilocytic astrocytoma, ependymoma, and medulloblastoma sonic hedgehog tumors with high sensitivity and specificity. On the basis of the results, the flow chart was adjusted so that it would also be able to better discriminate atypical teratoid/rhabdoid tumors and medulloblastoma groups 3 or 4 (sensitivity = 75%-79%; specificity = 92%-99%). Moreover, our adjusted flow chart was useful in ruling out ependymoma, pilocytic astrocytomas, and medulloblastoma sonic hedgehog tumors.

CONCLUSIONS

The modified flow chart offers a structured tool to aid in the adjunct diagnosis of pediatric posterior fossa tumors. Our results also establish a useful starting point for prospective clinical studies and for the development of automated algorithms, which may provide precise and adequate diagnostic tools for these tumors in clinical practice.

Visual outcomes and predictors in optic pathway glioma: a single centre study

BACKGROUND/AIMS

Optic pathway gliomas (OPGs) may cause progressive visual loss despite chemotherapy. Newer, less toxic treatments might be given earlier, depending on visual prognosis. We aimed to investigate the prognostic value of visual evoked potentials (VEP) and optical coherence tomography (OCT).

METHODS

A retrospective study of OPG patients (treated 2003-2017) was conducted. Primary outcome was PEDIG category visual acuity in better and worse eyes (good < = 0.2, moderate 0.3-0.6 and poor > = 0.7 logMAR). Binary logistic regression analysis was used to identify predictors of these outcomes.

RESULTS

60 patients (32 Neurofibromatosis type 1 [NF1] and 28 sporadic) had median presentation age 49 months (range 17-183) (NF1) and 27 months (range 4-92) (sporadic). Median follow up was 82 months (range 12-189 months). At follow up 24/32 (75%) of NF1 children and 14/28 (50%) of sporadic children had good better eye visual acuity and 11/32 (34%) of NF1 children and 15/28 (54%) of sporadics had poor worse eye acuity. Mean peripapillary retinal nerve fibre layer (RNFL) thickness predicted good better eye final acuity (OR 0.799, 95%CI 0.646-0.987, p = 0.038). Presenting with visual symptoms (OR 0.22 95% CI 0.001-0.508, p = 0.017) and poorer VEP scores (OR 2.35 95% CI 1.1-5.03, p = 0.027) predicted poor worse eye final acuity. 16 children had homonymous hemianopias at follow up, predicted by poor presenting binocular VEP score (OR 1.449 95%CI 1.052-1.995, p = 0.02).

CONCLUSIONS

We found that both RNFL thickness on OCT and VEP were useful in predicting future visual acuity and vision and potentially in planning treatment. We had a high prevalence of homonymous hemianopia.

Central nervous system tumours in adolescents

Adolescents with brain tumours have been, and in most cases still are, haphazardly assigned, on referral, to either 'paediatric' or 'adult'-based treatment centres. In this age group, there is therefore a history of inconsistent treatment, delivery of inappropriate 'maturity-related' care and a reduced chance of gathering vital biological, clinical and treatment-related information germane to this group of patients and their tumours. These days, adolescents with brain tumours should be actively targeted for recruitment into clinical trials and admission into dedicated neuro-oncology centres or programmes that can deliver the necessary and age appropriate multidisciplinary management.

[Analysis of paediatric neuro-oncological information on the Internet in German language]

BACKGROUND

The fast growing internet offers easy access to medical information. So far there are limited data concerning the quality of this information. This study examined quality and readability of paediatric neuro-oncological information on the internet in german language.

METHOD

Using the search terms "medulloblastoma", "ependymoma", "craniopharyngeoma", "brainstem glioma" and "low grade astrocytoma" in six different search engines, the first 30 universal/uniform resource locators (URLs) of each search engine were assessed. Appropriate Web sites were evaluated in regards to quality using DISCERN-Instrument and checklist rating system. Readability was rated by Flesch Reading Ease score.

RESULTS

Out of 889,56 web sites remained evaluable. Most of the sites rated as poor to very poor (49 %), 30 % rated as fair and 21 % as good to very good. Readability was scored as very difficult with complex vocabulary content limiting the usefulness of good web sites.

CONCLUSIONS

Search-ing for childhood brain tumours via internet is time consuming and most often ineffective. There is a lack of high-quality and comprehensible information on childhood brain tumours on german web sites. Cooperation of scientific medical societies and the Federal Ministry of Health is essential to provide comprehensible and high-quality information on internet as an effective and supportive resource for patients and their relatives.

ITCC phase I study of erlotinib as single agent in children with refractory and relapsed malignant brain tumors and in combination with irradiation in newly diagnosed brain stem glioma

9556

Background: Erlotinib hydrochloride (OSI-774), a selective inhibitor of the EGFR tyrosine kinase, may be active in childhood brain tumors, particularly in combination with irradiation. Methods: Multicenter, non-randomized phase I study with separate dose findings for erlotinib as single agent in children with refractory or relapsing brain tumors (group 1), and combined to irradiation in newly diagnosed brain stem glioma (group 2). Erlotinib was administered orally daily at 75, 100, 125 or 150 mg/m2. Dose escalation was performed in a classical 3+3 methodology for group 1 and according to the continuous reassessment method for group 2; dose-limiting toxicity (DLT) was evaluated at 3 and 6 weeks, respectively. Results: In total, 31 patients have been entered to date, 30 received treatment, 17 in group 1 (3 relapsing brain stem glioma, 4 ependymoma, 4 oligodendroglioma, 6 other) and 13 in group 2 with a median age of 9 and 6 years (range 4–16 and 2–12), respectively. Median treatment duration was 1.5 and >5 months, respectively. In group 1, 3 patients each were treated at 75 mg/m2 and 100 mg/m2, 7 at 125 mg/m2, 4 at 150 mg/m2. One patient with a glioneuronal tumor treated at 125 mg/m2 experienced G5 intra-tumoral hemorrhage at day 4 which was considered as DLT; at 150 mg/m2, 1 patient with an oligodendroglioma experienced G3 asthenia at day 18 and G3 intratumoral hemorrhage at day 29, and 1 patient with an ependymoma experienced G5 intra-tumoral hemorrhage at day 49. In group 2, 1/6 patients treated with erlotinib 75 mg/m2 and irradiation experienced seizures and died, no DLT occurred in 6 patients at 100 mg/m2. Non-hematological toxicities included G1-G2 erythema, folliculitis, dry skin, trichomegaly, G1 transaminitis, bilirubinemia, G1–3 asthenia, G1–5 intra-tumoral hemorrhage. Minor tumor response was observed in an oligodendroglioma. Pharmacokinetic and biological evaluations are ongoing. Conclusions: Erlotinib was well tolerated in children with cutaneous symptoms being the most frequent treatment toxicity. However, neurological toxicity and intra-tumoral hemorrhage was notable in these children with brain tumors. Inclusion at 125 mg/m2 is ongoing to confirm the MTD.

No significant financial relationships to disclose.

Evaluation of the Implementation of the Response Assessment in Neuro-Oncology Criteria in the HERBY Trial of Pediatric Patients with Newly Diagnosed High-Grade Gliomas

BACKGROUND AND PURPOSE

HERBY was a Phase II multicenter trial setup to establish the efficacy and safety of adding bevacizumab to radiation therapy and temozolomide in pediatric patients with newly diagnosed non-brain stem high-grade gliomas. This study evaluates the implementation of the radiologic aspects of HERBY.

MATERIALS AND METHODS

We analyzed multimodal imaging compliance rates and scan quality for participating sites, adjudication rates and reading times for the central review process, the influence of different Response Assessment in Neuro-Oncology criteria in the final response, the incidence of pseudoprogression, and the benefit of incorporating multimodal imaging into the decision process.

RESULTS

Multimodal imaging compliance rates were the following: diffusion, 82%; perfusion, 60%; and spectroscopy, 48%. Neuroradiologists' responses differed for 50% of scans, requiring adjudication, with a total average reading time per patient of approximately 3 hours. Pseudoprogression occurred in 10/116 (9%) cases, 8 in the radiation therapy/temozolomide arm and 2 in the bevacizumab arm (P < .01). Increased target enhancing lesion diameter was a reason for progression in 8/86 cases (9.3%) but never the only radiologic or clinical reason. Event-free survival was predicted earlier in 5/86 (5.8%) patients by multimodal imaging (diffusion, n = 4; perfusion, n = 1).

CONCLUSIONS

The addition of multimodal imaging to the response criteria modified the assessment in a small number of cases, determining progression earlier than structural imaging alone. Increased target lesion diameter, accounting for a large proportion of reading time, was never the only reason to designate disease progression.

Convection-Enhanced Delivery in Children: Techniques and Applications

Since its first description in 1994, convection-enhanced delivery (CED) has become a reliable method of administering drugs directly into the brain parenchyma. More predictable and effective than simple diffusion, CED bypasses the challenging boundary of the blood brain barrier, which has frustrated many attempts at delivering large molecules or polymers into the brain parenchyma. Although most of the clinical work with CED has been carried out on adults with incurable neoplasms, principally glioblastoma multiforme, an increasing number of studies have recognized its potential for paediatric applications, which now include treatment of currently incurable brain tumours such as diffuse intrinsic pontine glioma (DIPG), as well as metabolic and neurotransmitter diseases. The roadmap for the development of hardware and use of pharmacological agents in CED has been well-established, and some neurosurgical centres throughout the world have successfully undertaken clinical trials, admittedly mostly early phase, on the basis of in vitro, small animal and large animal pre-clinical foundations. However, the clinical efficacy of CED, although theoretically logical, has yet to be unequivocally demonstrated in a clinical trial; this applies particularly to neuro-oncology.This review aims to provide a broad description of the current knowledge of CED as applied to children. It reviews published studies of paediatric CED in the context of its wider history and developments and underlines the challenges related to the development of hardware, the selection of pharmacological agents, and gene therapy. It also reviews the difficulties related to the development of clinical trials involving CED and looks towards its potential disease-modifying opportunities in the future.

Pharmacokinetic and biological study of erlotinib in children as monotherapy for refractory brain tumors or with radiation for newly diagnosed brain stem gliomas

10019

Background: This multicenter phase I study was designed to determine the recommended dose (RD) of erlotinib, a small-molecule EGFR TKI, in patients ≤ 21 years as monotherapy or in combination with radiation therapy (RT). Methods: Group 1 included patients with brain tumors refractory to or relapsing after conventional therapy; receiving erlotinib alone. Group 2 included newly diagnosed patients with brain stem gliomas, who received RT (54Gy) and erlotinib. Conventional 3+3 dose escalation was used for Group 1; a continual reassessment method for Group 2. Four dose levels were planned: 75, 100, 125 and 150 mg/m2/day. Results: A total of 51 patients were enrolled (30 in Group 1; 21 in Group 2); 50 received treatment. Median age was 10 and 6 years, respectively. The RD of erlotinib was 125 mg/m2/day as monotherapy or in combination with RT. 203 adverse events in 44 patients were possibly treatment-related; 188 were G1/2; 9 G3, 2 G4, and 4 G5. Dermatologic and neurologic symptoms were most common; intratumoral hemorrhage was noted in 4 patients. In Group 1, 8 patients (27.6%) had stable disease, 2 with 45% tumor regression. In Group 2, 3 patients (14%) had partial response and 8 (38%) were stabilized; median OS was 12 months. Pharmacokinetic data of 46 patients were analyzed; patients’ weight and erlotinib clearance (CL) were significantly correlated. Mean (± SD) apparent CL and volume of distribution for erlotinib were 143.7 mL/h/kg (± 66.3) and 3.5 L/kg (± 3.0), respectively, and were independent of dose level. Mean half-life for erlotinib was 20.4 hours. Biomarker analyses on archived tumor or biopsy tissue prior to study entry for newly diagnosed brain stem glioma found 18/37 tumors tested were EGFR IHC+; 16/37 and 23/36 were pAKT+ and pMAPK+, respectively. High EGFR expression was more common in supratentorial gliomas; PTEN loss was most common in brain stem glioma (15/19) and was not observed in ependymomas. Conclusions: Erlotinib 125 mg/m2/day has an acceptable tolerability profile in pediatric patients with brain tumors, and can be safely combined with RT. Further studies are required to define the efficacy of this treatment approach and to establish the impact of biomarkers on outcomes in pediatric glial tumors.

No significant financial relationships to disclose.