PARC: a phase I/II study evaluating the safety and activity of pegylated recombinant human arginase BCT-100 in relapsed/refractory cancers of children and young adults

Background

The survival for many children with relapsed/refractory cancers remains poor despite advances in therapies. Arginine metabolism plays a key role in the pathophysiology of a number of pediatric cancers. We report the first in child study of a recombinant human arginase, BCT-100, in children with relapsed/refractory hematological, solid or CNS cancers.

Procedure

PARC was a single arm, Phase I/II, international, open label study. BCT-100 was given intravenously over one hour at weekly intervals. The Phase I section utilized a modified 3 + 3 design where escalation/de-escalation was based on both the safety profile and the complete depletion of arginine (defined as adequate arginine depletion; AAD <8μM arginine in the blood after 4 doses of BCT-100). The Phase II section was designed to further evaluate the clinical activity of BCT-100 at the pediatric RP2D determined in the Phase I section, by recruitment of patients with pediatric cancers into 4 individual groups. A primary evaluation of response was conducted at eight weeks with patients continuing to receive treatment until disease progression or unacceptable toxicity.

Results

49 children were recruited globally. The Phase I cohort of the trial established the Recommended Phase II Dose of 1600U/kg iv weekly in children, matching that of adults. BCT-100 was very well tolerated. No responses defined as a CR, CRi or PR were seen in any cohort within the defined 8 week primary evaluation period. However a number of these relapsed/refractory patients experienced prolonged radiological SD.

Conclusion

Arginine depletion is a clinically safe and achievable strategy in children with cancer. The RP2D of BCT-100 in children with relapsed/refractory cancers is established at 1600U/kg intravenously weekly and can lead to sustained disease stability in this hard to treat population.

Clinical trial registration

EudraCT, 2017-002762-44; ISRCTN, 21727048; and ClinicalTrials.gov, NCT03455140.

Bevacizumab, Irinotecan, or Topotecan Added to Temozolomide for Children With Relapsed and Refractory Neuroblastoma: Results of the ITCC-SIOPEN BEACON-Neuroblastoma Trial

PURPOSE

Outcomes for children with relapsed and refractory high-risk neuroblastoma (RR-HRNB) remain dismal. The BEACON Neuroblastoma trial (EudraCT 2012-000072-42) evaluated three backbone chemotherapy regimens and the addition of the antiangiogenic agent bevacizumab (B).

MATERIALS AND METHODS

Patients age 1-21 years with RR-HRNB with adequate organ function and performance status were randomly assigned in a 3 × 2 factorial design to temozolomide (T), irinotecan-temozolomide (IT), or topotecan-temozolomide (TTo) with or without B. The primary end point was best overall response (complete or partial) rate (ORR) during the first six courses, by RECIST or International Neuroblastoma Response Criteria for patients with measurable or evaluable disease, respectively. Safety, progression-free survival (PFS), and overall survival (OS) time were secondary end points.

RESULTS

One hundred sixty patients with RR-HRNB were included. For B random assignment (n = 160), the ORR was 26% (95% CI, 17 to 37) with B and 18% (95% CI, 10 to 28) without B (risk ratio [RR], 1.52 [95% CI, 0.83 to 2.77]; P = .17). Adjusted hazard ratio for PFS and OS were 0.89 (95% CI, 0.63 to 1.27) and 1.01 (95% CI, 0.70 to 1.45), respectively. For irinotecan ([I]; n = 121) and topotecan (n = 60) random assignments, RRs for ORR were 0.94 and 1.22, respectively. A potential interaction between I and B was identified. For patients in the bevacizumab-irinotecan-temozolomide (BIT) arm, the ORR was 23% (95% CI, 10 to 42), and the 1-year PFS estimate was 0.67 (95% CI, 0.47 to 0.80).

CONCLUSION

The addition of B met protocol-defined success criteria for ORR and appeared to improve PFS. Within this phase II trial, BIT showed signals of antitumor activity with acceptable tolerability. Future trials will confirm these results in the chemoimmunotherapy era.

Regorafenib plus Vincristine and Irinotecan in Pediatric Patients with Recurrent/Refractory Solid Tumors: An Innovative Therapy for Children with Cancer Study

PURPOSE

This phase Ib study defined the safety, MTD, and recommended phase II dose (RP2D) of regorafenib combined with vincristine and irinotecan (VI). Secondary objectives were evaluation of antitumor activity and pharmacokinetics (PK) of regorafenib and irinotecan.

PATIENTS AND METHODS

Patients aged 6 months to <18 years with relapsed/refractory solid malignancies [≥50% with rhabdomyosarcoma (RMS)] received regorafenib (starting dose 72 mg/m2/day) concomitantly or sequentially with vincristine 1.5 mg/m2 on days 1 and 8, and irinotecan 50 mg/m2 on days 1-5 (21-day cycle). Adverse events (AE) and tumor response were assessed. PK (regorafenib and irinotecan) were evaluated using a population PK model.

RESULTS

We enrolled 21 patients [median age, 10 years; 12, RMS; 5, Ewing sarcoma (EWS)]. The MTD/RP2D of regorafenib in the sequential schedule was 82 mg/m2. The concomitant dosing schedule was discontinued because of dose-limiting toxicities in 2 of 2 patients treated. Most common grade 3/4 (>30% of patients) AEs were neutropenia, anemia, thrombocytopenia, and leukopenia. The overall response rate was 48% and disease control rate [complete response (CR)/partial response/stable disease/non-CR/non-progressive disease] was 86%. Median progression-free survival was 7.0 months [95% confidence interval (CI), 2.9-14.8] and median overall survival was 8.7 months (95% CI, 5.5-16.3). When combined with VI, regorafenib PK was similar to single-agent PK in children and adults (treated with regorafenib 160 mg/day).

CONCLUSIONS

Regorafenib can be combined sequentially with standard dose VI in pediatric patients with relapsed/refractory solid tumors with appropriate dose modifications. Clinical activity was observed in patients with RMS and EWS (ClinicalTrials.gov NCT02085148).

Generation of evidence-based carboplatin dosing guidelines for neonates and infants

BACKGROUND

To optimally dose childhood cancer patients it is essential that we apply evidence-based dosing approaches. Carboplatin is commonly dosed to achieve a cumulative target exposure (AUC) in children, with target AUC values of 5.2-7.8 mg/ml.min defined. To achieve these exposures patients are dosed at 6.6 mg/kg/day or 4.4 mg/kg for patients <5 kg. The current study uses real world clinical pharmacology data to optimise body weight-based doses to effectively target AUCs of 5.2-7.8 mg/ml.min in infants.

METHODS

Carboplatin exposures were determined across 165 treatment cycles in 82 patients ≤10 kg. AUC and clearance values were determined by Bayesian modelling from samples collected on day 1. These parameters were utilised to assess current dosing variability, determine doses required to achieve target AUC values and predict change in AUC using the modified dose.

RESULTS

No significant differences in clearance were identified between patients <5 kg and 5-10 kg. Consequently, for patients <5 kg, 4.4 mg/kg dosing was not sufficient to achieve a target AUC of 5.2 mg/ml.min, with <55% of patients within 25% of this target. Optimised daily doses for patients ≤10 kg were 6 mg/kg and 9 mg/kg for cumulative carboplatin target exposures of 5.2 and 7.8 mg/ml.min, respectively.

CONCLUSIONS

Adoption of these evidence-based carboplatin doses in neonates and infants will reduce drug exposure variability and positively impact treatment.

Afatinib in paediatric patients with recurrent/refractory ErbB-dysregulated tumours: Results of a phase I/expansion trial

AIM

This phase I/expansion study assessed the safety, pharmacokinetics and preliminary antitumor activity of afatinib in paediatric patients with cancer.

METHODS

The dose-finding part enroled patients (2-<18 years) with recurrent/refractory tumours. Patients received 18 or 23 mg/m2/d afatinib orally (tablet or solution) in 28-d cycles. In the maximum tolerated dose (MTD) expansion, eligible patients (1-<18 years) had tumours fulfilling ≥2 of the following criteria in the pre-screening: EGFR amplification; HER2 amplification; EGFR membrane staining (H-score>150); HER2 membrane staining (H-score>0). The primary end-points were dose-limiting toxicities (DLTs), afatinib exposure, and objective response.

RESULTS

Of 564 patients pre-screened, 536 patients had biomarker data and 63 (12%) fulfilled ≥2 EGFR/HER2 criteria required for inclusion in the expansion part. A total of 56 patients were treated (17 in the dose-finding and 39 in the expansion part). DLTs were observed in one of six MTD-evaluable patients receiving 18 mg/m²/d and in two of five MTD-evaluable patients receiving 23 mg/m²/d; 18 mg/m²/d was defined as the MTD. There were no new safety signals. Pharmacokinetics confirmed exposure consistent with the approved dose in adults. One partial response (-81% per Response Assessment in Neuro-Oncology) was observed in a patient with a glioneuronal tumour harbouring a CLIP2::EGFR fusion; unconfirmed partial responses were observed in two patients. In total, 25% of patients experienced objective response or stable disease (95% confidence interval: 14-38).

CONCLUSION

Targetable EGFR/HER2 drivers are rare in paediatric cancers. Treatment with afatinib led to a durable response (>3 years) in one patient with a glioneuronal tumour with CLIP2::EGFR fusion.

BEACON-Immuno: Results of the dinutuximab beta (dB) randomization of the BEACON-Neuroblastoma phase 2 trial—A European Innovative Therapies for Children with Cancer (ITCC–International Society of Paediatric Oncology Europe Neuroblastoma Group (SIOPEN) trial

10002

Background: The BEACON phase II trial (NCT02308527) addressed a number of questions in children with relapsed/refractory high-risk neuroblastoma (RR-HRNB). Here we report the chemo-immunotherapy randomisation, assessing if anti-GD2 (dB) demonstrates activity when added to chemotherapy. Methods: Patients aged 1-21 years with RR-HRNB with adequate organ function and performance status were randomised in a 1:2 ratio to receive chemotherapy alone or with dB, given concurrently as a 7 day continuous infusion (10 mg/m2/24hr). As the trial had a factorial design, some patients were also randomised between chemotherapy regimens (temozolomide (T) versus Temozolomide-Topotecan (TTo); this randomisation closed soon after the dB randomisation opened and all patients subsequently received TTo chemotherapy. Cross-over to dB with topotecan and cyclophosphamide was allowed for patients randomised to chemotherapy alone who experienced disease progression. The primary outcome measure was best response (complete or partial) at any point during the first 6 courses of treatment, by RECIST or International Neuroblastoma Response Criteria for patients with measurable and evaluable disease respectively. Progression free and overall survival (PFS & OS) and safety were secondary outcomes. The success criterion for proceeding to a Phase 3 trial was a one-sided p-value (1p) less than 0.23 for Objective Response Rate (ORR). Results: From Aug 2019 to Feb 2021, 65 patients were randomised to chemotherapy alone (3 T, 19 TTo) or with dB (6 dBT, 37 dBTTo). Median age was 4 years; 48 and 17 had measurable and evaluable disease respectively; 29 and 36 had refractory and relapsed disease respectively; 19 had MYCN amplification. Baseline characteristics were balanced between arms. Response was assessable in all patients. The ORR was 18% with chemotherapy alone and 35% for patients receiving chemotherapy with dB (risk ratio 1.66, 80% confidence interval (CI) 0.9 to 3.06, 1p = 0.19). 1-year PFS was 27% for chemotherapy alone, and 57% for those receiving chemotherapy +dB (HR 0.63, 95% CI 0.32 to 1.25, p = 0.19). Twelve patients in the chemotherapy only arm crossed over to receive dB at progression. OS did not differ between the arms: HR = 0.99, 95% CI 0.42 to 2.36, p = 0.99. Nine (41%) patients receiving chemotherapy alone and 13 (30%) receiving chemotherapy plus dB had grade ≥3 toxicities (CTCAE v4.0). Neurotoxicities were more common in patients receiving dB compared to chemotherapy alone (Grade 1-2: 67.4% vs 13.6%, Grade 3: 9.3 vs 0%). Other toxicities were similar with and without dB. Conclusions: The Phase 2 success criterion for ORR was met and PFS is also encouraging. The addition of dB to temozolomide-based chemotherapy shows promising activity in patients with RR-HR-NB. Clinical trial information: NCT02308527.

The efficacy of interactive group psychoeducation for children with leukaemia: A randomised controlled trial

OBJECTIVE

To evaluate an interactive group psychoeducation programme for children treated for leukaemia.

METHODS

A longitudinal randomised controlled study across four UK hospitals with an immediate (N = 26) and delay control group (N = 32). The intervention covered the pathophysiology of leukaemia, its treatment, side effects and the importance of positive health behaviours. Primary outcomes were parent-reported child health related quality of life (HRQoL) and behavioural difficulties. Secondary outcomes were child-reported HRQoL, cancer-specific HRQoL, child confidence, caregiver burden, and treatment anxiety. Measures were completed pre- and immediately post-intervention, and at 13 and 26-weeks follow-up. Change over time was analysed using multilevel modelling. Acceptability questionnaires rated the intervention on benefits, recommendations, and barriers to participation.

RESULTS

The intervention significantly improved parent-reported child HRQoL but did not have a significant effect on other outcomes. Acceptability of the intervention was high.

CONCLUSIONS

This study provides initial evidence that interactive group psychoeducation is acceptable to families and improves HRQoL in children with leukaemia. Difficulties with recruitment removed power to detect effect sizes that are plausible for psychoeducational interventions.

PRACTISE IMPLICATIONS

Further studies to explore the potential of psychoeducation to improve outcomes for children with leukaemia and an examination of barriers to participation within this population are warranted.

Vincristine dosing, drug exposure and therapeutic drug monitoring in neonate and infant cancer patients

Background

The anticancer drug vincristine is associated with potentially dose-limiting side-effects, including neurotoxicity and myelosuppression. However, there currently exists a lack of published clinical pharmacology data relating to its use in neonate and infant patients. We report a study investigating vincristine dosing and drug exposure, alongside the feasibility and impact of a therapeutic drug monitoring treatment approach, in this challenging patient population.

Patients and methods

Vincristine pharmacokinetic data from a total of 57 childhood cancer patients, including 26 neonates and infants, were used to characterise a population pharmacokinetic model. Vincristine was administered at doses of 0.02–0.05 mg/kg or 0.75–1.5 mg/m² in neonates and infants aged <1 year or ≤12 kg and doses of 1.5 mg/m² in older children.

Results

A two-compartment model provided the best fit for the population analysis. There was no significant difference in vincristine clearance normalised for body surface area between neonates/infants and older children. Lower doses administered to neonates and infants resulted in significantly lower drug exposures (area under the curve [AUC]), compared with older children (p = 0.047). Vincristine doses of <0.05 mg/kg in neonates and infants resulted in significantly lower AUC values than observed in those receiving doses of ≥0.05 mg/kg (p ≤ 0.0001). Therapeutic drug monitoring was shown to be feasible, effective and well tolerated in neonates and infants experiencing suboptimal drug exposures.

Conclusion

Doses of <0.05 mg/kg should not be used in neonate and infant patients because of a high risk of patients experiencing potentially suboptimal drug exposures. Therapeutic drug monitoring approaches in neonates and infants are supported by the data generated, with a proposed target therapeutic window of 50–100 μg/l∗h.

•

Vincristine dosing and drug exposure was investigated in neonates and infants.

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Vincristine concentrations were quantified in 210 plasma samples from 57 children.

•

Lower drug exposures were observed in infants and neonates compared with older children.

•

Therapeutic drug monitoring can be used to avoid suboptimal vincristine drug exposures.

•

Vincristine dosing guidance is provided for treatment of neonate and infant patients.

Impact of COVID-19 in paediatric early-phase cancer clinical trials in Europe: A report from the Innovative Therapies for Children with Cancer (ITCC) consortium

INTRODUCTION

Data regarding real-world impact on cancer clinical research during COVID-19 are scarce. We analysed the impact of the COVID-19 pandemic on the conduct of paediatric cancer phase I-II trials in Europe through the experience of the Innovative Therapies for Children with Cancer (ITCC).

METHODS

A survey was sent to all ITCC-accredited early-phase clinical trial hospitals including questions about impact on staff activities, recruitment, patient care, supply of investigational products and legal aspects, between 1st March and 30th April 2020.

RESULTS

Thirty-one of 53 hospitals from 12 countries participated. Challenges reported included staff constraints (30% drop), reduction in planned monitoring activity (67% drop of site initiation visits and 64% of monitoring visits) and patient recruitment (61% drop compared with that in 2019). The percentage of phase I, phase II trials and molecular platforms closing to recruitment in at least one site was 48.5%, 61.3% and 64.3%, respectively. In addition, 26% of sites had restrictions on performing trial assessments because of local contingency plans. Almost half of the units suffered impact upon pending contracts. Most hospitals (65%) are planning on improving organisational and structural changes.

CONCLUSION

The study reveals a profound disruption of paediatric cancer early-phase clinical research due to the COVID-19 pandemic across Europe. Reported difficulties affected both patient care and monitoring activity. Efforts should be made to reallocate resources to avoid lost opportunities for patients and to allow the continued advancement of oncology research. Identified adaptations to clinical trial procedures may be integrated to increase preparedness of clinical research to futures crises.

Constitutional de novo deletion CNV encompassing REST predisposes to diffuse hyperplastic perilobar nephroblastomatosis (HPLN)

BACKGROUND

Nephroblastomatosis is a recognised precursor for the development of Wilms tumour (WT), the most common childhood renal tumour. While the majority of WT is sporadic in origin, germline intragenic mutations of predisposition genes such as WT1, REST and TRIM28 have been described in apparently isolated (non-familial) WT.Despite constitutional CNVs being a well-studied cause of developmental disorders, their role in cancer predisposition is less well defined, so that the interpretation of cancer risks associated with specific CNVs can be complex.

OBJECTIVE

To highlight the role of a constitutional deletion CNV (delCNV) encompassing the REST tumour suppressor gene in diffuse hyperplastic perilobar nephroblastomatosis (HPLN).

METHODS/RESULTS

Array comparative genomic hybridisation in an infant presenting with apparently sporadic diffuse HPLN revealed a de novo germline CNV, arr[GRCh37] 4q12(57,385,330-57,947,405)x1. The REST tumour suppressor gene is located at GRCh37 chr4:57,774,042-57,802,010.

CONCLUSION

This delCNV encompassing REST is associated with nephroblastomatosis. Deletion studies should be included in the molecular work-up of inherited predisposition to WT/nephroblastomatosis. Detection of delCNVs involving known cancer predisposition genes can yield insights into the relationship between underlying genomic architecture and associated tumour risk.

Over a decade of experience with carboplatin therapeutic drug monitoring in a childhood cancer setting in the United Kingdom

The widely used platinum agent carboplatin represents a good example of an anticancer drug where clear relationships between pharmacological exposure and clinical response and toxicity have previously been shown. Within the setting of childhood cancer, there are defined groups of patients who present a particular challenge when dosing with carboplatin, including neonates and infants, those who are anephric, and poor prognosis patients receiving high-dose chemotherapy. For these groups, nonstandard chemotherapy dosing regimens are currently utilised, often with different approaches between clinical study protocols and between treatment centres. For the treatment of these patient populations in the UK, there is now significant experience in carrying out therapeutic drug monitoring, aiming to consistently achieve target drug exposures, maximise drug efficacy and minimise treatment-related side effects. An ongoing clinical trial is currently providing information on drug exposure for a wide range of anticancer agents in these hard to treat patient populations. In addition to supporting dosing decisions for individual patients, the collection and analysis of these data may allow the development of future dosing regimens. For example, current reduced dosing approaches for neonates and infants based on age or body weight, may well be better replaced by regimens based on a sound pharmacological rationale. The successful use of adaptive carboplatin dosing in childhood cancer should encourage the development of therapeutic drug monitoring approaches more widely in an oncology setting.

Randomized comparisons of bevacizumab (B) and irinotecan (I), added to temozolomide (T), in children with relapsed or refractory high-risk neuroblastoma (RR-HRNB): First survival results of the ITCC-SIOPEN BEACON-Neuroblastoma phase II trial

10501

Background: BEACON is a randomized phase 2 trial assessing whether inhibiting angiogenesis with bevacizumab adds to the activity of chemotherapy and evaluating chemotherapy regimens for children with RR-HRNB. Methods: Patients with RR-HRNB were eligible. There were randomizations (rand), in a 3x2 factorial design, to: T, IT or topotecan (To)-T, +/- B. Toxicity and response were reported in 2019 (ASCO, ESMO). Survival outcomes – progression-free (PFS) and overall (OS) – for the I and B rands are reported here (To rand is still open). The B rand used a relaxed alpha (1-sided p=0.2) for PFS as its phase 2 success criterion; the I rand was Bayesian. Cox model hazard ratios (HR) <1.0 indicate benefit for I or B. Heterogeneity tests (HT) assessed interactions between B and I. Analysis was intention-to-treat. Results: From 2013-19, 160 patients were randomized to B v. no B, including 121 to I v. no I, with: median age 5.8 years; 113 and 47 measurable and evaluable disease; 67 and 93 refractory and relapsed disease; 35 had MYCN amplification. Median follow-up was 15.4 months. PFS and OS are shown in the table. In the main comparisons (I v. no I, B v. no B), I improved PFS and OS (98% probability that true HR<1.0 for both) and B just met its success criterion (PFS: 1p=0.20; OS: 1p=0.19). However, there was some, but not conclusive, evidence of a positive interaction between B and I for both PFS (HT: p=0.06) and OS (HT: p=0.12). If real, this would suggest that adding either I (IT) or B (BT) to T does not improve outcome, but adding both (BIT) does. Twice as many patients had serious adverse events with BIT (57%) than with T (26%) or IT (27%), with BT at 40%. Conclusions: The BEACON results show that single agent T is suboptimal. Statistical uncertainty about an interaction between I and B means two further interpretations are possible: 1) IT and possibly BT are better than T; 2) IT and BT are not better than T, but I and B together (BIT) are better. Hence, a definitive conclusion on the best combination(s) to take forward is not currently possible and further randomized evaluation is needed. Clinical trial information: ISRCTN40708286. [Table: see text]

Phase I study of regorafenib in combination with vincristine and irinotecan in pediatric patients with recurrent or refractory solid tumors

10507

Background: In pediatric patients with solid tumors, regorafenib demonstrated acceptable tolerability and preliminary anti-tumor activity. This phase 1 study evaluated regorafenib in combination with vincristine/irinotecan in pediatric patients with rhabdomyosarcoma (RMS) and other solid tumors. Methods: Patients with relapsed/refractory tumors received intravenous vincristine (1.5 mg/m2, Days 1 and 8) and irinotecan (50 mg/m2/day, Days 1–5) plus once-daily oral regorafenib (patients 6– < 24 months: 60 mg/m2 escalating to 65 mg/m2; patients 2– < 18 years: 72 mg/m2 escalating to 82 mg/m2) on either Days 1–14 (concomitant dosing) or Days 8–21 (sequential dosing) during each 21-day cycle. As per protocol, at least 50% of patients were required to have RMS. Results: At the time of the cut-off, of 21 treated patients (RMS, n = 12; Ewing sarcoma, n = 5; neuroblastoma, n = 3; Wilms tumor, n = 1), two had concomitant (72 mg/m2) and 19 had sequential (72 mg/m2, n = 6; 82 mg/m2, n = 13) dosing. Median age was 10 years (1.5–17.0). Patients received a median of 3 cycles (1–17); dose reductions of irinotecan occurred in 62% of patients. Grade 3 dose-limiting toxicities were reported in both patients receiving concomitant dosing (peripheral neuropathy and liver injury; pain, vomiting, febrile aplasia) and one patient each in the sequential groups (rash and elevated AST; thrombocytopenia). Concomitant dosing was discontinued. The maximum tolerated dose and recommended phase 2 dose (RP2D) of regorafenib in the sequential combination was 82 mg/m2. The most common grade ≥3 treatment-emergent adverse events were neutropenia (71%), thrombocytopenia (33%), leukopenia (29%), anemia (24%), and ALT increased (24%). The response rate was 38%, including 1 complete (RMS) and 7 partial responders (5 RMS, 2 Ewing sarcoma); 3 of whom had prior irinotecan. Six (4 with alveolar subtype) of 12 patients with RMS had a response. Nine patients (43%) had stable disease (maximum duration 17 cycles). After the cut-off, partial response was reported for two additional patients (1 RMS, 1 Ewing sarcoma). Conclusions: Regorafenib can be combined at its single agent RP2D of 82 mg/m2 with standard-dose vincristine/irinotecan (with appropriate dose modifications) in pediatric patients with refractory/relapsed solid tumors in a sequential dosing schedule. Clinical activity was observed in patients with sarcoma. Clinical trial information: NCT02085148.

Temozolomide versus irinotecan-temozolomide for children with relapsed and refractory high risk neuroblastoma (RR-HRNB): Results of the BEACON-Neuroblastoma randomized phase 2 trial—A European Innovative Therapies for Children with Cancer (ITCC) - International Society of Pediatric Oncology Europe Neuroblastoma Group (SIOPEN) trial

10001

Background: BEACON-Neuroblastoma is a randomized Phase II trial to assess the activity of backbone chemotherapy regimens for children with RR-HRNB and to determine if inhibiting angiogenesis with bevacizumab adds to the activity of this chemotherapy. Methods: Patients aged 1-21 years with RR-HRNB with adequate organ function and performance status were randomized in a 2x2 factorial design to: temozolomide (T) versus irinotecan-temozolomide (IT), with or without bevacizumab. Here we report the results of the irinotecan randomization (T vs. IT), which had a probability-based Bayesian design. Primary endpoint was best overall response (complete or partial) during the first 6 courses, by RECIST for measurable disease patients and International Neuroblastoma Response Criteria for evaluable disease patients for which overall response rate (ORR) was calculated. Results: From 2013 to 2018, 61 patients were randomized to treatment with T and 60 to IT. Median age was 5.8 years. 85 and 36 had measurable and evaluable disease respectively; 55 and 66 had refractory and relapsed disease; 22 had MYCN amplification. Baseline characteristics were balanced between the arms. Response data was not yet available for 2 patients on T. Response was not assessable for 17 patients (did not have treatment or stopped early) who were considered non-responders. The ORR was 24% for T and 17% for IT (risk ratio (RR) = 0.70, 95% credible interval 0.32 to 1.44). The probability that the RR for ORR was >1.0 was 17%, meaning that IT did not show greater activity than T. There was no interaction between treatment with/without bevacizumab (heterogeneity test, p=0.7). 27 (44%) T and 35 (58%) IT patients had grade ≥3 toxicities as per CTCAE v4.0. Diarrhea occurred in no patients on T and 7 (12%) on IT; hematological toxicities included anemia (6 T, 4 IT), neutropenia (14 T, 22 IT) and thrombocytopenia (14 T, 11 IT). Conclusions: Irinotecan does not improve the response rate when added to temozolomide in RR-HRNB, but does increase diarrhea. Longer follow-up is needed before assessing whether it impacts progression-free or overall survival. Number of responses by treatment arm. Clinical trial information: NCT02308527. [Table: see text]

PEPtalk2: results of a pilot randomised controlled trial to compare VZIG and aciclovir as postexposure prophylaxis (PEP) against chickenpox in children with cancer

OBJECTIVE

To determine the likely rate of patient randomisation and to facilitate sample size calculation for a full-scale phase III trial of varicella zoster immunoglobulin (VZIG) and aciclovir as postexposure prophylaxis against chickenpox in children with cancer.

DESIGN

Multicentre pilot randomised controlled trial of VZIG and oral aciclovir.

SETTING

England, UK.

PATIENTS

Children under 16 years of age with a diagnosis of cancer: currently or within 6 months of receiving cancer treatment and with negative varicella zoster virus (VZV) serostatus at diagnosis or within the last 3 months.

INTERVENTIONS

Study participants who have a significant VZV exposure were randomised to receive PEP in the form of VZIG or aciclovir after the exposure.

MAIN OUTCOME MEASURES

Number of patients registered and randomised within 12 months of the trial opening to recruitment and incidence of breakthrough varicella.

RESULTS

The study opened in six sites over a 13-month period. 482 patients were screened for eligibility, 32 patients were registered and 3 patients were randomised following VZV exposure. All three were randomised to receive aciclovir and there were no cases of breakthrough varicella.

CONCLUSIONS

Given the limited recruitment to the PEPtalk2 pilot, it is unlikely that the necessary sample size would be achievable using this strategy in a full-scale trial. The study identified factors that could be used to modify the design of a definitive trial but other options for defining the best means to protect such children against VZV should be explored.

TRIAL REGISTRATION NUMBER

ISRCTN48257441, EudraCT number: 2013-001332-22, sponsor: University of Birmingham.

Topotecan-Vincristine-Doxorubicin in Stage 4 High-Risk Neuroblastoma Patients Failing to Achieve a Complete Metastatic Response to Rapid COJEC: A SIOPEN Study

PURPOSE

Metastatic response to induction therapy for high-risk neuroblastoma is a prognostic factor. In the International Society of Paediatric Oncology Europe Neuroblastoma (SIOPEN) HR-NBL-1 protocol, only patients with metastatic complete response (CR) or partial response (PR) with ≤ three abnormal skeletal areas on iodine 123-metaiodobenzylguanidine ([123I]mIBG) scintigraphy and no bone marrow disease proceed to high dose therapy (HDT). In this study, topotecan-vincristine-doxorubicin (TVD) was evaluated in patients failing to achieve these criteria, with the aim of improving the metastatic response rate.

MATERIALS AND METHODS

Patients with metastatic high-risk neuroblastoma who had not achieved the SIOPEN criteria for HDT after induction received two courses of topotecan 1.5 mg/m2/day for 5 days, followed by a 48-hour infusion of vincristine, 2 mg/m2, and doxorubicin, 45 mg/m2.

RESULTS

Sixty-three patients were eligible and evaluable. Following two courses of TVD, four (6.4%) patients had an overall CR, while 28 (44.4%) had a PR with a combined response rate of 50.8% (95% confidence interval [CI], 37.9 to 63.6). Of these, 23 patients achieved a metastatic CR or a PR with ≤ 3 mIBG skeletal areas and no bone marrow disease (36.5%; 95% CI, 24.7 to 49.6) and were eligible to receive HDT. Toxicity was mostly haematological, affecting 106 of the 126 courses (84.1%; 95% CI, 76.5 to 90.0), and dose reduction was necessary in six patients. Stomatitis was the second most common nonhematological toxicity, occurring in 20 patients (31.7%).

CONCLUSION

TVD was effective in improving the response rate of high-risk neuroblastoma patients after induction with COJEC enabling them to proceed to HDT. However, the long-term benefits of TVD needs to be determined in randomized clinical trials.

A phase I trial of AT9283 (a selective inhibitor of aurora kinases) in children and adolescents with solid tumors: a Cancer Research UK study

PURPOSE

A phase I trial of AT9283 (a multitargeted inhibitor of Aurora kinases A and B) was conducted in children and adolescents with solid tumors, to identify maximum-tolerated dose (MTD), safety, efficacy, pharmacokinetics, and pharmacodynamic (PD) activity.

EXPERIMENTAL DESIGN

AT9283 was administered as a 72-hour continuous intravenous infusion every 3 weeks. A rolling-six design, explored six dose levels (7, 9, 11.5, 14.5, 18.5, and 23 mg/m(2)/d). Pharmacokinetic and PD assessments, included inhibition of phospho-histone 3 (pHH3) in paired skin punch biopsies.

RESULTS

Thirty-three patients were evaluable for toxicity. There were six dose-limiting toxicities and the MTD was 18.5 mg/m(2)/d. Most common drug-related toxicities were hematologic (neutropenia, anemia, and thrombocytopenia in 36.4%, 18.2%, and 21.2% of patients), which were grade ≥3 in 30.3%, 6.1%, and 3% of patients. Nonhematologic toxicities included fatigue, infections, febrile neutropenia and ALT elevation. One patient with central nervous system-primitive neuroectodermal tumor (CNS-PNET) achieved a partial response after 16 cycles and 3 cases were stable for four or more cycles. Plasma concentrations were comparable with those in adults at the same dose level, clearance was similar although half-life was shorter (4.9 ± 1.5 hours, compared with 8.4 ± 3.7 hours in adults). Inhibition of Aurora kinase B was shown by reduction in pHH3 in 17 of 18 patients treated at ≥11.5 mg/m(2)/d.

CONCLUSION

AT9283 was well tolerated in children and adolescents with solid tumors with manageable hematologic toxicity. Target inhibition was demonstrated. Disease stabilization was documented in intracranial and extracranial pediatric solid tumors and a phase II dose determined.

Hypoxia-induced cytotoxic drug resistance in osteosarcoma is independent of HIF-1Alpha

Survival rates from childhood cancer have improved dramatically in the last 40 years, such that over 80% of children are now cured. However in certain subgroups, including metastatic osteosarcoma, survival has remained stubbornly poor, despite dose intensive multi-agent chemotherapy regimens, and new therapeutic approaches are needed. Hypoxia is common in adult solid tumours and is associated with treatment resistance and poorer outcome. Hypoxia induces chemotherapy resistance in paediatric tumours including neuroblastoma, rhabdomyosarcoma and Ewing’s sarcoma, in vitro, and this drug resistance is dependent on the oxygen-regulated transcription factor hypoxia inducible factor-1 (HIF-1). In this study the effects of hypoxia on the response of the osteosarcoma cell lines 791T, HOS and U2OS to the clinically relevant cytotoxics cisplatin, doxorubicin and etoposide were evaluated. Significant hypoxia-induced resistance to all three agents was seen in all three cell lines and hypoxia significantly reduced drug-induced apoptosis. Hypoxia also attenuated drug-induced activation of p53 in the p53 wild-type U2OS osteosarcoma cells. Drug resistance was not induced by HIF-1α stabilisation in normoxia by cobalt chloride nor reversed by the suppression of HIF-1α in hypoxia by shRNAi, siRNA, dominant negative HIF or inhibition with the small molecule NSC-134754, strongly suggesting that hypoxia-induced drug resistance in osteosarcoma cells is independent of HIF-1α. Inhibition of the phosphoinositide 3-kinase (PI3K) pathway using the inhibitor PI-103 did not reverse hypoxia-induced drug resistance, suggesting the hypoxic activation of Akt in osteosarcoma cells does not play a significant role in hypoxia-induced drug resistance. Targeting hypoxia is an exciting prospect to improve current anti-cancer therapy and combat drug resistance. Significant hypoxia-induced drug resistance in osteosarcoma cells highlights the potential importance of hypoxia as a target to reverse drug resistance in paediatric osteosarcoma. The novel finding of HIF-1α independent drug resistance suggests however other hypoxia related targets may be more relevant in paediatric osteosarcoma.

Categorising paediatric prescribing errors by junior doctors through prescribing competency assessment: does assessment reflect actual practice?

PURPOSE

It is recognised that paediatric prescribing errors are prevalent, and that most are made by junior doctors; however, detecting errors in order to demonstrate actual error rates can be difficult. There is evidence to suggest that dosing errors are the most common type of prescribing error in practice, but there has been little research on whether prescribing assessments are an effective reflection of actual practice.This article aims to determine if prescribing error types in a paediatric prescribing competency assessment reflects error types seen in actual practice.

METHODS

This study was conducted in Royal Manchester Children's Hospital (RMCH) and the participants were junior doctors working at RMCH in 2010-2011. The intervention was a prescribing competency assessment package at RMCH.The main outcome measurement was the category and rate of prescribing errors. Results were taken from the junior doctors' prescribing competency assessment. The assessment papers were analysed for errors and the errors were then broken down into pre-defined categories.

RESULTS

Rates of prescribing errors in the competency assessment are higher than published results shown in practice (23.1 %). The most common type of prescribing error (incorrect calculation of dose) reflects results seen in actual practice.

CONCLUSION

The types of prescribing errors made in the competency assessment are reflective of errors made in actual practice. Prescribing teaching can be tailored according to the types of errors noted; and the prescribing competency package as a whole can be used to educate junior doctors on good prescribing practice and reduce prescribing errors.

Alteration of cellular behavior and response to PI3K pathway inhibition by culture in 3D collagen gels

Most investigations into cancer cell drug response are performed with cells cultured on flat (2D) tissue culture plastic. Emerging research has shown that the presence of a three-dimensional (3D) extracellular matrix (ECM) is critical for normal cell behavior including migration, adhesion, signaling, proliferation and apoptosis. In this study we investigate differences between cancer cell signaling in 2D culture and a 3D ECM, employing real-time, live cell tracking to directly observe U2OS human osteosarcoma and MCF7 human breast cancer cells embedded in type 1 collagen gels. The activation of the important PI3K signaling pathway under these different growth conditions is studied, and the response to inhibition of both PI3K and mTOR with PI103 investigated. Cells grown in 3D gels show reduced proliferation and migration as well as reduced PI3K pathway activation when compared to cells grown in 2D. Our results quantitatively demonstrate that a collagen ECM can protect U2OS cells from PI103. Overall, our data suggests that 3D gels may provide a better medium for investigation of anti-cancer drugs than 2D monolayers, therefore allowing better understanding of cellular response and behavior in native like environments.

A phase I trial of AT9283 (a selective inhibitor of Aurora kinases) given for 72 hours every 21 days via intravenous infusion in children and adolescents with relapsed and refractory solid tumours

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Background: AT9283, is a multi-targeted inhibitor, against Aurora A and B, JAK & ABL kinases. Aurora kinases are potential therapeutic targets in paediatric solid cancers. Methods: A phase I dose escalation study was performed using a 72 hour intravenous infusion repeated 3 weekly using a rolling 6 design for patients aged >2 to <19 years with relapsed/ refractory solid tumours. Results: Eighteen patients treated with a median age of 10 (range 3 to 16) years. Four dose cohorts of 7, 9, 11.5 and 14.5 mg/m2/day. The diagnoses included; 5 high grade glioma, 4 rhabdoid tumours, 3 neuroblastomas, 3 sarcomas & 3 others. There has been only one dose limiting toxicity; Grade 3 febrile neutropenia at 11.5 mg/m2/day. The majority of adverse events (AEs) have been grade 1/2 & considered unrelated/ unlikely related to study drug. Two patients have experienced Grade 3 or 4 AEs considered at least possibly related to study drug: Grade 3 haemoglobin and Grade 4 neutrophils in a patient treated at 9 mg/m2/day & Grade 3 lymphopenia, neutrophils, infection with normal neutrophil count and aspartate transaminase in a patient treated at 11.5 mg/m2/day. Pharmacokinetics of AT9283 in this population are largely in keeping with those seen in adult patients at similar doses (Arkenau et al., 2011) although there may be greater variability. Pharmacodynamic evidence of aurora B inhibition, as manifested by a reduction in histone H3 phosphorylation in normal skin biopsies pre & post infusion, has been documented at all dose levels tested. Stable disease (up to 6 cycles) has been observed in 3 patients. Conclusions: This paediatric phase I study has demonstrated AT9283 administered as a 72 hour continuous infusion can be given at a dose level of 11.5 mg/m2/day which is higher than the maximum tolerated dose observed in adult patients (9 mg/m2/day) with advanced solid tumours. Myelosuppresion is the main toxicity but the regimen is well tolerated with preliminary anticancer activity seen in heavily pre-treated paediatric patients. [Table: see text]

The novel Bcl-2 inhibitor ABT-737 is more effective in hypoxia and is able to reverse hypoxia-induced drug resistance in neuroblastoma cells

Neuroblastoma is a common solid tumor of childhood and advanced disease carries a poor prognosis despite intensive multimodality therapy. Hypoxia is a common feature of solid tumors because of poorly organized tumor-induced neovasculature. Hypoxia is associated with advanced stage and poor outcome in a range of tumor types, and leads to resistance to clinically relevant cytotoxic agents in neuroblastoma and other pediatric tumors in vitro. Resistance to apoptosis is a common feature of tumor cells and leads to pleiotropic drug resistance, mediated by Bcl-2 family proteins. ABT-737 is a novel small-molecule inhibitor of Bcl-2 and Bcl-x(L) that is able to induce apoptosis in a range of tumor types. Neuroblastoma cell lines are relatively resistant to ABT-737-induced apoptosis in normoxia, but in contrast to the situation with conventional cytotoxic agents are more sensitive in hypoxia. This sensitization is because of an increase in ABT-737-induced apoptosis and is variably dependent upon the presence of functional hypoxia-inducible factor 1 (HIF-1) α. In contrast to the situation in colon carcinoma and non-small cell lung cancer cells, hypoxia does not result in downregulation of the known ABT-737 resistance factor, Mcl-1, nor any other Bcl-2 family proteins. ABT-737 sensitizes neuroblastoma cells to clinically relevant cytotoxic agents under normal levels of oxygen, and importantly, this sensitization is maintained under hypoxia when neuroblastoma cells are resistant to these agents. Thus rational combinations of ABT-737 and conventional cytotoxics offer a novel approach to overcoming hypoxia-induced drug resistance in neuroblastoma.

Hypoxic human cancer cells are sensitized to BH-3 mimetic–induced apoptosis via downregulation of the Bcl-2 protein Mcl-1

Solid tumors contain hypoxic regions in which cancer cells are often resistant to chemotherapy-induced apoptotic cell death. Therapeutic strategies that specifically target hypoxic cells and promote apoptosis are particularly appealing, as few normal tissues experience hypoxia. We have found that the compound ABT-737, a Bcl-2 homology domain 3 (BH-3) mimetic, promotes apoptotic cell death in human colorectal carcinoma and small cell lung cancer cell lines exposed to hypoxia. This hypoxic induction of apoptosis was mediated through downregulation of myeloid cell leukemia sequence 1 (Mcl-1), a Bcl-2 family protein that serves as a biomarker for ABT-737 resistance. Downregulation of Mcl-1 in hypoxia was independent of hypoxia-inducible factor 1 (HIF-1) activity and was consistent with decreased global protein translation. In addition, ABT-737 induced apoptosis deep within tumor spheroids, consistent with an optimal hypoxic oxygen tension being necessary to promote ABT-737–induced cell death. Tumor xenografts in ABT-737–treated mice also displayed significantly more apoptotic cells within hypoxic regions relative to normoxic regions. Synergies between ABT-737 and other cytotoxic drugs were maintained in hypoxia, suggesting that this drug may be useful in combination with chemotherapeutic agents. Taken together, these findings suggest that Mcl-1–sparing BH-3 mimetics may induce apoptosis in hypoxic tumor cells that are resistant to other chemotherapeutic agents and may have a role in combinatorial chemotherapeutic regimens for treatment of solid tumors.

Bioengineering approaches to study multidrug resistance in tumor cells

The ability of cancer cells to become resistant to chemotherapeutic agents is a major challenge for the treatment of malignant tumors. Several strategies have emerged to attempt to inhibit chemoresistance, but the fact remains that resistance is a problem for every effective anticancer drug. The first part of this review will focus on the mechanisms of chemoresistance. It is important to understand the environmental cues, transport limitations and the cellular signaling pathways associated with chemoresistance before we can hope to effectively combat it. The second part of this review focuses on the work that needs to be done moving forward. Specifically, this section focuses on the necessity of translational research and interdisciplinary directives. It is critical that the expertise of oncologists, biologists, and engineers be brought together to attempt to tackle the problem. This discussion is from an engineering perspective, as the dialogue between engineers and other cancer researchers is the most challenging due to non-overlapping background knowledge. Chemoresistance is a complex and devastating process, meaning that we urgently need sophisticated methods to study the process of how cells become resistant.

A small molecule inhibitor of XIAP induces apoptosis and synergises with vinorelbine and cisplatin in NSCLC

Background:

Evasion of apoptosis contributes to the pathogenesis of solid tumours including non-small cell lung cancer (NSCLC). Malignant cells resist apoptosis through over-expression of inhibitor of apoptosis proteins (IAPs), such as X-linked IAP (XIAP).

Methods:

A phenylurea-based small molecule inhibitor of XIAP, XIAP antagonist compound (XAC) 1396-11, was investigated preclincally to determine its ability to sensitise to clinically relevant cytotoxics, potentially allowing dose reduction while maintaining therapeutic efficacy.

Results:

XIAP protein expression was detected in six NSCLC cell lines examined. The cytotoxicity of XAC 1396-11 against cultured NSCLC cell lines in vitro was concentration- and time-dependent in both short-term and clonogenic assays. XAC 1396-11-induced apoptosis was confirmed by PARP cleavage and characteristic nuclear morphology. XAC 1396-11 synergised with vinorelbine±cisplatin in H460 and A549 NSCLC cells. The mechanism of synergy was enhanced apoptosis, shown by increased cleavage of caspase-3 and PARP and by the reversal of synergy by a pan-caspase inhibitor. Synergy between XAC 1396-11 and vinorelbine was augmented by optimising drug scheduling with superior effects when XAC 1396-11 was administered before vinorelbine.

Conclusion:

These preclinical data suggest that XIAP inhibition in combination with vinorelbine holds potential as a therapeutic strategy in NSCLC.

The incidence of anastomotic leaks in patients undergoing colorectal surgery

BACKGROUND

There is evolving interest in auditing and credentialling the performance of surgeons. The incidence of anastomotic leakage has been proposed as a measure of performance following colorectal surgery. The aim of this study was to evaluate the incidence and risk factors associated with anastomotic leakage in patients undergoing resections of the colon and rectum.

METHODS

A prospective database was developed for all patients undergoing colorectal surgery. Anastomotic leakage was defined prior to the commencement of the study. A logistic regression analysis was performed to determine independent predictors of leakage. The variables analysed included age, sex, American Society of Anesthesiology (ASA) score, anatomical location, pathology, emergency surgery, type of anastomosis, a covering stoma and radiotherapy. Significance was defined as the probability of a type 1 error of < 5%. The results are presented as odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS

There were 1598 patients who underwent 1639 anastomoses. Their mean age was 63 years, 34% of patients were ASA 3 or 4, and 16% of the operations were emergencies. Anastomotic leaks occurred in 2.4% (40/1639) of anastomoses. The leak rate for intraperitoneal anastomoses was 1.5% (19/1283) vs 6.6% for extraperitoneal anastomoses (21/316). Half of these leaks (20/40) were managed with re-operation or percutaneous drainage procedures. Ultra-low anterior resections were associated with the highest leak rate (8%, 18/225). A logistic regression analysis identified a covering stoma (P = 0.0001, OR 5.078, 95% CI 2.527-10.23) and diverticular disease (P = 0.037, OR 2.304, 95% CI 1.053-5.042) as independent predictors of a leak.

CONCLUSIONS

Within this surgical unit, the incidence of leaks from intraabdominal anastomoses was relatively low. However, leaks in patients undergoing extraperitoneal anastomoses continue to be a major cause of morbidity and mortality.

Randomized clinical trial of bowel preparation with a single phosphate enema or polyethylene glycol before elective colorectal surgery

BACKGROUND

A recent meta-analysis has questioned the value of bowel preparation in patients undergoing colorectal resection. The aim of this clinical trial was to evaluate whether a single phosphate enema was as effective as oral polyethylene glycol (PEG) solution in preventing anastomotic leakage.

METHODS

Patients were randomized to receive either a single phosphate enema or 3 litres of oral PEG solution before surgery. Patients were followed for a minimum of 6 weeks to detect anastomotic leakage.

RESULTS

There were 147 patients in each group and the groups were evenly matched for putative risk factors at baseline. Patients in the enema group had more anastomotic leaks requiring reoperation than those in the PEG group (4.1 versus 0 per cent, P = 0.013; relative risk 2.04 (95 per cent confidence interval (c.i.) 1.82 to 2.30)). The mortality rate was higher in the PEG group (2.7 versus 0.7 per cent, P = 0.176; odds ratio 1.62 (95 per cent c.i. 0.45 to 36.98)).

CONCLUSION

Bowel preparation with a phosphate enema was associated with an increased risk of anastomotic leakage requiring reoperation compared with oral PEG. These results do not support the routine use of a phosphate enema in patients undergoing elective colorectal surgery.

Sperm banking in adolescent cancer patients

BACKGROUND

Semen cryopreservation is a widely available method of maintaining fertility in male cancer patients. However this facility is not always used.

AIMS

To identify the barriers to successful sperm banking in a group of adolescent and young adult patients.

METHODS

Questionnaires were administered to 55 patients aged 13-21 years who had received potentially gonadotoxic therapy between 1997 and 2001 and had been offered sperm banking.

RESULTS

Forty five questionnaires were completed; 67% of respondents were able to bank sperm. Those who had been unsuccessful were younger and described higher levels of anxiety at diagnosis and greater difficulty in talking about fertility. They also described less understanding of sperm banking at the time of diagnosis.

CONCLUSION

Most adolescent cancer patients who have been offered fertility preservation are able to bank sperm. Younger patients may be helped by the provision of high quality information and more open discussion of the technique.

Detection of recurrence in childhood solid tumors

BACKGROUND

Frequent follow-up and regular investigation are routine in pediatric oncology. However, there is little evidence regarding their value in the detection of recurrent disease.

METHODS

The authors carried out a retrospective study of the follow-up of 186 children with solid tumors who were diagnosed between 1992 and 1996. The numbers of clinic visits, follow-up investigations, and (if appropriate) the mode of recurrence detection were recorded.

RESULTS

The mean follow-up was 5.9 years. During this time, 37 recurrences were detected, symptomatically in 54% of patients, by routine investigation in 30% of patients, and at routine clinic appointment in 16% of patients. It was calculated that routine magnetic resonance imaging detected 1 recurrence for every 42 scans performed, routine computed tomography detected 1 recurrence for every 129 scans performed, and routine chest radiography detected 1 recurrence for every 257 films.

CONCLUSIONS

The current results raise questions regarding the usefulness of such follow-up in children with solid tumors.

Recent advances in understanding apoptosis: new therapeutic opportunities in cancer chemotherapy

Major advances have been made in our understanding of the regulation of the molecular machinery of apoptosis in vitro. Molecules linking proliferation and apoptosis in healthy cells are being identified and here apoptotic cell death provides the 'fail-safe' mechanism to counteract excess proliferation. More recently, pioneering work on the regulation of apoptosis, in animal models of tumour development, has shown that suppression of apoptosis in the presence of a proliferative stimulus is sufficient for tumour development. Progress has also been made towards clarifying the contribution of drug-induced apoptosis to tumour response. With increasing evidence that failure to engage apoptosis after drug treatment contributes to drug resistance in vivo comes renewed confidence that new therapeutic approaches based on drug targets in apoptotic pathways will improve the treatment of cancer patients. As ever, tumour specificity is the major issue to be resolved.

Mortality, morbidity and functional outcome after ileorectal anastomosis

BACKGROUND

Total colectomy with an ileorectal anastomosis (IRA) is a commonly performed operation. Postoperative mortality and morbidity are reported to be low and functional outcome is generally rated as good to excellent. The aim of this study was to review postoperative mortality, morbidity and functional results in an effort to identify risk factors predictive of a poor outcome.

METHODS

Some 215 patients (118 women and 97 men) with a median age of 33 (interquartile range (i.q.r.) 25-47) years underwent an IRA between November 1990 and December 1999. Median follow-up was 2 years 9 months (i.q.r. 1-5 years). The clinical notes of these patients were reviewed retrospectively to analyse the postoperative course, bowel function and long-term clinical outcome.

RESULTS

The indications for surgery included familial adenomatous polyposis (52.1 per cent), Crohn's disease (14.4 per cent), functional bowel disorder (14.4 per cent), ulcerative colitis (8.4 per cent) and colonic carcinoma (4.7 per cent). The overall 30-day mortality and morbidity rates were 0.9 and 26.0 per cent respectively. This included anastomotic leak (6.5 per cent), small bowel obstruction (14.4 per cent), fistula (2.8 per cent) and anastomotic stricture (1.4 per cent). The incidence of fistula and anastomotic stricture was significantly higher in Crohn's disease (P < 0.001 and P = 0.005 respectively). Only 16 of 31 patients with Crohn's disease had a functioning IRA at long-term follow-up. Median stool frequency was 3 (i.q.r. 3-5) per day one year following surgery and did not change with longer follow-up.

CONCLUSION

Mortality and morbidity rates following IRA are low. Postoperative fistula and anastomotic stricture are more common in patients with Crohn's disease, approximately half of whom will eventually need a permanent ileostomy. Long-term bowel function for all groups is satisfactory.

Targeting apoptosis in cancer chemotherapy

The aim of cancer biology is for a better understanding of the molecular basis of cancer, with the expectation that this will result in therapeutic advances and improved outcomes for patients. The discovery of apoptosis has contributed much to our understanding of the mechanisms of cell death, in both normal and neoplastic cells, and it has led to changes in the way that chemotherapy has been viewed. It is now increasingly accepted that part of the efficacy of conventional chemotherapeutic drugs is due to their ability to induce apoptosis, although this area is not without controversy. This has allowed advances in the fundamental understanding of apoptosis to have similar impacts upon cancer biology. It is now possible to construct a framework where cellular decisions about life and death can be seen as the result of a balance of pro- and anti-apoptotic signals, enacted by protein members of the Bcl-2 family, controlling mitochondrial cytochrome c release. This framework has allowed the importance of providing death signals and abrogating survival signals to both be appreciated. A range of novel approaches to the induction of apoptosis by downregulating survival signalling are described. In addition, many alternative strategies aimed at targeting particular molecular abnormalities of neoplastic cells as a means of inducing apoptosis are also under investigation and several of these are discussed. The mechanistic understanding of cell death will have profound impacts upon the practice of oncology and outlook for many patients.

Apoptosis and cancer chemotherapy

The explosion of interest in apoptosis amongst cancer biologists has been underpinned by the hope that a mechanistic understanding of cell death will inform our understanding of tumour drug resistance. A framework for drug-induced apoptosis can now be described in which a balance exists between intrinsic and extrinsic survival signals and drug-induced death signals. Pro- and anti-apoptotic signals impact upon pro-apoptotic members of the Bcl-2 family of proteins, which ultimately control the cellular fate. This framework suggests multiple points at which therapeutic interventions could be made to overcome drug resistance and, in addition, generates novel molecular targets for the induction of apoptosis in cancer cells.

The success of paediatric oncological research

The current health service climate has focussed attention on the lack of a solid evidence base for much accepted practice in medicine. Paediatric oncology is more fortunate than most specialties in being able to draw on an evidence base for much of its practice. The speciality has benefitted from a history of robust randomized trials, which also serve as the basis for future improvements.

Modulating sensitivity to drug-induced apoptosis: the future for chemotherapy?

Drug resistance is a fundamental problem in the treatment of most common human cancers. Our understanding of the cellular mechanisms underlying death and survival has allowed the development of rational approaches to overcoming drug resistance. The mitogen activated protein kinase family of protein serine/threonine kinases has been implicated in this complex web of signalling, with some members acting to enhance death and other members to prevent it. A recent publication by MacKeigan et al is the first to demonstrate an enhancement of drug-induced cell death by simultaneous blockade of MEK-mediated survival signalling, and offers the potential for targeted adjuvant therapy as a means of overcoming drug resistance.

Apoptosis and cancer chemotherapy

Apoptosis is a fundamental mechanism of cell death that can be engaged by a range of cellular insults. One of the major modes of action of chemotherapeutic drugs may be via the activation of apoptosis. Understanding how the cell death program is engaged following an insult, and hence why it fails to be engaged in certain settings, offers a novel approach to overcoming the clinical problem of drug resistance. The tumour suppressor gene p53 and its downstream effector genes p21, mdm-2, and gadd45 seem to be important in the cellular response to genotoxic drug induced damage. Considerable evidence has accrued about the effect of mutations of this pathway on drug sensitivity and this is discussed. The expanding Bcl-2 family of proteins also play an important role in the cell death program. Evidence suggests that these proteins may function as integrators of damage signals, and may be the final decision point as to whether a cell lives or dies. These proteins may thus represent a logical target for new approaches to overcoming drug resistance.

X linked lymphoproliferative disease in a United Kingdom family

X linked lymphoproliferative disease (XLP; Duncan's disease) is a rare disorder affecting boys and characterised by a defective immune response to Epstein-Barr virus caused by a mutation in a gene located at chromosome Xq25. Three siblings with XLP in a single UK family are reported and the variation in phenotypic expression of the disease in these siblings described. One of the siblings with life threatening fulminant infectious mononucleosis was successfully treated by chemotherapy, followed by bone marrow transplantation using an unaffected brother as the donor. A healthy baby boy recently born into the family was identified as carrying the defective maternal X chromosome using molecular genetic linkage analysis. This family illustrates the extent of present understanding of this often fatal condition.

Hypothermic ischaemia of the liver: a re-perfusion phenomenon

BACKGROUND

The effects of hypothermic injury to the liver were investigated on an isolated perfusion circuit by comparing porcine livers with varying degrees of preservation injury.

METHODS

A group of unstored livers (n = 5) were compared to livers stored in University of Wisconsin (UW) solution for 18 h (n = 5), and a group of livers stored in Hartmann's solution for 18 h (n = 5).

RESULTS

We observed that the degree of platelet sequestration was directly related to the severity of the preservation injury. After 2 h of isolated liver perfusion, the perfusate platelet count fell from 148 +/- 14 x 10(9)/L to 84 +/- 13 x 10(9)/L for control livers. In comparison for livers stored in UW solution, the platelet count fell from 173 +/- 43 x 10(9)/L to 61 +/- 14 x 10(9)/L representing a 64.8% fall, while for those stored in Hartmann's solution, an even more profound fall from 152 +/- 36 x 10(9)/L to 19 +/- 9 x 10(9)/L (87.5% fall) was observed. The difference between the UW-stored and Hartmann's-stored livers was significant (P < 0.05). However, using this model, the degree of leukocyte sequestration did not differentiate the groups. Both histological and ultrastructural examination of liver biopsies taken immediately following revascularization demonstrated that for mild degrees of preservation injury following hypothermic storage, changes occur to the sinusoidal lining cells well before changes to the parenchymal elements.

CONCLUSIONS

These findings substantiate the hypothesis that the primary injury associated with hypothermia involves the sinusoidal lining cells (non-parenchymal elements), that it is predominantly a reperfusion phenomenon and that efforts at improving preservation should therefore be targeted primarily at these cells and not the hepatocytes.