Staging childhood cancers in Europe: Application of the Toronto stage principles for neuroblastoma and Wilms tumour. The JARC pilot study

Stage at diagnosis and survival by stage for the leading childhood cancers in Rwanda

BACKGROUND

The lack of accurate population-based information on childhood cancer stage and survival in low-income countries is a barrier to improving childhood cancer outcomes.

METHODS

In this study, data from the Rwanda National Cancer Registry (RNCR) were examined for children aged 0-14 diagnosed in 2013-2017 for the eight most commonly occurring childhood cancers: acute lymphoblastic leukaemia, Hodgkin lymphoma (HL), Burkitt lymphoma (BL), non-Hodgkin lymphoma excluding BL, retinoblastoma, Wilms tumour, osteosarcoma and rhabdomyosarcoma. Utilising the Toronto Childhood Cancer Stage Guidelines Tier 1, the study assigned stage at diagnosis to all, except HL, and conducted active follow-ups to calculate 1-, 3- and 5-year observed and relative survival by cancer type and stage at diagnosis.

RESULTS

The cohort comprised 412 children, of whom 49% (n = 202) died within 5 years of diagnosis. Five-year survival ranged from 28% (95% confidence interval [CI]: 12.5%-45.6%) for BL to 68% (CI: 55%-78%) for retinoblastoma. For the cancers for which staging was carried out, it was assigned for 83% patients (n = 301 of 362), with over half (58%) having limited or localised stage at diagnosis. Stage was a strong predictor of survival; for example, 3-year survival was 70% (95% CI: 45.1%-85.3%) and 11.8% (2.0%-31.2%) for limited and advanced non-HL, respectively (p < .001).

CONCLUSION

This study is only the second to report on stage distribution and stage-specific survival for childhood cancers in sub-Saharan Africa. It demonstrates the feasibility of the Toronto Stage Guidelines in a low-resource setting, and highlights the value of population-based cancer registries in aiding our understanding of the poor outcomes experienced by this population.

Estimation of the optimal radiotherapy utilization rate for childhood neuroblastoma

BACKGROUND AND PURPOSE

The optimal utilization rate of radiotherapy (oRUR) serves as a benchmark for assessing service demand and improving access to cancer care. While it is estimated that approximately 50 % of adult cancer patients require external beam radiotherapy during their treatment, there is a scarcity of data regarding the optimal use of radiotherapy in pediatric cancer. In this study, we adopted an established method and developed a model to estimate the oRUR in childhood neuroblastoma.

MATERIALS AND METHODS

We developed a decision tree model to calculate the oRUR using indications for radiotherapy and corresponding epidemiological data collected through systematic review and meta-analysis. Sensitivity analyses were performed to evaluate the impact of variations in radiotherapy indications between treatment protocols and variables in the model. We calculated and compared the oRUR for global, high-income, and low- and middle-income settings.

RESULTS

The oRUR for pediatric neuroblastoma was 64 % (95 % CI: 58 %-71 %) in the global setting, 50 % in high-income countries, and 68 % in low- and middle-income countries. The impact of variation in radiotherapy indications between major international treatment protocols was negligible.

CONCLUSION

The knowledge of oRUR is crucial for evaluating current practices, identifying gaps in access, and planning future radiotherapy services for treating childhood cancer. Based on our results, 64 % of children with neuroblastoma have an indication for radiotherapy. Patients in low- and middle-income countries have more indications for radiotherapy than those in high-income countries, due to a more adverse tumour stage distribution caused by limited access to healthcare resources.

The feasibility of implementing Toronto childhood cancer stage guidelines and estimating the impact on outcome for childhood cancers in seven pediatric oncology units in sub-Saharan Africa. A study from the Franco-African Pediatric Oncology Group

BACKGROUND

The improvement of childhood cancer outcome is determined by early diagnosis, effective treatment, supportive care, and adequate medical follow-up. Stage at diagnosis may reflect timeliness of diagnosis, therefore standardized registration of stage is essential for interpretation of regional differences and time trends in survival. Here, we describe the feasibility of implementing the Toronto Childhood Cancer Stage Guidelines (hereafter Toronto Guidelines [TG]) in the hospital-based cancer registry of the Franco-African Pediatric Oncology Group (GFAOP), and assess the impact of TG stage on outcome in pediatric oncology units (POUs) in seven low- and middle-income countries in sub-Saharan Africa (SSA).

METHODS

All cancer patients diagnosed before 15 years of age with one of the 15 cancer types defined in TG, resident in one of the participating countries, and attending one of the selected POUs in 2017-2019 were included. Stage was assigned according to TG. Patients were followed-up for vital status for at least 12 months post diagnosis. Survival at 3, 6, and 12 months was calculated using Kaplan-Meier method and compared between POUs and tumor groups using log-rank test.

RESULTS

TG stage was assigned to 1772 of 2446 (89%) cases diagnosed with one of 11 cancer types. It was not possible to assign TG stage to acute lymphoblastic leukemia (ALL) and the three types of the central nervous system tumors included in the TG. One-year overall survival (OS) was 58% [95% confidence interval: 55-60] and varied between POUs. Survival declined with increasing stage for four tumor types and was statistically significant for two.

CONCLUSION

Except for ALL and brain tumors, we demonstrated feasibility of TG implementation for childhood solid cancers in participating POUs in SSA, and provided a baseline assessment of childhood cancer outcomes against which future stage distribution and survival can be measured as timelines of diagnosis improve over time within the GFAOP network.

Enhancing information on stage at diagnosis for childhood cancer in Africa

BACKGROUND/PURPOSE

Stage at diagnosis is an important metric in treatment and prognosis of cancer, and also in planning and evaluation of cancer control. In sub-Saharan Africa (SSA), for the latter, the only data source is the population-based cancer registry (PBCR). For childhood cancers, the 'Toronto Staging Guidelines' have been developed to facilitate abstraction of stage by cancer registry personnel. Although the feasibility of staging using this system has been shown, there is limited information on the accuracy of staging.

METHODS

A panel of case records of six common childhood cancers was established. A total of 51 cancer registrars from 20 SSA countries staged these records, using Tier 1 of the Toronto guidelines. The stage that they assigned was compared with that decided by two expert clinicians.

RESULTS

The registrars assigned the correct stage for 53%-83% of cases (71% overall), with the lowest values for acute lymphocytic leukaemia (ALL), retinoblastoma and non-Hodgkin lymphoma (NHL), and the highest for osteosarcoma (81%) and Wilms tumour (83%). For ALL and NHL, many unstageable cases were mis-staged, probably due to confusion over the rules for dealing with missing data; for the cases with adequate information, accuracy was 73%-75%. Some confusion was observed over the precise definition of three stage levels of retinoblastomas.

CONCLUSIONS

A single training in staging resulted in an accuracy, for solid tumours, that was not much inferior to what has been observed in high-income settings. Nevertheless, some lessons were learned on how to improve both the guidelines and the training course.

Cancer data quality and harmonization in Europe: the experience of the BENCHISTA Project - international benchmarking of childhood cancer survival by stage

Introduction

Variation in stage at diagnosis of childhood cancers (CC) may explain differences in survival rates observed across geographical regions. The BENCHISTA project aims to understand these differences and to encourage the application of the Toronto Staging Guidelines (TG) by Population-Based Cancer Registries (PBCRs) to the most common solid paediatric cancers.

Methods

PBCRs within and outside Europe were invited to participate and identify all cases of Neuroblastoma, Wilms Tumour, Medulloblastoma, Ewing Sarcoma, Rhabdomyosarcoma and Osteosarcoma diagnosed in a consecutive three-year period (2014-2017) and apply TG at diagnosis. Other non-stage prognostic factors, treatment, progression/recurrence, and cause of death information were collected as optional variables. A minimum of three-year follow-up was required. To standardise TG application by PBCRs, on-line workshops led by six tumour-specific clinical experts were held. To understand the role of data availability and quality, a survey focused on data collection/sharing processes and a quality assurance exercise were generated. To support data harmonization and query resolution a dedicated email and a question-and-answers bank were created.

Results

67 PBCRs from 28 countries participated and provided a maximally de-personalized, patient-level dataset. For 26 PBCRs, data format and ethical approval obtained by the two sponsoring institutions (UCL and INT) was sufficient for data sharing. 41 participating PBCRs required a Data Transfer Agreement (DTA) to comply with data protection regulations. Due to heterogeneity found in legal aspects, 18 months were spent on finalizing the DTA. The data collection survey was answered by 68 respondents from 63 PBCRs; 44% of them confirmed the ability to re-consult a clinician in cases where stage ascertainment was difficult/uncertain. Of the total participating PBCRs, 75% completed the staging quality assurance exercise, with a median correct answer proportion of 92% [range: 70% (rhabdomyosarcoma) to 100% (Wilms tumour)].

Conclusion

Differences in interpretation and processes required to harmonize general data protection regulations across countries were encountered causing delays in data transfer. Despite challenges, the BENCHISTA Project has established a large collaboration between PBCRs and clinicians to collect detailed and standardised TG at a population-level enhancing the understanding of the reasons for variation in overall survival rates for CC, stimulate research and improve national/regional child health plans.

International Comparisons of Clinical Demographics and Outcomes in the International Society of Pediatric Oncology Wilms Tumor 2001 Trial and Study

International comparisons of patient demographics, tumor characteristics, and survival can shed light on areas for health care system improvement. The International Society of Pediatric Oncology Wilms Tumor 2001 trial/study registered patients through national clinical study groups in Western Europe and Brazil. This retrospective post hoc analysis of the International Society of Pediatric Oncology Wilms Tumor 2001 database aims to make visible and suggest reasons for any variations in outcomes.

International variation in Wilms tumor survival parallels disease burden at diagnosis.

Childhood head and neck cancer in France: Incidence, survival and trends from 2000 to 2015

INTRODUCTION

Childhood head and neck cancers (HNC) are rare and represent a complex group of anatomical topographies. The aim of this study is to describe the distribution, the incidence and survival rates of children with malignant HNC in France.

METHODS

A population-based study was conducted between 2000 and 2015 in children less than 15 years with a diagnosis of HNC using the French National Registry of Childhood Cancers database (RNCE). Age-standardized incidence rates (ASR) and survival analysis were performed.

RESULTS

The 1623 included HNC represented 5.6% of all cancers included in the RNCE. The thyroid was the leading tumor site category (26.6%), followed by head and neck soft tissue location (15.4%) and the nasopharynx (10.8%). The most common cancers were thyroid gland carcinomas (26.1%), rhabdomyosarcomas (23.9%) and Burkitt Lymphomas (8.6%). Nasopharynx cancers and soft-tissue sarcomas were statistically more frequent in boys, while thyroid carcinomas were significantly more frequent in girls. The annual ASR was 8.6 new cancer cases per million children. For all HNC combined, the 5-year overall survival (OS) was 87.7% [95%CI: 85.9-89.2]. There was no statistically significant variation in 5-year OS between 2000-2007 and 2008-2015.

CONCLUSIONS

Epidemiological data on HNC distribution, incidence and survival contributes to better understand these tumors by quantifying their impact on the French population and assessing their burden. Regarding the exclusion of topographies and some histological origins performed by some authors, this report proposes new recommendations to study HNC in a pediatric population.