28-year incidence and time trends of childhood leukaemia in former East Germany compared to West Germany after German reunification: A study from the German Childhood Cancer Registry

Impact of regional SARS-CoV-2 proceedings on changes in diagnoses of pediatric malignancies in Bavaria during the COVID-19 pandemic

The COVID-19 pandemic affected daily life significantly and had massive consequences for healthcare systems with tremendous regional differences. This retrospective study aimed to investigate whether the pandemic and resulting societal changes impacted the diagnosis of pediatric malignancies in a distinct region. Pediatric cancer cases in Bavaria (2016-2021) and SARS-CoV-2 proceedings during the peak phase of the pandemic (2020-2021) were retrospectively analyzed. All new diagnoses of pediatric malignancies reported from cancer centers in Bavaria were included. Clinical data from pre-pandemic years was compared to diagnoses made during the pandemic. Official SARS-CoV-2 reports were received from the Bavarian Health and Food Safety Authority and data on regional pandemic measures were obtained from the Healthcare Data Platform. With this design, a comprehensive analysis of the pandemic proceedings was performed. We found significantly decreased incidence-rate ratios for pediatric cancer diagnosis during the early spring peak of SARS-CoV-2 as it was observed in May during the pandemic, followed by non-significantly increased metastatic cancer diagnosis two months later. Additionally, the time-to-diagnosis of pediatric malignancies was significantly prolonged during the pandemic, and outpatient contacts were significantly reduced, although the availability of consultations remained the same. From our findings, we may hypothesize that there have been effects on pediatric cancer diagnosis during the COVID-19 pandemic at vulnerable times. Interpretation of changes remains speculative with potential causes from behavior patterns, such as hesitation, concerns, and potential societal changes during phases of public restrictions, rather than overwhelmed medical capacities. Nevertheless, specific awareness is needed to protect this patient population during potential future pandemics.

Gut microbiome immaturity and childhood acute lymphoblastic leukaemia

Acute lymphoblastic leukaemia (ALL) is the most common cancer of childhood. Here, we map emerging evidence suggesting that children with ALL at the time of diagnosis may have a delayed maturation of the gut microbiome compared with healthy children. This finding may be associated with early-life epidemiological factors previously identified as risk indicators for childhood ALL, including caesarean section birth, diminished breast feeding and paucity of social contacts. The consistently observed deficiency in short-chain fatty-acid-producing bacterial taxa in children with ALL has the potential to promote dysregulated immune responses and to, ultimately, increase the risk of transformation of preleukaemic clones in response to common infectious triggers. These data endorse the concept that a microbiome deficit in early life may contribute to the development of the major subtypes of childhood ALL and encourage the notion of risk-reducing microbiome-targeted intervention in the future.

Incidence and time trends of childhood hematological neoplasms: a 36-year population-based study in the southern European context, 1983-2018

BACKGROUND

Hematological neoplasms (HNs) are the first and most common childhood cancers globally. Currently, there is a lack of updated population-based data on the incidence of these cancers in the Spanish pediatric population. This study aimed to describe the incidence and incidence trends of HNs in children (0-14 years) in Spain using data from the Spanish Network of Cancer Registries and to compare the results with other southern European countries.

METHODS

Data were extracted from 15 Spanish population-based cancer registries between 1983 and 2018. Cases were coded according to the International Classification of Diseases for Oncology, third edition, first revision, and grouped according to the International Classification of Childhood Cancer, third edition. Crude rates (CRs), age-specific rates, and age-standardized incidence rates using the 2013 European population (ASRE) were calculated and expressed as cases per 1,000,000 child-years. Incidence trends and annual percentage changes (APCs) were estimated.

RESULTS

A total of 4,747 HNs were recorded (59.5% boys). Age distribution [n (%)] was as follows: <1 year, 266 (5.6%); 1-4 years, 1,726 (36.4%); 5-9 years, 1,442 (30.4%); and 10-14 years, 1,313 (27.6%). Leukemias were the most common group, with a CR and an ASRE of 44.0 (95%CI: 42.5; 45.5) and 44.1 (95%CI: 42.6; 45.7), respectively. The CR and ASRE of lymphomas were 20.1 (95%CI: 19.1; 21.1) and 20.0 (95%CI: 19.0; 21.1), respectively. The comparable incidence rates between our results and those of other southern European countries were similar for lymphomas, while some differences were observed for leukemias. From 1988 to 2016, the trend in leukemia incidence was stable for both sexes, with an APC of 0.0 (95%CI: -0.5; 0.7), whereas a constant overall increase was observed for lymphoma in both sexes, with an APC of 1.0 (95%CI: 0.4; 1.6).

CONCLUSION

Leukemias are the most common HNs in children, and their incidence has remained stable since 1988, whereas the incidence of lymphomas has increased every year. Lymphoma incidence is like that of other southern European countries, while leukemia incidence is similar only to that of southwestern European countries. Collaborative cancer registry projects allow for assessing epidemiological indicators for cancers such as HNs, which helps health authorities and clinicians provide more knowledge about these malignancies.

Langerhans cell histiocytosis and associated malignancies: A retrospective analysis of 270 patients

PURPOSE

The frequency of Langerhans cell histiocytosis (LCH) and associated malignancies (AM) is greater than statistically expected. Here, we analyze LCH-AM co-occurrence in both children and adults.

METHODS

Between 1991 and 2015, data were collected by regular questionnaires to members of the Histiocyte Society and searches in PubMed and Abstract Books. Patients were grouped by age at LCH diagnosis (≤ and >18 years), and types and timing of AM occurrence were plotted with respect to the LCH diagnosis. For the statistical analysis, only the first AM were considered.

RESULTS

A total of 285 LCH-AM in 270 patients were identified, 116 (43%) ≤ 18 years, and 154 (57%) >18 years. In childhood LCH-AM pairs, leukemias and myeloproliferative disorders (n = 58; 50.0%) prevailed over solid tumors (n = 43; 37.1%) and lymphoma (n = 15; 12.9%). In adults, solid tumors were reported in 61 patients (39.6%), lymphoma, and leukemias and myeloproliferative disorders in 56 (36.4%) and 37 (24.0%) patients, respectively. In most children, AM followed LCH (n = 69, 59.5%), whereas in adults, LCH and AM occurred concurrently in 69 patients (44.8%). In children, T-lineage acute lymphoblastic leukemia (ALL) and promyelocytic acute myeloid leukemia (AML) and retinoblastoma were over-represented and thyroid carcinoma in adults.

CONCLUSIONS

The largest collection of data on LCH-AM to date clearly indicates inherent relationships between specific types of AM and LCH, which may be due to therapy effects, clonal evolution, and germ-line predisposition, respectively. Prospective thorough genetic analysis is warranted and will hopefully shed light on the association of LCH and second neoplasms.

International patterns and trends of childhood and adolescent cancer, 1978-2012

Background

This study aimed to provide a detailed analysis of the temporal trends of cancer incidence rates for individuals aged 0-19 years in selected regions globally from 1978 to 2012.

Methods

Data were obtained from Volumes V-XI of Cancer Incidence in Five Continents (CI5), published by the International Agency for Research on Cancer. A total of 53 registries in 23 regions from the Americas, Asia, Europe, and Oceania that contained information on cancer incidence throughout 1978-2012 (35 years) were included in this study. Joinpoint regression was used for the analysis of trends.

Results

Most regions showed increasing trends in overall childhood cancer among children (aged 0-14 years) and adolescents (aged 15-19 years). Nearly all regions showed rising trends in childhood and adolescent leukemia incidence rates, whereas the incidence of lymphoma among children generally decreased. Only France, Australia, and New Zealand showed decreasing trends for malignant central nervous system (CNS) tumors among adolescents. Kidney cancer and bone cancer incidence rates remained stable for most regions. The incidence of thyroid cancer among adolescents increased in most regions and that of testicular cancer decreased in approximately one-half of the regions studied.

Conclusion

The international temporal trends of cancer incidents among children and adolescents are varied by region, cancer type, age group, and gender, and have changed over time.