AUTHOR=Trallero Jan , Sanvisens Arantza , Almela Vich Fernando , Jeghalef El Karoni Noura , Saez Lloret Isabel , Díaz-del-Campo Cristina , Marcos-Navarro Ana Isabel , Aizpurua Atxega Amaia , Sancho Uriarte Patricia , De-la-Cruz Ortega Marta , Sánchez María José , Perucha Josefina , Franch Paula , Chirlaque María Dolores , Guevara Marcela , Ameijide Alberto , Galceran Jaume , Ramírez Cristina , Camblor Marta Rodríguez , Alemán Maria Araceli , Gutiérrez Pilar , Marcos-Gragera Rafael , REDECAN TITLE=Incidence and time trends of childhood hematological neoplasms: a 36-year population-based study in the southern European context, 1983–2018 JOURNAL=Frontiers in Oncology VOLUME=13 YEAR=2023 URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2023.1197850 DOI=10.3389/fonc.2023.1197850 ISSN=2234-943X ABSTRACT=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.