Childhood and Adolescent Central Nervous System Tumours in Spain: Incidence and Survival over 20 Years: A Historical Baseline for Current Assessment

Simple Summary Central nervous system (CNS) tumours are highly common solid neoplasms in children and adolescents. Survival remains low in many countries, including Spain. While some studies have shown a rise in the incidence of these tumours in Europe, others have not. This study, the first in Spain, focused on two questions: (1) Is the incidence of CNS tumours increasing in Spanish children and adolescents? and (2) Has the survival of these patients improved? We analysed incidence in Spain across the period 1983-2007 and survival from 1991 to 2005, according to the International Childhood Cancer Classification. The incidence results revealed a stabilisation in children's overall incidence trend since the early 1990s similar to that of Southern Europe. Overall survival was lower than that in Europe, without any improvement from 1991 to 2005. Our results provide a baseline for assessing current incidence and the achievements of paediatric oncology with regard to CNS tumours in children and adolescents.Abstract Background: Central nervous system (CNS) neoplasms are highly frequent solid tumours in children and adolescents. While some studies have shown a rise in their incidence in Europe, others have not. Survival remains limited. We addressed two questions about these tumours in Spain: (1) Is incidence increasing? and (2) Has survival improved? Methods: This population-based study included 1635 children and 328 adolescents from 11 population-based cancer registries with International Classification of Childhood Cancer Group III tumours, incident in 1983-2007. Age-specific and age-standardised (world population) incidence rates (ASRws) were calculated. Incidence time trends were characterised using annual percent change (APC) obtained with Joinpoint. Cases from 1991 to 2005 (1171) were included in Kaplan-Meier survival analyses, and the results were evaluated with log-rank and log-rank for trend tests. Children's survival was age-standardised using: (1) the age distribution of cases and the corresponding trends assessed with Joinpoint; and (2) European weights for comparison with Europe. Results: ASRw 1983-2007: children: 32.7 cases/106; adolescents: 23.5 cases/106. The overall incidence of all tumours increased across 1983-2007 in children and adolescents. Considering change points, the APCs were: (1) children: 1983-1993, 4.3%<<^>> (1.1; 7.7); 1993-2007, -0.2% (-1.9; 1.6); (2) adolescents: 1983-2004: 2.9%<<^>> (0.9; 4.9); 2004-2007: -7.7% (-40; 41.9). For malignant tumours, the trends were not significant. 5-year survival was 65% (1991-2005), with no significant trends (except for non-malignant tumours). Conclusions: CNS tumour incidence in Spain was found to be similar to that in Europe. Rises in incidence may be mostly attributable to changes in the registration of non-malignant tumours. The overall malignant CNS tumour trend was compatible with reports for Southern Europe. Survival was lower than in Europe, without improvement over time. We provide a baseline for assessing current paediatric oncology achievements and incidence in respect of childhood and adolescent CNS tumours.