Incidence, time trends and survival patterns of childhood pilocytic astrocytomas in Southern-Eastern Europe and SEER, US

Abstract

Pilocytic astrocytomas (PA) comprise the most common childhood central nervous system (CNS) tumor. Exploiting registry-based data from Southern and Eastern Europe (SEE) and SEER, US, we opted to examine incidence, time trends, survival and tentative outcome disparities of childhood PA by sociodemographic and clinical features. Childhood PA were retrieved from 12 SEE registries (N = 552; 1983-2014) and SEER (N = 2723; 1973-2012). Age-standardized incidence rates (ASR) were estimated and survival was examined via Kaplan-Meier and Cox regression analysis. ASR of childhood PA during 1990-2012 in SEE was 4.2/10, doubling in the USA (8.2/10). Increasing trends, more prominent during earlier registration years, were recorded in both areas (SEE: +4.1 %, USA: +4.6 %, annually). Cerebellum comprised the most common location, apart from infants in whom supratentorial locations prevailed. Age at diagnosis was 1 year earlier in SEE, whereas 10-year survival was 87 % in SEE and 96 % in SEER, improving over time. Significant outcome predictors were age <1 year at diagnosis diagnosis (hazard ratio, HR [95% confidence intervals]: 3.96, [2.28-6.90]), female gender (HR: 1.38, [1.01-1.88]), residence in SEE (HR: 4.07, [2.95-5.61]) and rural areas (HR: 2.23, [1.53-3.27]), whereas non-cerebellar locations were associated with a 9- to 12-fold increase in risk of death. The first comprehensive overview of childhood PA epidemiology showed survival gains but also outcome discrepancies by geographical region and urbanization pointing to healthcare inequalities. The worse prognosis of infants and, possibly, females merits further consideration, as it might point to treatment adjustment needs, whereas expansion of systematic registration will allow interpretation of incidence variations.

Malignant central nervous system tumors among adolescents and young adults (15‐39 years old) in 14 Southern‐Eastern European registries and the US Surveillance, Epidemiology, and End Results program: Mortality and survival patterns

“…26 Comparisons of the most recent UK findings (5-year survival [2001-2005], 82% and 71% for individuals aged 13-24 and 25-49 years, respectively) with our data are not feasible because they also included nonmalignant CNS tumors. 7 In accordance with previous studies of childhood CNS tumors 15,17 and other childhood and adult cancers, [27][28][29] rural residence was also associated with a worse prognosis; this indicates the important role of socioeconomic status and health care delivery in outcomes and that there is room for further improvements at a population level.…”

“…Our study also showed that male sex was independently associated with a worse prognosis, especially among older individuals and those diagnosed with astrocytomas, other gliomas, and other unspecified neoplasms. In contrast, in our previous studies of SEE data focusing on children, no sex difference in survival was identified for malignant CNS tumors; an even better prognosis for males was noted with nonmalignant childhood pilocytic astrocytoma . Several mechanisms have been implicated as contributing to the overall male vulnerability to CNS carcinogenesis .…”

“…In contrast, in our previous studies of SEE data focusing on children, no sex difference in survival was identified for malignant CNS tumors 17 ; an even better prognosis for males was noted with nonmalignant childhood pilocytic astrocytoma. 15 Several mechanisms have been implicated as contributing to the overall male vulnerability to CNS carcinogenesis. 39 Interestingly, sex disparities in CNS tumor incidence and survival are also evident across different molecular subtypes of the same histological diagnosis.…”

“…In the current study, we aimed to calculate mortality and survival patterns of malignant CNS tumors by histological subtype, sex, age group, and urbanization status among AYAs in Southern‐Eastern Europe (SEE), a region rather underrepresented in the published literature; the data were derived from a network of cancer registries operating since 1990 in 12 countries (Belarus, Croatia, Cyprus, Malta, Montenegro, Poland, Portugal, Romania, Serbia, Slovenia, Turkey, and Ukraine). To explore potential survival disparities with more affluent and developed countries, we also compared the outcomes of malignant CNS tumors among AYAs in the SEE registries and used as a benchmark publicly available data from the US Surveillance, Epidemiology, and End Results (SEER) program …”

“…To explore potential survival disparities with more affluent and developed countries, we also compared the outcomes of malignant CNS tumors among AYAs in the SEE registries and used as a benchmark publicly available data from the US Surveillance, Epidemiology, and End Results (SEER) program. [15][16][17][18]…”