Incidence of childhood renal tumours: An international population‐based study

Abstract

Malignant renal tumours represent 5% of childhood cancers and include types with likely different aetiology: Wilms tumour (WT), rhabdoid renal tumour, kidney sarcomas and renal carcinomas. WT is the most common renal tumour in children, previously shown to vary internationally and with ethnicity. Using the comprehensive database of the International Incidence of Childhood Cancer study (IICC), we analysed global variations and time trends in incidence of renal tumour types in children (age 0-14 years) and adolescents (age 15-19 years). The results were presented by 14 world regions, and five ethnic groups in the US. We included 15 320 renal tumours in children and 800 in adolescents reported to the 163 contributing registries during 2001-2010. In children, agestandardised incidence rate (ASR) of renal tumours was 8.3 per million (95% confidence interval, CI = 8.1, 8.4); it was the highest in North America and Europe (9-10 per million) and the lowest in most Asian regions (4-5 per million). In the US, Blacks had the highest ASR (10.9 per million, 95% CI = 10.2, 11.6) and Asian and Pacific Islanders the lowest (4.4 per million, 95% CI = 3.6, 5.1). In adolescents, age-specific incidence rate of renal tumours was 1.4 per million (95% CI = 1.3, 1.5). WT accounted for over 90% of all renal tumours in each age from 1 to 7 years and the proportion of renal carcinomas increased gradually with age.

Characteristics and Outcome of Children with Renal Cell Carcinoma: A Narrative Review

“…Overall, this effort reveals that, in comparison to adults, RCC in children seems to occur rarely. This is in line with recent population-based studies, showing RCC to be the predominant renal tumor type in (young) adolescents, whereas it occurs rarely up to the age of 14 years [ 9 , 48 ]. Moreover, the lack of data is partly based on the fact that pediatric RCC cases have not always been part of (international) renal tumor registries or protocols for children and adolescents.…”

“…In adult RCC, there is a 2:1 male predominance [ 49 , 50 , 51 , 52 ]. Our review of pediatric RCC studies does not show convincing evidence for sex predominance, whereas recent population-based studies showed a female excess in adolescents over age 15 years [ 4 , 9 , 53 , 54 ]. With regard to tumor location, we expected and found equal distribution of left- and right-sided tumors in cases where this was specified ( n = 229) ( Table 1 ).…”

“…The median reported age at diagnosis for pediatric RCC varies between 9 and 12 years [ 4 , 9 ]. The majority of the included studies show a median age of ≥10 years, although pediatric RCC cases at the age of 1 year have been reported.…”

“…Renal cell carcinoma (RCC) is a rare pediatric renal malignancy, accounting for 3.5% of all renal neoplasms in children aged 0–14 years [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ]. However, RCC accounts for 70% of the renal cancers in children aged 15–19 years, with rapidly rising incidences after the age of 7 years to 50% of renal tumors by age 14 years [ 9 ]. Knowledge of clinical characteristics, outcome and treatment recommendations is often based on retrospective studies, which mainly describe small study populations, and the insights obtained from adult RCC.…”

Pediatric and young adult renal cell carcinoma

“…The international incidence of childhood cancer volume 3 (IICC‐3) shows that the annual incidence of pediatric RCC is increasing globally, almost doubling, in 0‐ to 19‐year‐olds between the 1990s and 2010s (Supporting Information Figure S1). The relative incidence compared with the much commoner Wilms tumor (WT) varies with age, such that over half of all pediatric renal tumors are RCC in 14‐year‐olds, and RCC remains the predominant renal tumor type after this age 6 …”