M. E. Cunningham1,2, T. D. Klug2, J. G. Nuchtern1,2, B. J. Naik-Mathuria1,2 1Baylor College of Medicine,Pediatric Surgery,Houston, TX, USA 2Texas Children’s Hospital,Pediatric Surgery,Houston, TX, USA
Introduction:
Wilms’ tumor, also known as nephroblastoma, accounts for more than 90% of kidney neoplasms and 6% of all cancers in children worldwide. Survival after diagnosis and treatment is excellent in most developed countries (>90%), but underdeveloped countries throughout Africa, Asia, and Latin America continue to struggle with detection and treatment resulting in a large discrepancy in survival. The International Agency for Research on Cancer (IARC) has been collecting incidence data since the 1970s and recently released its third volume. The purpose of this study was to compare the incidence of Wilms’ tumor across countries at a global level in order to identify at-risk populations.
Methods:
The World Health Organization (WHO) International Incidence of Childhood Cancer Volume III data set, derived from independent country-based data banks, was queried to identify the incidence of Wilms’ tumor (ages 0-14 years). When multiple registries were available for a single country, the most comprehensive registry was used. The age-specific rate (ASR) per million was compared between developed, transition, and developing countries. Descriptive statistics and independent-sample Kruskal-Wallis Test were utilized.
Results:
Data was available from 75 countries spanning six global regions. The initiation of data collection ranged from 1982-2010 and was last updated between 2006-2014. The median global incidence of Wilms tumor was 7.7 [IQR 5.4-9.1] ASR/million (Figure 1) with a median male to female distribution of 0.9:1. Diagnosis was more common in children aged 0-4 years (median 15.1[IQR 11.8-18.7] ASR/million) compared to 5-9 years (4.2[2.9-5.1]) and 10-14 years (0.7[0.4-1.1]), respectively (p<0.01). Incidence ranged from 2.8 ASR/million in Thailand to 21.2 ASR/million in Mali and was higher in developed (8.9[8.4-9.6] ASR/million) and transition (9.9[9-10.5] ASR/million) countries compared to developing countries (6.1[4.9-7.4] ASR/million) (p<0.01). Of the 6 global regions, the highest incidence was in North America (9.2[9.1-9.2] ASR/million), followed by Europe (9.1[8.6-9.7] ASR/million) and Oceania (8.5[8.2-8.7] ASR/million).
Conclusion:
Wilms’ tumor is a common cancer among children worldwide. It is reported more often in developed and transitional countries; however, this may reflect incomplete data reporting from the developing world. Continued consistent data collection is needed for further elucidation of trends and allocation of resources.
