Pediatric hepatic cancer incidence and survival: 30-year trends in Ontario, Canada; the United States; and Australia

Abstract

Background: Pediatric hepatic cancer is a rare malignancy, comprising only approximately 2% of all cancers diagnosed in children aged <15 years. The authors sought to describe trends in pediatric hepatic cancer incidence and survival in Ontario, Canada; the United States; and Australia. Methods: Children aged <15 years who were diagnosed with hepatic cancer from 1985 through 2013 were ascertained through population-based registries and followed from the time of diagnosis until December 31, 2015. Age-standardized incidence and 5-year relative survival were calculated for each jurisdiction. Multivariable flexible parametric survival models were used to explore predictors of hepatic cancer mortality. Results: A total of 794 children were identified in Ontario (148 children), the United States (400 children), and Australia (246 children). The average annual incidence increased by 2.2% (95% CI, 0.5%-4.0%) in Australia, 2.1% (95% CI, 0.9%-3.3%) in the United States, and 1.3% (95% CI, -0.4% to 3.0%) in Ontario. The 5-year relative survival rate improved from 60% to 82% (P = .08) in Ontario and 62% to 78% (P = .02) in the United States between the diagnostic periods 1985 through 1994 and 2005 through 2013, whereas in Australia the rate remained constant (between 74% and 77%) during the study period. On multivariable analysis, there was no significant difference noted with regard to the hazard of death between jurisdictions (P = .06). Older age, the presence of metastatic disease, and being diagnosed with hepatocellular carcinoma were found to be associated with mortality. Conclusions: The incidence of hepatic cancer in children appears to have increased over the last 30 years in Australia and North America. Survival differences between Australia; Ontario, Canada; and the United States observed in the 1980s and 1990s were no longer apparent and only marginal geographical differences in the hazard of mortality were observed.