Global trends in incidence rates of childhood liver cancers: A systematic review and meta‐analysis

Abstract

Background Childhood liver cancers are relatively rare, hence inferences on incidence trends over time are limited by lack of precision in most studies. Objective To conduct a systematic review and meta‐analysis of published contemporary trends on childhood liver cancer incidence rates worldwide. Data sources PubMed, EMBASE, CINAHL, Web of Science. Study selection and data extraction English‐language peer‐reviewed articles published from 1 January 2008 to 1 December 2019 that presented quantitative estimates of incidence trends for childhood liver cancer and diagnostic subgroups. Review was conducted per PRISMA guidelines. Two authors independently extracted data and critically assessed studies. Synthesis Random effects meta‐analysis models were used to estimate pooled incidence trends by diagnostic subgroups. Heterogeneity was measured using the Q and I2 statistics and publication bias evaluated using Egger’s test. Results Eighteen studies were included, all based on population‐based cancer registries. Trends were reported on average for 18 years. Overall pooled estimates of the annual percentage change (APC) were 1.4 (95% confidence interval [CI] 0.5, 2.3) for childhood liver cancers, 2.8 (95% CI 1.8, 3.8) for hepatoblastoma and −3.0 (95% CI −11.0, 4.9) for hepatocellular carcinoma. Sub‐group analysis by region indicated increasing trends for childhood liver cancers in North America/Europe/Australia (APC 1.7, 95% CI 0.7, 2.8) whereas corresponding trends were stable in Asia (APC 1.4, 95%CI −0.3, 2.7). Publication bias was not detected for any of these analyses. The I2 statistic indicated that the heterogeneity among included studies was low for combined liver cancers, moderate for hepatoblastoma and high for hepatocellular carcinoma. Conclusions Incidence is increasing for childhood liver cancers and the most commonly diagnosed subgroup hepatoblastoma. Lack of knowledge of the etiology of childhood liver cancers limited the ability to understand the reasons for observed incidence trends. This review highlighted the need for ongoing monitoring of incidence trends and etiological studies.

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

“…Liver cancer continues to remain a global burden, with incidence rates increasing across all ages 31,32 . Results from the current study have confirmed observations from other epidemiological studies noting the increasing incidence of hepatic cancers in children 33‐36 …”

Hepatoblastoma

“…The probability of hepatoblastoma occurring in an infant or young child varies between 0.5 and 2 cases per million children per year. The explanation for this vast difference could be due to differing age groups and the possibility that the low hepatoblastoma values given in recent individual publications originate from "old" statistics, and therefore no longer accurately depict current incidence rates (29,30). Regional peculiarities supposedly play a subordinate role (25).…”

Incidence of childhood cancer in Latin America and the Caribbean: coverage, patterns, and time trends

“…Retinoblastoma is often diagnosed and treated in specialized (ophthalmology) clinics, which are sometimes missed as data sources. The increase in incidence of hepatic tumors among males has been described; however, the reasons are unclear ( 33 ). The considerable increase in the incidence of bone tumors among males in SA may be the result of better diagnosis and would be consistent with the decreasing trend of unspecified tumor types and no increase seen in females, who also undergo growth spurt just before males.…”