Childhood cancer in Indigenous populations worldwide: A systematic review

Aims: To document available evidence describing the burden of childhood cancer in indigenous peoples worldwide with a view to assessing the extent to which disparities exist in different countries.

Methods: We performed a systematic review (n = 3048) and included reports (n = 44) on cancer incidence, mortality and survival in indigenous children worldwide. We complemented articles identified through PubMed, MEDLINE, CINAHL, and SciElo, published during Jan 1980 and May 2013, with incidence and mortality data from four countries.

Results: Age‐standardized incidence of all cancers ranged from 59/million to 168/million. Indigenous children in the United States (US), Australia, New Zealand (NZ), and French Polynesia had generally similar pattern of cancer types; leukaemias, lymphomas and tumours of the central nervous system represented >50% of all cancers observed. Among indigenous children in Nigeria, two‐thirds of the cases were lymphomas. Incidence of leukaemia ranged from 6–18/million in Africa to 28–48/million in the US. Compared with non‐indigenous counterparts, indigenous children had similar or lower overall cancer incidence (20–36% lower), but varying patterns of incidence by site. Cancer mortality rates for indigenous children were available for the US, Australia, and NZ (20–39/million); five‐year all‐cancer survival for these children was 60–64%. Cancer survival was generally lower for indigenous relative to non‐Indigenous children. That was true for most studies reporting on survival of leukaemia as well as other cancer types (e.g. neuroblastoma). A few studies reported similar survival by indigenous status (e.g. Australia).

Conclusion: These data highlight the shortage of information regarding the burden of childhood cancers amongst indigenous peoples. We advocate the need for availability of childhood cancer data by indigenous status from population‐based cancer registration systems at the country level. The true extent of disparities in the cancer burden by indigenous status must be measured in order that programs for cancer control can be planned and evaluated.