Avoidable deaths through the primary prevention, early detection, and curative treatment of cancer worldwide: a population-based study

BACKGROUND: Global disparities exist in cancer incidence, mortality, and survival. We aimed to provide estimates of avoidable deaths among people diagnosed with cancer to inform the prioritisation of interventions and narrow cancer inequalities. METHODS: National incidence estimates for 35 cancer sites in 2022 for 185 countries were extracted from the GLOBOCAN database. We estimated numbers of avoidable deaths within 5 years of diagnosis for patients diagnosed with cancer in 2022, consisting of those deaths avoidable through primary prevention (preventable deaths) and those avoidable through early detection and improved access to treatment (treatable deaths) by cancer site, country, region, and human development index (HDI) group. Preventable deaths were estimated using population attributable fractions for tobacco use, alcohol consumption, excess body weight, infectious agents, and ultraviolet radiation obtained from the literature. Treatable deaths were estimated by eliminating survival differences using 5-year net survival from the SURVCAN-3 project and additional sources. Preventable, treatable, and overall avoidable deaths as proportions of the total expected deaths within 5 years of cancer diagnosis were also calculated. FINDINGS: 5 years after cancer diagnosis, 4·5 million (47·6% [95% uncertainty interval 47·5-47·8]) of the 9·4 million expected deaths were avoidable. Of these avoidable deaths, 3·1 million (3·1-3·1; 33·2% [33·1-33·3] of total expected deaths) were preventable and 1·4 million (1·4-1·4; 14·4% [14·4-14·5]) were treatable. Lung, liver, stomach, colorectal, and cervical cancers contributed the greatest burden, collectively accounting for 59·1% of all avoidable deaths. Lung cancer was responsible for the most preventable deaths (1·1 million; 34·6% of all preventable deaths), while female breast cancer was responsible for the most treatable deaths (0·2 million; 14·8% of all treatable deaths). Disproportionately large proportions of avoidable deaths from cervical and breast cancer were observed in countries with a low or medium HDI. INTERPRETATION: Nearly half of deaths among people diagnosed with cancer globally could be avoided through primary prevention and improvements in early detection and curative cancer treatment. Global efforts are needed to tailor prevention, early diagnosis, and treatment of cancer to address inequities in avoidable deaths, especially in low and medium HDI countries. FUNDING: Erasmus Mundus Exchange Programme and French National Cancer Institute (INCa).