Alcohol consumption caused a substantial burden of cancer worldwide in 2020 and men accounted for over three-quarters of all alcohol-related cancers, a large, population-based study has shown.
Globally, an estimated 4.1% (95% uncertainty index (UI), 3.1-5.3%) of all new cases of cancer in 2020 were attributable to alcohol consumption, Harriet Rumgay, BSc, International Agency for Research on Cancer, Lyon, France, and colleagues reported in The Lancet Oncology.
Males accounted for 76.7% of alcohol-related cancers, with cancers of the esophagus, liver and breast cancer in females accounting for most of these cases, they added.
“We urgently need to raise awareness about the link between alcohol consumption and cancer risk among policy makers and the general public,” Rumgay said in an emailed statement. “Public health strategies such as reduced alcohol availability, labeling alcohol products with a health warning and marketing bans could reduce rates of alcohol-driven cancer.”
For the study, investigators used data from the GLOBOCAN 2020 database to estimate new cancer cases attributable to alcohol consumption. The number of alcohol-attributable cancers was expressed as a population attributable fraction (PAF) which was calculated by using a theoretical minimum-risk exposure of lifetime abstention and 2010 alcohol consumption estimated from the Global Information System on Alcohol and Health. The calculation assumed a 10-year latency period between consumption of alcohol and the diagnosis of cancer.
Globally, an estimated 741,300 (95% UI, 558,500-951,000) of all new cancer cases in 2020 were caused by drinking, the authors reported. In males, alcohol consumption caused 568,700 (95% UI, 422,500-731,100) cases of cancer while in females, 172,600 (95% UI, 135,900-220,100) cases of cancer were attributable to alcohol.
Cancers with the highest PAFs were cancers of the esophagus at 31.6% (95% UI 18.4-45.7%), followed by cancer of the pharynx (22%, 95% UI, 9.0-37.8%) and the lip and oral cavity at 20.2% (95% UI, 12.1-32.2). There were, however, considerable differences in the rates of PAFs between males and females, with far higher rates of alcohol-attributable esophageal cancers in males than in females.
“The highest PAFs of all new cases of cancer were observed in Mongolia, China, Moldova and Romania,” the authors noted. But added that the lowest PAFs were found in northern Africa and western Asia including Kuwait, Libya, and Saudi Arabia at 0.3% (95% UI, 0.1-3.3%) and 0.7% (95% UI, 0.5-1.2%), respectively.
Age-standardized incidence rates of alcohol-related cancers differed slightly from those of the PAFs. For example, many central and eastern European countries had the highest, age-standardized incidence rates in males, at 23.1 per 100,000 (95% UI, 19.0-26.6 per 100,000), followed by age-standardized incidence rates of 21.5 per 100,000 (95% CI, 13.4-29.6 per 100,000) in eastern Asia.
Among females, the highest, national-level, age-standardized incidence rates were observed in northern and western European countries including Belgium, France and Ireland, the authors added.
“In every world region, the age-standardized incidence rate was higher in males than in females,” they noted—the smallest relative difference between males and females being observed in Australia and New Zealand as well as in northern and western Europe.
Separated into levels of alcohol consumption, moderate drinking, defined as less than 20 grams of alcohol a day, contributed to 13.9% of alcohol-attributable cancers, while risky drinking, defined as consuming 20 to 60 grams of alcohol per day, contributed to 39.4% of drinking-related cancers and heavy drinking (greater than 60 grams of alcohol per day) contributed to 46.7% of alcohol-related cancers.
However, because of the methodology used in the study plus the source of data analyzed, “we consider our results to provide the most comparable estimates between countries and world regions,” they stated.
At the same time, investigators cautioned that the study was carried out during the Covid-19 pandemic when changes in the reporting of cancer due to disruptions in health care were widespread.
“The Covid-19 pandemic could have also affected individuals’ total consumption of alcohol, as shown by a reported increase in the proportion of the UK population binge drinking or drinking four or more times a week observed during national lockdowns in the UK,” the authors observed.
However, with predicted increases in alcohol consumption for years to come at least in several regions of the world, “action must be taken to reduce the avoidable burden of cancer attributable to alcohol,” they suggested.
Commenting on the findings, Amy Justice, Yale University, West Haven, Connecticut, noted that estimating the effects of alcohol intake on cancer rates across countries is notoriously difficult.
“Worldwide, 26% of consumption occurs outside government-controlled channels and is not included in sales data,” she added. “Self report, our only current means of estimating relative risk by level of consumption for a population, is worse.”
Moreover, neither sales nor self reports of alcohol consumption take into account past alcohol consumption, which may have important implications for understanding associations between alcohol use and cancer.
“Alcohol use is well known to increase risk of hepatocellular cancer among individuals with obesity who have hepatitis B or C virus infection or who smoke [and t]he more they drink, the greater the risk,” Justice noted. Given that even moderate levels of alcohol consumption increase this risk, “alcohol use might have a synergistic effect. None of these effects is captured in ecological estimates.”
The global burden of alcohol-related cancer was substantial in 2020.
Males in central and eastern Europe had the highest age-standardized incidence rates of alcohol-related cancers globally.
Pam Harrison, Contributing Writer, BreakingMED™
Neither the authors nor the editorialist had any competing interests to declare.
Cat ID: 935
Topic ID: 78,935,730,935,192,144,925