Liver cancer rates rise in developed countries, elderly populations
Primary liver cancer rates continue to increase in many regions of the world despite extensive efforts to prevent the disease, according to study results published in Cancer.
The worldwide spike — particularly apparent among older men — appeared to be driven primarily by cases caused by nonalcoholic steatohepatitis.
This finding suggests prevention efforts require more emphasis on obesity control and weight management, according to researchers.
“Additionally, the primary liver cancer incidence trend and pattern are highly heterogeneous among regions and populations,” Zhenqiu Liu, MD, PhD, professor of epidemiology in the School of Public Health at Fudan University in China, and colleagues wrote. “Therefore, more targeted prevention strategies are needed.”
Primary liver cancer — which includes hepatocellular carcinoma and intrahepatic cholangiocarcinoma — is the sixth most common malignancy and fourth-leading cause of cancer death worldwide. An estimated 841,000 new cases are diagnosed annually, and 782,000 people die of the disease each year.
Prior studies suggested incidence and the predominant etiology of primary liver cancer vary greatly around the world.
Liu and colleagues used data from the Global Burden of Disease Study 2017 to evaluate primary liver cancer incidence trends from 1990 to 2017 by age at diagnosis, sex, region and etiology.
Researchers determined the number of primary liver cancer cases worldwide declined during the study period among individuals aged younger than 30 years (17,381 cases in 1990 to 14,661 cases in 2017) but increased among individuals aged 30 to 59 years (216,561 cases in 1990 to 359,770 cases in 2017) and individuals aged 60 years or older (241,189 cases in 1990 to 578,344 cases in 2017).
Decreased incidence among younger adults — likely due primarily to hepatitis B virus vaccination — appeared consistent in most regions except in developed countries, where rates increased regardless of sex and age.
Population growth, aging, and greater prevalence of obesity and diabetes may have contributed to the increase in primary liver cancer among people aged 60 years or older, Liu and colleagues wrote.
A “lag effect” — caused by a considerable portion of people infected with the hepatitis B virus early in life who progress to liver cancer as they get older — also may have contributed.
Further analysis of trends by age at diagnosis revealed the following:
Diagnosis at age younger than 30 years — Age-standardized incidence rates globally declined among men (0.74 cases per 100,000 to 0.52 cases per 100,000; estimated annual percentage change [EAPC], –2.63; 95% CI, –3.2 to –2.06) and women (0.42 cases per 100,000 to 0.25 cases per 100,000; EAPC, –2.62; 95% CI, –2.98 to –2.25).
However, age-adjusted incidence rates increased significantly in North America among males (0.13 cases per 100,000 to 0.29 cases per 100,000; EAPC, 2.89; 95% CI, 2.45-3.33) and females (0.1 cases per 100,000 to 0.21 cases per 100,000; EAPC, 2.64; 95% CI, 2.24-3.04). Age-adjusted incidence also increased in Australasia and western Europe.
Globally, the most significant decline in age-standardized incidence rate for this group was for liver cancer due to hepatitis B, followed by liver cancer due to other causes and liver cancer due to hepatitis C.
In high-income regions of North America, age-standardized incidence rates increased for all five etiologies of primary liver cancer, with the most pronounced increase reported for liver cancer due to nonalcoholic steatohepatitis.
Diagnosis between ages 30 and 59 years — Age-standardized incidence rates globally declined among men (20.48 per 100,000 to 20.04 per 100,000; EAPC, –0.49; 95% CI, –0.65 to –0.33) and women (6.88 per 100,000 to 5.01 per 100,000; EAPC, –1.52; 95% CI, –1.69 to –1.35).
The decline appeared driven primarily by a decrease in liver cancer due to hepatitis B among men and women.
However, researchers reported marked increases in age-standardized incidence rates in Australasia, high-income North America, western Europe and Southeast Asia.
In North America, age-standardized incidence increased among men (3.59 per 100,000 to 9.97 per 100,000; EAPC, 4.19; 95% CI, 3.57-4.82) and women (1.49 per 100,000 to 3.08 per 100,000; EAPC, 2.81; 95% CI, 2.6-3.03).
The increase in North America appeared driven primarily by liver cancer due to hepatitis C.
Diagnosis among those aged 60 years and older — Age-standardized incidence rates increased among men during the study period (68.27 cases per 100,000 to 86.91 cases per 100,000; EAPC, 0.64; 95% CI, 0.52-0.75) but remained stable among women (EAPC, –0.06; 95% CI, –0.14 to 0.03).
Researchers reported “a significant increasing trend” in five regions: Australasia, high-income North America, western Europe, Central Asia and Southwest Asia.
In North America, age-standardized incidence rates increased among men (23.65 per 100,000 to 50.4 per 100,000; EAPC, 2.73; 95% CI, 2.58-2.88) and women (10.44 per 100,000 to 18.67 per 100,000; EAPC, 2.03; 95% CI, 1.88-2.19).
Worldwide, age-standardized incidence rates in this age group increased significantly for all five etiologies among men, with the most notable increase for liver cancer due to nonalcoholic steatohepatitis. Among women, age-standardized incidence rates increased only for liver cancer due to nonalcoholic steatohepatitis.
“Primary liver cancer in highly endemic regions has been partly alleviated due to the potent control of hepatitis, especially among young and middle-aged people,” Liu and colleagues wrote. “However, an unfavorable trend was observed in most developed countries and in elderly populations. As such, primary liver cancer prevention schedules should give more attention to nonalcoholic steatohepatitis and elderly patients.” – by Mark Leiser
Disclosures: The authors report no relevant financial disclosures.