A recent analysis showed that mortality from intrahepatic cholangiocarcinoma has increased globally while mortality from extrahepatic cholangiocarcinoma has leveled off or decreased.
Paola Bertuccio , PhD, from the University of Milan in Italy, and colleagues wrote that the increase in ICC-related deaths was likely due to better disease classification, whereas the decrease in ECC-related deaths likely followed the increased use of laparoscopic cholecystectomy.
“These two types of cancer have some recognized differences in risk factors and clinical presentation,” the researchers wrote. “However, ICC and ECC have rarely been studied comparatively, possibly due to difficulties in their diagnosis, registration and certification. Death certification validity from these neoplasms, however, has improved in recent years.”
Between 2002 and 2012, ICC-related mortality increased among men in all countries except Finland. The highest mortality rates were in Hong Kong with 2.5 per 100,000 men and in France, Austria, Spain, the United Kingdom, and Australia with a range of 1.5 to 1.8 per 100,000 men.
For women, ICC-related mortality rates increased in all countries except Finland, which had a decrease of 15%, and Japan, which had a decrease of 1.7%. The highest rates per 100,000 women were in Hong Kong (1.7) and the U.K. (1.5); Australia, Canada, and Austria (approximately 1.2); and Belgium, France, Switzerland, and Norway (approximately 1).
“Knowledge of risk factors helps to explain ICC trends, which showed a levelling off over recent years in ... countries that experienced a decrease in alcohol-related chronic liver disease and cirrhosis in the recent past,” Bertuccio and colleagues wrote. “In contrast, ICC rates remain upwards in other countries, including most European and American ones, which over recent calendar periods showed increases in the prevalence of [hepatitis C] infection, heavy alcohol consumption, overweight and obesity, and [nonalcoholic fatty liver disease].”
ECC-related mortality rates decreased in most countries for both men and women. Between 2010 and 2014, ECC-related mortality rates were less than 1 per 100,000 men in all countries except Japan (2.8). During the same period, the researchers observed similar decreases for women with the highest rates in Japan (1.4 per 100,000 women), followed by Austria, Germany, and other central European countries.
“A plausible explanation for the generalized decrease in ECC mortality is the increasing use of cholecystectomy, facilitated by laparoscopic techniques over the last decades given the known strong association between gallstones and the risk of ECC including gallbladder,” the researchers wrote.
They added that the less strong association of ECC with major liver diseases and cancer risk factors, compared with ICC, was also compatible with more favorable incidence and mortality trends.
“The divergent mortality trends observed for ICC and ECC suggest that they have at least partially different etiologies,” Bertuccio and colleagues concluded. “Our study provided strong confirmatory evidence on a global increase in mortality from ICC, whose determinants need to be better understood by conducting targeted investigations. Such studies should consider ICC separately from ECC.” – by Talitha Bennett
Disclosure: The authors report no relevant financial disclosures.