(Reuters Health) - - Death rates from liver cancer in the U.S. have doubled since the 1980s and continue to rise, largely due to risk factors like hepatitis that should be the focus of better treatment and prevention efforts, researchers say.

Despite improved survival rates overall, the rise in new diagnoses of liver cancer means that death rates are still increasing faster than for any other cancer type, the study team writes in CA: A Cancer Journal for Clinicians.

“Liver cancer is one of the few cancers for which death rates are increasing, even though many of the risk factors for the disease are avoidable or treatable. It also continues to be one of the most fatal cancers, with only about 1 in 5 patients surviving 5 years after diagnosis,” study author Kimberly Miller told Reuters Health by email.

“Large racial and socioeconomic disparities in liver cancer death rates still exist, reflecting differences in the prevalence of risk factors and, to some extent, inequalities in access to high quality care,” added Miller, an epidemiologist with the American Cancer Society in Atlanta.

The researchers examined nationwide data on incidence, mortality and survival rates for cancers of the liver and bile duct between the years 1990 and 2012, and focused on differences in these categories by region, race or ethnicity.

Rates of death from liver cancers ranged from 5.5 per 100,000 population in non-Hispanic whites to 11.9 per 100,000 in American Indians/Alaska Natives, the study found.

The lowest death rates were in North Dakota, at 3.8 per 100,000, and the highest were in the District of Columbia with 9.6 per 100,000.

“The rise in rates of new liver cancer cases has been largely driven by the higher hepatitis C virus prevalence among baby boomers (those born between 1945 and 1965),” Miller noted. “However, the obesity epidemic and rising diabetes prevalence among the general population have also likely contributed.”

Death rates are rising because liver cancer continues to be a highly fatal disease, she said.

Racial disparities in liver cancer rates are largely driven by differences in risk factor prevalence, but also in part by healthcare inequalities, she added.

“For example, while some risk factors (like hepatitis B and C virus infections) can be treated, these treatments are not always affordable for the populations that are most likely to be affected.”

It is particularly striking that while a similar proportion of liver cancer cases are diagnosed at an early stage among blacks and whites, overall liver cancer survival is notably lower in blacks, who have been shown in studies to be much less likely to receive surgical treatment and liver transplantation for early stage disease, even when they are eligible, Miller said.

In addition to chronic hepatitis B or C virus infection, factors that increase liver cancer risk include cigarette smoking, metabolic disorders (such as type 2 diabetes and obesity), and heavy alcohol use, she said.

“Many of these risk factors are avoidable or treatable. It is important to be aware of what your risk factors are and to talk to your health care provider about what you can do to lower your risk.”

The U.S. Centers for Disease Control and Prevention recommends one-time hepatitis C virus testing for those who were born between 1945 and 1965, but only 14 percent of baby boomers have been tested, Miller noted.

“I agree and support most of the result and the conclusion,” said Dr. Ping Gu, an oncologist at NYU Langone Perlmutter Cancer Center in New York who wasn’t involved in the study.

Gu, who sees a diverse population of patients, says he saw a least 50 liver cancer patients last year. Hepatitis B is the main cause of liver cancer for the Asian population, he added.

As far as prevention, hepatitis B vaccinations are extremely helpful, and tougher screening tests on blood donations have virtually eliminated the risk of hepatitis C from transfusions, Gu said.

Another preventable risk factor is obesity, which Gu said he sees “more and more” among Hispanic patients, and smoking, which is still too common in Asian communities. “I would say in Asian population, especially in Japan, Korea, and the Chinese, the male smoking rate is very high,” he said.

SOURCE: bit.ly/2sALcOS CA: A Cancer Journal for Clinicians, online June 6, 2017.