Epidemiology

Hepatocellular carcinoma rates rising in AIDS patients

Last Updated: 2012-07-09 16:30:18 -0400 (Reuters Health)

By Will Boggs MD

NEW YORK (Reuters Health) - The rate of hepatocellular carcinoma (HCC) in AIDS patients has gone up over the past two decades, National Cancer Institute researchers say.

"The rising incidence itself was not surprising, since HCC rates have also increased in the general population," Dr. Vikrant V. Sahasrabuddhe told Reuters Health in an email. "However, what was surprising was that despite improving regimens of antiretroviral therapy between 1990 and 2009, individuals with AIDS continued to have three to four times excess risk of HCC as compared to the general population."

For now, while researchers are trying to determine what underlies these findings, Dr. Sahasrabuddhe says doctors "should continue to focus on reducing risk of chronic liver disease (the precursor to HCC) among HIV-positive persons who are, or who may become infected with, hepatitis C and/or hepatitis B viruses."

"This may include counseling on risk factor modification, HBV vaccination, and better management of both HIV and HCV/HBV infections," he added.

It's been unclear how the availability of highly active antiretroviral therapy (HAART) might have shaped the pattern of HCC in AIDS patients over time. HAART could have reduced the risk by improving immune control of the hepatitis B and C viruses, or the prolonged survival it provides could increase the risk by increasing the duration of chronic liver disease.

Dr. Sahasrabuddhe and colleagues at the NCI in Rockville, Maryland, used data from the US HIV/AIDS Cancer Match Study to investigate the epidemiology of HCC and other hepatobiliary cancers in AIDS patients.

The overall incidence of HCC -- 16.9 cases per 100,000 person-years -- was 3.8-fold higher than the incidence of HCC in the general population, the research team reported online June 26 in Cancer.

The risk of other liver and intrahepatic bile duct cancers was elevated 3.3-fold, but there was no increased risk of cholangiocarcinoma, other extrahepatic bile duct cancers, or gallbladder cancer.

The incidence of HCC was twice as high in men as in women, and it rose markedly with age (by 8- to 10-fold among those age 50 years and older compared with those age 39 and younger).

The incidence of HCC per 100,000 person-years increased significantly from 7.0 in the pre-HAART era (1990-1995) to 14.3 in the early HAART era (1996-2000) and 25.3 in 2001-2009.

CD4 cell count at AIDS onset had little impact on HCC rates, although the disease was more common in HIV-infected patients with, vs without, AIDS.

"The rising burden of HCC in HIV-infected individuals highlights the importance of additional research on this malignancy," the researchers wrote. "One unanswered question is whether the early initiation of appropriate antiviral therapies for HCV/HBV along with HAART can reduce HCC incidence. More work also needs to be undertaken to disentangle the effect of HAART on chronic liver disease and HCC."

Dr. Sahasrabuddhe also calls for research to identify and validate non-invasive markers of risk for HCC in this population. "This may allow better surveillance for HCC in higher risk individuals such as injection drug users or hemophiliacs, as well as those who are older (40+ years)," Dr. Sahasrabuddhe said. "This may also contribute to detection of HCC at earlier stages."

SOURCE: http://bit.ly/MdxaID

Cancer 2012.