People coinfected with HIV and either hepatitis B virus (HBV) or hepatitis C virus (HCV) who have low CD4 counts may be at a greater risk for liver cancer, according to a study published in the October 18 issue of AIDS.

Various studies have confirmed that HIV-positive people infected with either HBV or HCV—or both—face an increased risk of liver damage and liver-related death. The risks are particularly high in people with lower CD4 counts. No study, however, has yet determined a link between CD4 count and the risk of developing liver cancer, known as hepatocellular carcinoma.

To explore a possible link, Gary Clifford, MD, from the International Agency for Research on Cancer in Lyon, France, and his colleagues examined the medical records of a small group of 26 patients diagnosed with HBV or HCV and liver cancer from the large Swiss HIV Cohort Study (SHCS). These patients were then compared with 251 other patients with no history of liver cancer, who were also participating in the SHCS and who were similar in terms of age, sex, HIV transmission category, CD4 counts and length of follow-up.

Data on HBV and HCV infection were provided by the authors on the 26 patients who developed liver cancer. Eleven of them were infected with just HBV, 12 were infected with HCV and five were infected with both HBV and HCV. Data on HBV and HCV coinfection in the comparison group of 251 patients without cancer were not provided, but the authors state that they were similar to the group with cancer. Roughly 70 percent of all the patients had used antiretroviral (ARV) therapy.

Clifford’s team found that for every 100-cell drop in patients’ CD4 counts, there was a 33 percent increase in the likelihood of developing liver cancer. Similarly, for every 10 percent drop in CD4 cell percentage, there was a 65 percent increased likelihood of developing liver cancer. The increased risk was more pronounced in people who had acquired HIV through sexual exposure than through injection drug use. Though some studies have found a decreased risk of liver cancer in people taking ARV therapy, HIV treatment was not found to have an impact on liver cancer risk in this study.