Latest research has unearthed a major trend reversal in the occurrence of liver cancer. Different regions in the world have been divided into high risk and low risk regions based on the incidence of liver cancer. North America, for example, is considered low risk and Asian countries are recognized as high risk regions. Africa falls under medium risk category. However, the new research has found that cases of liver cases are growing in number in places that are considered low risk. Nevertheless, the number of cases of cancer in high risk countries is four times more than the number of cases in low risk counties and twice the number of cases in medium risk countries. Cancer Epidemiology Biomarker and Prevention journal will feature the study in the upcoming issue.The survey was undertaken by Melissa M. Center and Ahmed Jemal. They are both epidemiologists with the American Cancer Society. Cancer cases were examined for a period ranging between 1993 and 2003. Data was collected from the International Agency for Research on Cancer and included 32 worldwide registries. Study also included more detailed research on female-male ratio regarding occurrence of cancer.

Out of the 32 registries, it was found that the number of cases of liver cancer registered an increase for both men and women between 1993 and 2002 in eight registries. It was found that the maximum increase was found in countries that were considered low risk and those which are economically more developed. Regions included in this hike in number of cases were Western Europe, Oceania and North America. The reason for this increase is being attributed to increase in the use of intravenous drugs, use of contaminated injection needles, blood transfusion without screening blood and increase in the cases of chronic HCV infection.

On the other hand, it was found that the number of cases of liver cancer reduced in three Asian regions in particular and five regions overall out of 32 registries. This decrease was registered in both men and women. There was also a change in the male-female ratio of liver cancer incidence. While the ratio was 0.9 previously, it now registers 5, which means that the number of cases of liver cancer in men has registered a drastic increase. This change in ratio was found in Egypt and France. The study is a clear indication of the changing trends of liver cancer all over the world. Further studies are required in order to unearth the reason behind the shift.