Liver Cancer: Focus On Vaccines And Curing Hepatitis C Infections
Liver cancer is the second most common cause of cancer death worldwide, killing about three quarters of a million people. It is the fifth most common cause of cancer death in the U.S.
The most common causes of liver cancer are infection with hepatitis B or hepatitis C virus. In some countries the dietary contaminant Aflatoxin, produced by molds that grow on stored grains or nuts, exacerbates the risk that hepatitis B infection will cause liver cancer.
Hepatitis B infection is almost entirely preventable by vaccination in infancy. In fact, an 80 percent decline in liver cancer rates has been observed in Taiwanese birth cohorts that have received the vaccination early in life.
While rates of infant hepatitis B vaccination are high around the world, many babies are still missing out. Universal vaccination would lead to a further decline in liver disease and liver cancer globally.
Hepatitis C causes about a quarter of liver cancer deaths worldwide. Curative therapies like the new drug Sovaldi may be another tool to prevent liver cancer. Researchers think that curing patients of their hepatitis C infection will prevent them from going on to develop liver cancer.
But the current cost of these drugs is a substantial barrier to their use in both lower-income countries and in the U.S.
However, in Egypt, public-private partnerships have made the drug available at less than 1/100th of their price in the United States. A vigorous international effort to use these new drugs to lower the number of infections would have a substantial impact on liver cancers caused by hepatitis C.
Heavier alcohol drinking also increases the risk of liver cancer (as well as cancers of the breast, esophagus, pancreas, colon and rectum). According to the World Health Organization consumption has been increasing in the two most populous countries, India and China.
Cervical Cancer: Vaccines And Pap Smears
Cervical cancer kills more than 250,000 women year worldwide, making it the fourth-leading cause of cancer death among women worldwide. In the U.S., however, it is 14th. From 1975 to 2012, the incidence of cervical cancer in the U.S. decreased by half, due to Pap smear tests screening and removal of precancerous lesions.
However, almost all cases of cervical cancer are due to infection with the Human Papillomavirus (HPV), and we now have a vaccine against the main strains of HPV. In theory, cervical cancer is almost entirely preventable if HPV vaccination before the onset of sexual activity is followed by screening in adulthood to detect precancerous lesions caused by virus strains not covered by the vaccine. Yet the vaccine is not available to most girls in the world.