Not all cancers start the same. The environment — like tobacco products or radiation exposure — causes some cancers. Some cancers have a genetic component. But 20 percent of all cancers are caused by an infection like a bacteria or a virus. For example, the bacteria that causes ulcers is linked to stomach cancer, and the virus that causes mononucleosis can cause lymphoma.
Doctors at Fred Hutchinson Cancer Research Center are studying young cancer patients in Africa. What they learn about how they contract a virus that develops into lymphoma may help unlock the mysteries of infection-based cancers around the world and how to prevent them.
Sabrina Register: The images are heartbreaking. Children as young as 2 are suffering and dying from a form of cancer called Burkitt lymphoma.
Corey Casper: It’s the fastest growing tumor we know of today. It starts out the size of a grape and turns into the size of a grapefruit in just a few weeks.
Register: But this form of cancer isn’t caused by exposure to a harmful chemical or radiation. And it’s not genetic. It’s caused by an infection.
Casper: There are obviously many different types of infections and families. We think about viruses, bacteria, fungi and parasites. It actually turns out that all of those categories, each type of infection can cause cancer.
Register: Dr. Corey Casper is the head of global oncology at Fred Hutchinson Cancer Research Center. He studies the link between specific infections and certain types of cancers, and says the connection is clear. Some infections do cause cancer. Take the bacteria that causes ulcers, for example. It also causes stomach cancer. Hepatitis is linked to liver cancer. Human Papilloma virus causes cervical cancer. And the virus that is behind mononucleosis, Epstein-Barr? It causes lymphoma.
These bacteria that are in our schools, hospitals, homes and stuff that we come in contact with everyday, could these cause cancer?
Casper: That’s a great question, and one that might induce more fright than quell it. Seventy percent of us have one infection that we harbor chronically in our bodies that could cause cancer. But less than one percent of us develop cancer from that infection in our body.
Register: But that one percent of people who develop cancer from an infection accounts for 20 percent of all cancer cases worldwide. So, for Casper and his team, the goal is to figure out why. And they look to Africa for answers.
Casper: We know that about 60 percent of the cancers in East Africa are caused by infections — so much higher than we have here.
Register: While enormous attention has been paid to health crises like HIV, malaria and tuberculosis, the scales have tipped. Casper says that in Uganda today more people are dying from cancer than HIV, malaria, and tuberculosis combined. So he and his team are working with the children suffering from Burkitt lymphoma, hoping not just to treat them, but to find a way to prevent it through a vaccine.
Casper: The power of vaccine to eliminate cancer is incredibly potent. Cervical cancer is incredibly expensive to treat and not effective, but right now a whole course of immunization is under a couple hundred dollars and it can prevent the cancer from ever developing.
Register: Vaccines have been effective against some other types of cancer in other countries. In Taiwan, for example, liver cancer is the number one cause of cancer in children. But a Hepatitis B vaccine administered to all newborns there has all but eradicated the disease. By studying Ugandan children from birth to see which viruses they acquire, Dr. Casper and his team may unlock answers and ultimately wipe out many infection-based cancers around the globe.
Casper: In my mind, it’s a win-win situation when you can do something that helps people both in Sub-Saharan Africa and here in the United States. And I think our work really has the potential to do that.
Sabrina Register is an award-winning journalist who has been covering stories that are relevant and matter to the people of the Northwest for close to 20 years. A graduate of Vanderbilt University with a concentration in political science, Sabrina began her television career in Mississippi. After spending two years reporting in Albuquerque, New Mexico, Sabrina moved to Seattle in the mid-1990’s to cover news of the Northwest. Sabrina’s awards include top recognition from the Associated Press and the prestigious Edward R. Murrow award for investigating reporting.More stories by Sabrina Register