Monday, October 10 2016
Why haven’t we won the war on cancer?
Cancer is the second leading cause of death in the US, killing nearly 600,000 people annually and only slightly behind heart disease in overall mortality. President Richard Nixon signed the National Cancer Act of 1971 into law, declaring a “war on cancer,” with the hope that the battle would be quickly won. But 45 years later, after the investment of billions of dollars by the US government, private industry, and charitable foundations, the war wages on.
Part of the problem is that cancer is not a disease like smallpox or cholera, in which we can wipe out the virus or bacteria that causes disease, or for which we can develop therapies to help the body fight it. Instead, cancer is a disease in which the body turns against itself. In cancer, cells begin growing out of control, often losing their original functions, and eventually invading other sites around the body, disrupting tissues and organs, and draining resources from other essential processes.
In the war on cancer, we have made an investment in a triad of interventions: prevention, detection, and treatment. Prevention is the easiest to understand, but at best we can reduce our risk. Cancers arise because of a combination of genes, environment, and chance. We can’t change our genetic risk, we can’t eliminate random chance, but we can intervene in the environment. There are many environmental factors known to contribute to cancer risk. Lung cancer, which kills more people than any other cancer, is largely driven by smoking and smoke exposure. And while public education investments have dramatically decreased smoking rates, cigarettes and smoke exposure remain the most significant “preventable” source of cancer.
There are other interventions that can lower our risk of cancer. Vaccinating pre-teens against the human papilloma virus (HPV) can reduce incidence of some cancers later in life, including those of the cervix, penis, anus, and head and neck. Taking an 81mg baby aspirin daily has been shown to reduce incidence of colorectal cancer (ask your doctor before starting to take daily doses of aspirin). And the World Cancer Research Fund estimates that about 20% of all cancers diagnosed in the US are related to body fatness, physical inactivity, excess alcohol consumption, and poor nutrition, and thus could also be prevented[1].
Detection is the area where we’ve made progress. The earlier we catch cancer, the more likely the disease can be cured through surgery or chemotherapy. But while we are developing more sensitive and specific detection methods, many, like colonoscopy (recommended for men and women starting in their 50’s) and mammograms are not performed as regularly as they should be. New technologies that look for circulating tumor cells or tumor DNA are now getting a lot of attention in hopes that accurate blood tests may one day be used to screen for cancer.
And finally, there are new therapies. As we have come to recognize that even cancer of a single tissue is a diverse, complex disease, new “targeted therapies” coupled with diagnostic tests are starting to usher in the use of “precision medicine” in which therapies are tailored to each patient based on their tumor’s unique genetic mutations. And immunotherapies, in which a patient’s immune system is activated to fight their tumor, are now making their way into the clinic. But even with the best therapies, cancer is an elusive beast—one that is changing and adapting in each patient, trying to escape eradication.
While we have made great progress, more work needs to be done. That’s why your contributions through Haymakers for Hope and other charities is so important. As a cancer researcher, I can tell you that every punch you’ve taken in raising funds is a blow in the ongoing fight to defeat cancer. So thanks to all of you for your contributions. Now get back in the gym and keep fighting.
Chin down, hands up!
John Quackenbush
[1] World Cancer Research Fund /American Institute for Cancer Research. Food, Nutrition, Physical Activity, and the Prevention of Cancer: A Global Perspective. Washington DC: AICR, 2007.