Thursday, December 16, 2021

50 Years of the other "C-Zero"

If you had 10 Canadians gathered together in a room, and you asked “How many of you think you will develop cancer?”, odds are no one would raise their hands. 

Like divorcing after marriage, no one thinks they will get cancer (or divorced!).  But like divorce, cancer is something many people will experience (4 out of 10 Canadians), and a few will even have multiple cancer diagnoses (and divorces!).  Approximately 2.5 out of 10 of my compatriots will die from cancer.(stats here)

Cancer is not only a problem for my compatriots.  Globally cancer kills approximately 10 million people every single year.  Cancer is the second leading cause of death in the world.  Nearly half-a-century ago President Nixon declared a “war on cancer”, the goal of which was to eliminate cancer as a cause of death.  Let’s call this project CANCER-ZERO.  The video above outlines the first 40 years of this campaign.

50 years later, with billions of research dollars being invested in cancer research every single year for nearly half a century, not a not a single type of the 200+ types of cancer have been eliminated.  Not a single one.  Let that sink in.  It is reason for humility, humility for how little we truly understand the complexities of our biological lives and humility for what science can realistically deliver. 

In the video Dr. Otis Brawley, then Chief Medical Officer of the American Cancer Society remarks:  

“I wish that we had tried to convince people that this was an investment in research that was long-term. I wish some people had not assumed we would make tremendous insights very quickly. Unfortunately human nature is such that if people had realized that this was a 40, 50 or 60 year commitment they would not have gone for it”.    

Despite the failure to realize CANCER-ZERO, the war on cancer has brought significant improvements in preventing, diagnosing and treating cancer.  We now know we can reduce some cancer risks through smoking cessation and other lifestyle changes (e.g. exercise, diet, etc.).  Improvements in diagnostics can help us catch cancer in the earlier stages of development, which makes a significant difference for survival rates.  And better cancer treatments have been developed, improving survival and quality of life for cancer patients.

50 years of the “war on cancer” has taught us that CANCER-ZERO is more of a fantasy than a feasible public health aspiration.  And the fact that most people go about living their lives in denial about their cancer risks is a mix of good and bad news.  It is good news because you do not want people ruminating about their 40%+ lifetime risk of cancer!  But at the same time, you want folks to be aware of the reality that their lifestyle choices can modulate their cancer risk factors (increasing or decreasing them).

And this takes us to the final and most significant reflection on the war on cancer.  50 years of rising cancer deaths have made vivid the importance of aging as the most significant risk factor for cancer (as well as the other diseases of late life).  I already wrote plenty about that earlier this year, so if you would like to hear more feel free to check out this article and this article.

But cancer is not exclusively a disease of older persons.  The latest issue of Lancet Oncology has this comprehensive study on the global cancer burden in adolescents and young adults (aged 15–39 years). In 2019 there were approximately 1.19 million cancer cases and 396 000 deaths due to cancer among people aged 15–39 years worldwide.

Let us see where the next 50 years of public health and advances in the biomedical sciences take us!