A new study suggests that we could cut cancer deaths by half - and reduce the rate of new cancers by up to 60 percent - all without any new treatments.
In fact, it wouldn't take any drugs at all. All we need to do is get people to follow the recommendations that doctors have been making for decades: don't smoke, drink moderately, maintain a healthy weight, and exercise regularly.
At least, that's the message from a new study that looked at the lifestyles of more than 100,000 doctors and nurses in the US.
To make this clear right up front - lifestyle alone is never going to stop all cancers. Unfortunately, a lot of the time, the disease strikes totally at random, and it can happen to even the healthiest of people.
But the new study serves as a reminder that while we often focus all our money and effort on new treatments, there are already proven ways to reduce people's risk of developing cancer.
"Some of the declines we have already seen in cancer mortality - the large decline in lung cancer - that was because of efforts to stop people from smoking," Siobhan Sutcliffe, a public health scientists from Washington University in St. Louis, who wasn't involved in the research, told Carolyn Y. Johnson from The Washington Post.
"Even while we’re making new discoveries, that shouldn’t stop us from acting on the knowledge we already do have."
So is the prevention issue really that cut and dry? You can't blame people for not following the guidelines when a lot of media coverage makes it sound like everything both causes and prevents cancer - what we can we do but throw our hands up and live our lives?
But while the occasional study might find something random, the reality is that the vast majority of research is on the same page when it comes to risk factors for cancer - cigarettes, too much alcohol, obesity, and a lack of exercise are all bad.
And that's not to mention sun exposure, because this specific study only looked at carcinoma - which are most cancers except brain and skin cancers.
To figure out just how much of a risk living an 'unhealthy' lifestyle really is, Mingyang Song and Edward Giovannucci from Massachusetts General Hospital looked at data on taken from a range of long-term studies on doctors and nurses in the US.
They divided their cohort into two groups. The 'low risk group' didn't smoke; drank no more than one drink a day for women, or two drinks a day for men; maintained a 'healthy' BMI; and regularly got 2.5 hours of moderate exercise a week, or half as much vigorous exercise. The 'high risk group' didn't meet those criteria.
All in all, almost 30,000 people were in the 'low risk group' and more than 100,000 people were at high risk (which just goes to show that even doctors and nurses don't always follow their own advice).
After looking at cancer rates, they found that up to 80 percent of lung cancer could be put down to lifestyle, as well as more than one-fifth of colon cancer, pancreatic cancer, and kidney cancer cases.
When they applied those rates to the rest of the US population, they found that between 41 and 63 percent of cancer cases could be preventable, as well as 59 to 67 percent of cancer deaths.
That's a pretty huge if you consider the fact that despite countless promising new treatments, we're still no closer to a 'cure' for cancer - the more we learn about the disease, the more complex we realise it is.
"These findings reinforce the predominant importance of lifestyle factors in determining cancer risk," the researchers write in JAMA Oncology. "Therefore, primary prevention should remain a priority for cancer control."
There are some flaws to mention in this study - it only looked at data on white doctors and nurses in the US, so there are a whole lot of demographics that weren't accounted for. Also, doctors and nurses are generally healthier than the rest of the population, so applying the findings from this group to everyone else doesn't necessarily work out so well.
And let's not get started on the fact that healthy body weight in this case was based on BMI, which a growing body of research has shown is a flawed measure of health.
But all that said, the team still had a huge sample size to look at, and found some pretty striking trends, and the overall message is that we can't forget about prevention in our search for a cure.
"There's room for both. Let’s not ignore the power of therapy and its applications for people who have cancer. ... We simply cannot ignore that," cancer researcher Tyler Jacks from MIT, who wasn't part of the study, told The Washington Post. "But why can’t we also include, as we think about cancer control more broadly, the lifestyle issues, the human behaviour issues, that can lower overall risk."