Memorial Sloan Kettering exercise scientist Dr. Lee Jones, Chief of the MSK Exercise Oncology Service. He led a research team that found moderate exercise after a cancer diagnosis helps most people live longer.
For decades, it’s been known that consistent exercise can help people live healthier lives, in part by lowering the risk of cancer.
But can exercise help a person after cancer is diagnosed — potentially improving the amount of time someone might live after a diagnosis?
That was the question a team led by MSK exercise scientist Lee Jones, PhD, set out to answer. Dr. Jones is the Chief of the Exercise Oncology Service, which studies the connection between exercise and cancer.
Dr. Jones and other researchers at MSK analyzed a large data set generated by tracking adults with cancer over many years. The team found that people diagnosed with cancer who regularly exercise reduced their risk of dying from all causes by 25% compared with people with cancer who did not exercise. The median survival time was increased around five years in exercisers compared with non-exercisers.
The research led by Dr. Jones was published in the Journal of Clinical Oncology. In this interview, he explains the encouraging news his research found about exercise following a cancer diagnosis.
Does exercise extend survival after a cancer diagnosis?
Our research found that if you exercise regularly after a diagnosis of cancer, you are likely to live longer. And the benefit is significant.
The impact of exercise varies by cancer type and other factors, such as the amount of exercise people reported. But we found that people with cancer who exercised appeared to live longer and overall were less likely to die either of cancer or other serious diseases like cardiovascular disease.
How does exercise help people with cancer?
We found that exercise appeared to reduce the likelihood of dying from some forms of cancer, such as renal (kidney cell) cancer and head and neck cancer. That is good in itself, of course.
Our research also suggests that people with cancer who exercise regularly were less likely to die of all diseases — not just cancer. That’s important because it doesn’t help a person to overcome cancer only to die of another disease.
We found regular exercise can help in a few ways. First, most people who develop cancer are over 65 years old and are also prone to serious conditions such as cardiovascular disease, diabetes, and other diseases. In our research, regular exercise reduced the risk of dying from these conditions.
Also, cancer treatments can be very powerful, and some can increase the risks of health conditions, including cardiovascular disease. That’s one reason doctors carefully balance the benefit of some cancer treatments against side effects that may be toxic.
Regular exercise during cancer treatment appears to act like a good double whammy. It reduces the risk of dying from certain cancers. And the “side effect” of exercise is actually helpful because it reduces the risk of dying from causes other than cancer, such as heart disease.
That’s especially important because more people are now long-term survivors of cancer, thanks to improvements in diagnosis and treatment. In fact, in the data we analyzed, people with some forms of breast and prostate cancer were at higher risk of dying from another disease than from cancer recurring. Exercise during cancer treatment appears to help.
What is new about your research?
Other research has found that exercise is helpful during cancer treatment. However, the studies were small and only followed individuals over a short period of time after diagnosis.
We analyzed the largest data set of adults who develop cancer, called the Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial. We analyzed 11,480 people with cancer who provided complete data about their exercise — or lack of it. The project followed some individuals for up to 25 years. So our data set was very robust.
Also, the study included people with many different types of cancer. Previous studies have focused on only one cancer at a time. So our analysis gave a more comprehensive look at cancer and exercise overall.
We also found, for the first time, that regular exercise appears to help survival rates in two specific cancers: renal (kidney cell) cancer and head and neck cancer.
How much did people with cancer need to exercise to see a benefit?
The study also evaluated how much people exercised and compared that to national guidelines, which suggest at least 30 minutes of moderate exercise (brisk walking), five days per week. The data showed that performing that level of exercise produced a significant benefit in terms of overall survival for people facing cancer.
There was also some benefit for people who exercise less than the guidelines, and quite a bit more for people who exercised longer or more frequently, depending on cancer type.
It’s important for people with cancer to know they don’t need to be running marathons or something like that to see benefits from exercise.
Did exercise help with all types of cancer?
Our research found that people with most forms of cancer experienced benefit from exercise in overall survival.
However, for some cancers, exercise only benefited their survival from other diseases — not the cancer itself. Exercise did not appear to improve cancer survival in bladder, colon, endometrial (uterine), and most blood cancers, although it did positively affect survival from other diseases.
Other studies have shown that exercise appears to improve cancer survival from these cancer types. So more work is needed.
What are the limitations of your research?
This is an observational study, meaning we found an association between exercise and a survival benefit for people with cancer. But this does not prove causality, where we can definitely say exercise is the cause of this benefit.
To do that, we need a randomized controlled trial where we carefully monitor a group who exercise and a group who doesn’t. We are doing that kind of research at MSK, but this study didn’t use that method.
Also, the data in this trial relied on people accurately reporting their level of exercise. Some people may report more exercise than they actually did.
However, this kind of research gives us a good signal that we need to investigate further. This is the first step, not the last, in finding out the role that exercise can play for people facing a cancer diagnosis.
This study was supported by AKTIV Against Cancer. Lee Jones is supported by the Memorial Sloan Kettering Cancer Center Support Grant/Core Grant (P30 CA008748) and has stock ownership in Pacylex Inc. and illumiSonics Inc.