By far the most common form of cancer is skin cancer. About one in five people will have skin cancer in their lifetime, compared to about one in 18 for lung cancer and about one in 100 for liver cancer. However, only one person in 50,000 will develop heart cancer. Even when heart cancer occurs, it is 30 to 40 times more likely to be secondary, meaning it spreads to the heart from somewhere else rather than starting there.

So what makes heart cancer so rare? The answer lies in the special characteristics that differentiate the heart from other organs in the body. Studies suggest that the heart may also hold clues about how cancer forms and spreads in areas most likely to be affected.

Cancer is caused by mutations.

Cellular regeneration is one of the most essential processes in the body. This is how we grow and stay healthy by replacing damaged cells with new ones. However, sometimes errors known as mutations can occur in the regeneration process that cause it to continue far beyond what is necessary for our health. When this type of mutation is activated, new cells continue to overgrow, forming masses of tissue that deplete the body’s resources and put pressure on healthy organs. This harmful and uncontrolled growth is cancer.

While genetics and other factors influence how often cancer occurs and where, cancer-causing mutations are generally more common in parts of the body with high cell turnover. The more cell regeneration, the greater the probability of error. That’s why certain behaviors, like smoking, increase the risk of developing specific cancers. Smoking damages the tissue in the lungs, throat and mouth, which means more regeneration in those areas and more chance of a mutation occurring there.

How are heart cells different from other cells?

Unlike many other organs, the heart is made up of tough muscle tissue that grows and regenerates very slowly, at a rate of about one percent per year. Less than half of the heart cells you are born with will be replaced naturally during your life. Compare this to your skin, which completely regenerates all of its cells every 40 to 56 days.

Scientists believe that the low regeneration in the heart was an evolutionary compensation. In exchange for the organ being durable and functional from an early age, the heart lost in mammals the ability to regenerate that it still has in some other animals, such as amphibians. In the words of one study, the human heart responds to damage with “repair rather than regeneration,” developing scar tissue instead of developing new, healthy cells.

The slow regeneration of heart cells is believed to be the main reason why hearts rarely develop cancer. And when cancer spreads to the heart, it tends to grow more slowly there than in other affected areas. This is especially notable given that the bloodstream is one of the main ways cancer cells spread. Cancer cells do not affect the heart very often, even when they travel directly through it.

High blood pressure may help prevent heart cancer

A 2026 study suggests that high pressure caused by the heart’s continuous beating plays a role in preventing cancer from forming.

When the heart operates under less pressure than normal, its rate of cell regeneration increases. This can be seen in heart failure patients with an implant that relieves stress on the heart by helping to pump blood through the body. We know that increased cell regeneration in other areas of the body increases the chances of cancer developing. Could the same thing happen in the heart?

Researchers at the International Center for Genetic Engineering and Biotechnology in Trieste, Italy, sought to determine whether a heart under less pressure is more likely to develop cancer. To find out, they transplanted hearts into mice that pumped less blood than normal, meaning they were under less pressure than normal and had more regeneration. The researchers then introduced cancer cells into the transplanted hearts, as well as the hearts of normal mice, and compared how quickly they spread.

Cancer cells spread more quickly in hearts under lower pressure. Surprisingly, the researchers were able to link these changes to a specific protein affected by heartbeat. In response to the physical force and pressure of the heartbeat, this protein reduces the activity of genes related to cancer growth.

The study could pave the way for new forms of cancer treatment. Devices that produce a pulse of pressure, mimicking the heartbeat, could be used to slow or stop the spread of cancer in specific areas. Prototypes being tested for cancers close to the skin, such as breast cancer, show promising results.

There could be more to the relationship between cancer and the heart

Because heart cancer is so rare, it has not been researched as thoroughly as other types of cancer. However, some studies have proposed a direct connection between heart health and cancer in other areas of the body.

A 2026 analysis published in the Journal of the American Heart Association suggested that changes in cardiac function could be an early warning signal for the development of specific cancers.

Researchers tracked the health of thousands of patients for up to 18 years, comparing MRI scans of the patients’ heart function with their cancer rates. The study found that patients who had certain subtle changes in heart function were more likely to develop cancer in certain areas later. For example, patients with reduced function of the left atrium of the heart were more likely to develop colon cancer later in life.

Xinjiang Cai, lead author of the study, said in a statement that these “changes in the heart may occur alongside, or even before, biological processes related to cancer development.” Understanding how deep the connection is between heart health and cancer could allow doctors to detect cancer earlier.

The relationship between cancer and the heart is complex and one that scientists are still unraveling. By taking a close look at one of the organs most protected against cancer, we could transfer some of that protection to other organs.

Statistically, you probably won’t have to worry about getting heart cancer anytime soon. But someday his heart could help doctors understand cancer in other parts of the body.

In Ask us anythingPopular Science answers your most outlandish and mind-blowing questions, from the everyday things you’ve always wondered to the strange things you never thought to ask. Do you have something you’ve always wanted to know? ask us.

Awards for the House of the Future of Popular Science 2026

39 products that will improve your daily life.