By Evelyn Lee
September 18, 2022
UPDATED 12:00 PM EST
[Photo credit: Heart.org]
Cancer is essentially the rapid overgrowth of your body’s genetically-damaged cells. Although your risk of developing cancer can increase from your lifestyle, such as smoking, drinking excessively, or exposure to a large amount of carcinogens, a good chunk of that risk is largely out of your control and is mostly genetically-based. For instance, some women may have the BRCA1 or BRCA 2 gene, which has been correlated with a higher risk of developing breast cancer. Others may have a TP53 mutation, which prevents it from acting as a tumor suppressant. Although cancers differ in their ‘causes,’ they all originate from the body’s inability to catch and destroy cancer cell proliferation. As a result, cancer can appear almost anywhere in the body, from the brain, to the bone marrow, to the intestines. However, there is one noticeable exception: the heart.
One would assume that the heart, being such an important organ, would undoubtedly be susceptible to cancer. After all, other crucial organs such as the brain, lungs, and pancreas are all known to develop it, so why not the heart? However, the number of people who develop malignant heart sarcomas is incredibly small, with less than 2 out of 100,000 people developing it per year. Compare this to the rates of more commonly seen cancers, such as those in breasts (15.0%, 2022) or the lungs (12.3%, 2022), and one can see a clear difference between these cancers.
The reason for this has to do with the mechanisms of cell division. Each cell goes through something called a ‘cell cycle’ whenever it duplicates its genetic information, helping prevent any genetic mistakes throughout the process. However, this cycle isn’t foolproof and may sometimes miss a mistake in DNA duplication– creating a faulty cell. If it isn’t destroyed in time, it may reproduce even more damaged cells. This can result in a tumor, and in some cases, cancer. This is why organs that have a higher rate of cell division, such as the skin, stomach, and colon, also have higher rates of cancer. Exposure to mutagens and carcinogens can also affect these rates. Meanwhile, cardiac muscle cells rarely divide throughout the person’s lifetime– only around 1% of cells are replaced each year for adults. If an organ’s cells rarely divide, then the risks of developing gene mutations from the process of cell division will be very slim. And as a result, the rate of developing cancer itself would be minuscule as well, hence the extreme unlikelihood of developing heart cancer than, say, skin or lung cancer.
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“Heart Cancer: Prevalence, Symptoms and Management.” Cleveland Clinic, my.clevelandclinic.org/health/diseases/16840-heart-cancer. Accessed 11 Aug. 2022.
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