What Is Cancer?

How the Development of "Immortal" Cells Lead to Cancer

What is Cancer?
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Cancer is something that we all know but one that few of us can define. While we might be fully aware that it's a "bad thing," understanding the very nature of the beast — how it starts, why it happens — is another matter altogether.

Cancer is a term that we use to describe a complex group of more than 100 different types of disease which causes the growth and spread of abnormal cells. Cancer can affect just about every organ in the body, ranging from the lungs and stomach to the eyes and heart.

Each type of cancer is unique with its own causes, symptoms, and methods of treatment, with some forms being more common than others.

The Biology of Cancer

The organs in our body are made up of cells. These cells divide and multiply as the body needs them. But when cells suddenly change and multiplying when the body doesn't need them, they can consolidate into masses or growths we call tumors.

Cancer cells are considered "immortal" because they can continue to multiply without end. Normal cells, by contrast, have a limited lifespan and will eventual die off to be replaced with others. It is why certain cancers are able to invade healthy tissue since there is nothing in their genetic makeup to temper growth.

Tumors can either be benign or malignant. Benign tumors are considered non-cancerous (meaning they can't invade neighboring tissue) while malignant ones are cancerous (meaning they have the potential to spread and invade).

Understanding Metastasis and the Spread of Cancer

The cells within a malignant tumor have the ability to spread (disseminate) by breaking free from the site of the tumor and entering the bloodstream in a process called metastasis. Metastasis can seed cancer cells throughout the body and affect multiple organ systems, making treatment all the more difficult.

Although most cancers develop and spread this way, blood cancers like leukemia do not. These affect the bone marrow and other blood-producing organs, which start churning out abnormal blood cells while suppressing healthy ones.

Symptoms of Cancer

While the symptoms of cancer can vary based on the type of cancer involved, there are some commonalities. As cancer progresses, it is not unusual to experience things like unexplained weight loss, fever, and fatigue. These are non-specific signs easily attributed to other conditions.

But, as cancer continues to advance, people will often experience organ-related issues specific to where the tumor is located. People with brain tumors, for example, might experience neurological or eyes problems, while those with colon or stomach cancer will often develop a range of gastrointestinal disorders.

Treatment of Cancer

There are four standard methods of treatment for cancer: surgery, chemotherapy, radiation therapy, and immunotherapy/biologic therapy.

When diagnosed with cancer, a cancer specialist, called an oncologist, will outline the various available treatment options. A treatment plan will then be formulated based on the type of cancer involved, how far a malignancy may have spread, and the general health/history of the individual.

Ultimately, it is the person with cancer who makes the final treatment decisions after careful consultation with the oncologist, the primary care physician, and any other second opinions he or she may need.

Cancer Prevention Tips

Many people don't realize there are ways to prevent cancer and that the disease is not, as some might suggest, inevitable.  

Smoking is the perhaps most significant risk factor that we can act upon. It is responsible for not only lung cancer but many other types of cancers, as well. As an independent factor, cigarettes can complicate almost all forms of the disease by harming the very organs key to our immune defense.

In fact, excessive sun, alcohol, fats, sugars, and other lifestyle/dietary choices have a cumulative effect that can not only increase the risk of specific cancers (including skin, liver, and colorectal) but undermine a person's biological ability to heal and thrive.

Ultimately, the best tool for cancer prevention is routine medical care. By catching an abnormality or growth early, you stand a far better chance of treatment success. This can include Pap smears, mammograms, colonoscopies, or any other investigative exams recommended by your health provider.

Source:

DeBaradinis, R. et al. "The biology of cancer: metabolic reprogramming fuels cell growth and proliferation." Cell Metabolism. 2008. 7(1):11-20.

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