Learn about the various causes of cancer

Simply put, cancer refers to the uncontrolled growth of abnormal cells that can arise in any part of the body. Steadily, these abnormal cells give rise to cancer cells, also known as malignant cells or tumor cells. There are over 100 different types of cancers and some cancers are characterized by the area they have originated from like breast cancer, lung cancer, etc.

Cancer cells also can infiltrate nearby cells and tissues and destroy those healthy cells and the process is known as metastasis. Frequently, cancer cells can break away from this original mass of cells, travel through the blood and lymph systems, and lodge in other organs where they can again repeat the uncontrolled growth cycle. While the symptoms of cancers look regular, some symptoms are very hard to detect. Plus, if cancer reaches an advanced stage, it might get difficult to save the day.

Cancer is the second-leading reason for deaths in the world, however with the advancement in medical science, the death rate is slowly going down. But, what causes cancer? Is it just genetics or are there any external factors that lead to cancer development? Well, if you are looking for answers, you are in the right place. In this article, we are going to discuss what are the different causes, risk factors of cancer that are known to medical science and also is there a chance to prevent cancer.

What are the Causes of Cancer?

Any factor that may cause a healthy cell to divide abnormally, can potentially cause cancer. However, many factors have been linked to cancer development. While some cancer can have unknown triggers, some cancer can have more than one trigger ranging from genetics to the environment. Many patients who develop cancer, experience it due to a combination of these factors. Although it is impossible to pinpoint to the initiating event(s) that lead to cancer, research has provided us with several likely causes. Here’s a list of the major causes:

Chemical or toxic compound exposures: Chemicals like Benzene, nickel, asbestos, cadmium, benzidine, N-nitrosamines, vinyl chloride, tobacco, or cigarette smoke can lead to cancer. Everyday exposure to these toxic compounds have shown severe effects and professionals who work in such industries need to be careful and take enough protection to keep cancer at bay. Plus, it’s a no brainer to deduce how smoking is injurious to health and can give rise to lung cancer.

External agents: Some bacteria and viruses have also shown to be responsible for cancer. Helicobacter pylori (which causes gastritis), HPV (human papilloma virus/papilloma virus, which causes changes in Cervical cells), HBV, HCV (hepatitis viruses that cause hepatitis), EBV (Epstein-Barr virus, the herpes virus that causes inflammation of the throat lymphoid) are some of the few external agents that are known to be responsible.

Radiation: Sometimes, exposure to uranium, radon, or even ultraviolet rays from sunlight, and other radiations in any form can be responsible for cancer.

Genetics: Few of the specific cancers like breast, ovarian, colorectal, prostate, skin, etc. are linked to human genes.

Other than these factors, there are a couple of risk factors that are linked to cancer. Let’s look at a few of those factors.

What are the Risk Factors of Cancer?

While your oncologist might have a fair idea of what may increase the risk of cancer, the majority of people are unaware of risk factors. Here, are few factors that needs:


Age can be an important risk factor and cancer also takes years to develop. Although a lot of people who are 65 years old or more are more susceptible to cancer, it is just not limited to older adults, and cancer can be diagnosed at any age.


A lot of lifestyle choices like smoking, drinking regularly, excessive exposure to the sun, overweight, etc. are known to increase your risk of cancer. And, taking care of these habits, early on in life can lower the risks of cancer.

Family history

Although only a small portion of cancers are the result of family genetics, it’s still a risk. So, if cancer is commonly run in your family, it’s possible to inherit mutations that are being passed from one generation to the next. So, getting yourself tested can help you lower your risks and take precautions from early on. However, don’t forget that inheriting mutations doesn’t necessarily mean you will get cancer.

Other health conditions

Certain chronic health conditions like diabetes, ulcerative colitis, can increase your risk of developing certain cancers.


Other than all the other risks, the environment to an extent is also responsible for increasing your chances of cancer. Passive smoking, exposure to chemicals like asbestos, and benzene, etc. are also associated with an increased risk of cancer.

Now that we know about the risk factors, what are the symptoms of cancer? In the next section, we will be looking at the different symptoms of cancer.

Symptoms of Cancer

Although signs and symptoms caused by cancer can vary depending on what part of the body is affected, the first few signs are similar. Here are some general signs and symptoms that are specific to cancer: 

  • Fatigue and tiredness
  • Lump or thickening of an area that can be felt under the skin
  • Unexplained weight loss or gain
  • Skin changes, like darkening, yellowing, redness of the skin, moles that enlarge or change color, sores that won’t heal
  • A cough that doesn’t go away or trouble breathing
  • Difficulty in swallowing
  • Unexplained bleeding
  • Hoarseness
  • Poor digestion or discomfort after eating
  • Unexplained muscle or joint pain
  • Night sweats

In the next part, we will be looking at how an oncologist diagnoses cancer.

How does an oncologist diagnose cancer?

Although there will be no dearth of information on the common symptoms of cancer, yet to diagnosis, there’s a lot more. While some cancers are diagnosed during regular screening examinations, some are only discovered after the symptoms arise.

To start with, medical history and a physical exam, are the first steps to diagnose cancer. Your doctor may ask you to undergo a series of tests to determine the type of cancer along with the location of cancer and the stage the cancer is in. Other than these tests, you may also have to take blood count, blood studies, Check on electrolyte levels, etc. to look for additional information that can come handy to figure the treatment plan better.

Among the routine tests to diagnose cancer, imaging studies are one of the most prominent ways to diagnose cancer. These studies help physicians detect any form of abnormalities in the body that may or may not give rise to cancer. CT Scans, X-rays, MRI scans, and ultrasound are common tools to examine the body along with other tests such as endoscopy. For some cancers like rectal cancer, an endoscopy allows the visualization of tissues in the discreet place like the intestinal tract/bronchi that may be affected. Plus, in areas that cannot be well visualized, radionuclide scanning is used to visualize the inside of the bones or in the lymph nodes.

However, the definitive diagnosis of cancer is based on a procedure called a biopsy. Here, the tissue sample is taken for examination and then analyzed by a pathologist to figure out if it is cancerous or not. While some biopsy samples are relatively easy to procure, some need a device called an endoscope equipped with biopsy attachment. The biopsy procedure helps identify the cancer type and thereby also helps to identify the stage your cancer is in. Different procedures effectively identify the stages of cancer and these stages ultimately help health professionals to figure out the amount of care the patient might need.

What is the prognosis for cancer?

The outcome for cancer is directly proportional to both the stage and type of cancer. For instance, patients with a large benign or metastasis tumor can be cured with surgery and other treatments like chemotherapy. However, if the cancer is at an advanced stage or aggressive, the prognosis decreases. As the staging numbers for cancers increase, the prognosis worsens, and the survival rate drops. On the brighter side, cancers that get treated and do not recur within the next five years, patients will have a higher life expectancy. However, there’s no guarantee of recurrence.

But, the prognosis is also not bereft of any complications. While some are specific to the type and stage of cancer, some can be due to treatment. Several complications like fatigue, Anemia, Loss of appetite, insomnia, hair loss, and much more.

The Bottom Line, Well, cancer doesn’t come knocking and can hit you anytime, so taking care of yourself is the most important aspect of it.

Read more:- Early signs of cancer

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