What Is Cancer?
Lung cancer cells growing and dividing.
Most cells in the human body grow, divide and then eventually die. When healthy cells grow, divide and then eventually die, there are mechanisms in place within these cells that help to ensure that the process is an orderly one. When these mechanisms have been damaged or altered however, cancer can result. Cancer is a disease that is characterized by the uncontrolled growth of unhealthy cells that don’t die when they are suppose to die. There are over 100 different types of cancer, and cancerous cells can develop almost anywhere in the human body. The uncontrolled growth of cancer cells can sometimes lead to the development a mass of cancerous tissue commonly referred to as a tumor.
Why Is Cancer Dangerous?
Cancer cells steal energy from healthy cells.
Cancer is dangerous for a number of reasons. Firstly, because cancer cells grow in a rapid and uncontrolled fashion, they require a lot of energy to survive. To get the energy that they need to survive, cancer cells often deprive healthy parts of the body of much needed energy. Over time, this energy deprivation can damage the body’s healthy organs. Secondly, cancer cells can enter the circulation, travelling from the part of the body that they began growing in to different, often distant parts of the body. When cancer cells travel like this, the process is called metastasis. Traveling, or metastasizing cancer cells will often damage the distant organs that they’ve traveled to. Thirdly, cancer cells can release hormones that negatively affect the way that the body functions.
What Causes Cancer?
Cancer occurs when previously healthy cells have been damaged. Once damaged, the mechanisms that control growth, division and the ultimate death of these cells have been altered. These alterations result in the development of “cancerous” cells that grow uncontrollably and that “forget” to die when they are suppose to. There are a number of different things that can damage the mechanisms within cells that control growth, division and death. Theses things can include smoking, exposure to radiation, exposure to certain viruses, exposure to cancer-causing chemicals (carcinogens), obesity, excessive exposure to certain hormones, chronic inflammation and even a lack of exercise.
What Are The Most Common Types of Cancer Worldwide?
- Colon and Rectum
- Non-Hodgkin lymphoma
What Are Symptoms of Cancer?
Many of cancer’s symptoms depend on the type of cancer present, where it first started to grow, whether or not it has spread, and if it has spread, where it has spread to. There are however some very general cancer symptoms that can be seen with many different types of cancer. They can include;
- Weight changes (gain and loss)
- The presence of lumps that can be felt beneath the skin
- Changes in skin appearance (i.e. darkening, yellowing, reddening, developing new moles, etc.)
- Constant cough
- Difficulty breathing
- Changes in bowel habits
- Changes in bladder habits
- Muscle and/or joint pain
- Frequent fevers
- Unexplained bruising or bleeding.
How Is Cancer Diagnosed?
A Doctors physical exam, laboratory tests, imaging tests and biopsies can all be used to diagnose cancer.
- Physical Exam: Many of the symptoms of cancer listed above (including weight changes, the presence of lumps, skin changes, etc.) can be detected on a Doctor’s physical exam.
- Laboratory tests: Laboratory tests analyzing body fluids like blood and urine may reveal abnormalities consistent with cancer.
- Imaging tests: Imaging tests like computerized tomography (CT) scans, bone scans, magnetic resonance imaging (MRI), positron emission tomography (PET) scans, ultrasound and X-ray can all provide non-invasive views into the human body. These views can help to reveal the presence of the tumors that are associated with many different types of cancer.
- Biopsy: A biopsy involves taking a small tissue sample from a suspected cancer. If a cancer is present, analysis of the tissue sample taken will reveal that. For many cancers, a biopsy is the only way to definitively make a diagnosis.
How Is Cancer Prevented?
Because there are many different causes of cancer, there are also many different ways to prevent cancer.
- Eat a Diet Rich in Fruit, Veggies and Whole Grains: Many fruits and veggies are rich in antioxidants, vitamins, minerals, phytochemicals and fiber. Antioxidants, vitamins, minerals and phytochemicals can all prevent and/or repair damaged cells before they can become cancerous. Fiber, which can be found in fruit, vegetables and whole grains can strengthen the muscles around the colon. When muscles around the colon have been strengthened, the colon is stronger and better able to clear cancer causing toxins. Clearing cancer causing toxins before they can damage cells in the colon can help to prevent cancer of the colon.
- Decrease In-take of Refined Sugars and Animal Fats: High calorie and high fat diets have been linked to a number of cancers.
- Limit In-Take of Red Meats and Processed Meats: In-take of processed meats like hot dogs, bacon, ham and deli meats has been linked to cancers of the colon and the rectum. In-take of red meats has been linked to cancers of the colon, rectum, prostate and pancreas.
- Drink In Moderation: Excessive alcohol in-take has been linked to cancers of the liver, kidneys, colon, lungs and breast. So what does it mean to “drink in moderation”? Moderate alcohol use for healthy adult women of all ages means no more than one drink per day. Moderate alcohol use for healthy adult men older than 65 also means no more than one drink per day. For healthy adult men younger than 65 however, moderate alcohol use means no more than two drinks per day. And if you are wondering what exactly “one drink” means? For beer, one drink means 12 fluid ounces. For wine, one drink means 5 fluid ounces. For distilled spirits (80 proof), one drink means 1.5 fluid ounces.
Cancer of the Mouth
- Eating a Mediterranean Diet: Eating the Mediterranean Diet has been shown to lower women’s risk of breast cancer.
- Avoid Tobacco: All forms of tobacco contain cancer causing chemicals (aka carcinogens) that can cause cancers of the lips, tongue, mouth, throat, larynx (voice box), lungs, bladder, kidneys, pancreas and cervix.
- Maintain A Healthy Weight: Maintaining a Body Mass Index (BMI) between 18.5-24.9 decreases a persons risk for a variety of different cancers.
- Exercising Regularly: Exercising regularly has been found to decrease a person’s risk of developing cancers of the esophagus, lungs, kidneys, colon, head and neck, rectum, bladder, and breasts. Regular exercise has also been found to decrease the risk of developing two blood cancers (i.e. myeloma and myeloid leukemia). “Exercising regularly” means getting at least 150 minutes of moderate aerobic activity every week, 75 minutes of vigorous aerobic activity every week or a combination of the two.
- Avoid Excessive Sun Exposure: Excessive sun exposure has been linked to cancers of the skin. Protect yourself from the sun by wearing sunscreen (ideally SPF 30 or higher), avoiding the midday sun from 10AM to 3PM, wearing long sleeves and pants, wearing brimmed hats and wearing sunglasses with UV filters.
- Get immunized: A number of cancers are caused by viruses. These include many cancers of the cervix, penis, vagina, anus, throat and some cancers of the liver. Being immunized against hepatitis B and Human Papillomavirus (HPV) can protect against these cancers.
- Considering Taking Low Dose Aspirin Daily: Taking 81mg of aspirin daily has been found to decrease a person’s risk of colon cancer. Daily aspirin has also been linked to a decreased risk of prostate cancer.
Woman having a screening mammogram
- Avoid Risky Behaviors: Avoiding risky behaviors like having unprotected sex and/or using drugs/sharing needles can decrease the risk of developing cancers of the penis, vulva, vagina, cervix, anus, throat and liver.
- Get Regular Medical Care: Just about all cancers respond better to treatment when they are discovered and treated early. Getting regular medical care that includes routine cancer screenings like mammography, pap smear, colonoscopy, PSA blood testing and complete skin exams can decease a person’s risk of dying from cancers of the breasts, cervix, colon, rectum, prostate and skin.
How Is Cancer Treated?
The goal of any cancer treatment is to destroy and remove the cancer cells present in the body. There are a number of different ways that cancer cells can be destroyed. The approach taken to destroying cancer cells frequently depends on the type of cancer diagnosed and how advanced the cancer is (i.e. the stage of that cancer) at the time of diagnosis. Commonly used approaches include surgery, radiation therapy, chemotherapy, targeted therapy and immunotherapy.
Surgery: The goal of most cancer surgery is to remove as much of a cancer in the body as possible. Additionally, many surgical procedures used to treat cancer are also used to “stage” the cancer, or to determine how advanced the cancer is.
- Radiation Therapy: Radiation therapy is one of the most common treatments for cancer. Radiation therapy uses electromagnetic waves to damage the DNA of cancer cells. Damaging the DNA of cancer cells is intended to kill them. Radiation therapy can be used to cure cancer, to prevent it from spreading further or to treat the symptoms of cancer by shrinking cancer tumors.
- Chemotherapy: Cancer cells rapidly grow and divide. Chemotherapy drugs work by damaging the parts of cells that drive cell growth and division. When cell growth and division is prevented, cells die. Cells that rapidly grow and divide like cancer cells are more susceptible to the chemotherapy medications that interrupt cell growth. Unfortunately, chemotherapy medications target all growing and dividing cells. This means that chemotherapy medications not only kill cancer cells, they also kill healthy normal cells too. It is this fact that leads to many of the “side effects” of chemotherapy (i.e. hair loss, diarrhea, fatigue, etc.).
- Targeted Therapy: Targeted therapy refers to the use of medications that are “targeted” to specific cancers. Each type of cancer cell is unique, having it’s own unique genes and proteins that are specific to it and that are critical to it’s survival. “Targeted” medications target a specific gene and/or protein that is unique to a specific type of cancer cell. By being “targeted” to a specific cancer cell, targeted therapies only kill the cancer cells that they are targeted towards. They do not kill any other cells. This means that, unlike with chemotherapy medications that kill all cell types including healthy cells, targeted medications are not associated with the broad side effects that chemotherapy medications are.
Cancer fighting immune cells
- Immunotherapy: Immunotherapy uses the immune system to fight cancer. The job of the human immune system is to recognize things that can harm the body (i.e. cancer cells, invading bacteria, viruses, parasites, fungi, etc.) and to remove them. Unfortunately, the immune system is not always able to recognize and/or remove harmful cancer cells. Immunotherapy works by either helping the immune system to recognize and then remove cancer cells, or by introducing versions of man-made immune proteins into the body that will then recognize and remove specific cancer cells.