What is Cancer?
Cancer is the name given to a set of more than 100 diseases that have in common the disordered growth of cells that invade the tissues and organs and can spread to other regions of the body. Healthy cells multiply when necessary and die when the body no longer needs them. Cancer occurs when the body's cells increase is out of control, and they divide very fast. It can also occur when the cell "forgets" to die.
Dividing rapidly, these cells tend to be very aggressive and uncontrollable, determining the formation of tumors or malignant neoplasms. On the other hand, a benign tumor simply means a localized mass of cells that multiply slowly and resemble their original tissue, rarely constituting a risk of death.
Cancer is caused by changes (mutations) inside the cells. The DNA inside a cell contains a set of instructions that tell the cell how to grow and divide. Errors in the instructions can allow a cell to become cancerous. The gene mutation can instruct a healthy cell to:
- Allow for rapid growth: the gene mutation can tell a cell to grow and divide faster. This creates many new cells with the same mutation
- Prevent cell growth from stopping: normal cells know when to stop growing, so you have just the right number of each type of cell. Cancer cells may lose control when they stop growing
- Making mistakes when fixing DNA errors: repair genes look for errors in a cell's DNA and make corrections. A mutation in this repair gene may mean that other errors will not be corrected, leading to the cells becoming cancerous.
These mutations are the most commonly found in cancer. But many other genetic mutations may contribute. Genetic mutations can occur for several reasons, for example:
- Congenital: You can be born with a genetic mutation that you inherited from your parents. This type of mutation is responsible for a small percentage of cancers
- Genetic mutations that occur after birth: Most genetic mutations occur after you are born and are not inherited. A number of factors can cause genetic mutations such as smoking , radiation, exposure to viruses, cancer-causing chemicals (carcinogens), obesity , hormones, chronic inflammation, and lack of exercise.
Genetic mutations with which we are born and those that you acquire throughout your life can work together to cause cancer. For example, if you inherited a genetic mutation that predisposes you to cancer, that does not mean that you will have cancer for sure. Instead, you may need one or more genetic mutations that cause cancer. Your hereditary genetic mutation makes you more vulnerable to cancer than other people when exposed to a particular risk factor.
It is not clear how many mutations must be accumulated for cancer to form. This is likely to vary among cancers.
Cancer can take decades to develop. That is why most people are diagnosed with cancer at age 65 or older. Although it is more common in older adults, not a disease exclusively in this age group - it can be diagnosed at any age.
Certain lifestyle choices are known to increase the risk. Smoking, drinking more than one drink a day (for women of all ages and people over 65 years) or two drinks per day (for men under 65 years), excessive sun exposure or frequent burns, obesity and having unprotected sex may contribute to cancer.
You can change these habits to reduce the risk of cancer - although some habits are easier to change than others.
Only a small part of the cancers happens due to an inherited condition. If common in your family, it is possible that mutations are being passed from one generation to the next. You may be a candidate for genetic testing to see if you have mutations that may increase the risk of certain hereditary cancers. Keep in mind that having an inherited genetic mutation does not necessarily mean that you will get cancer.
Some chronic health problems, such as ulcerative colitis, can significantly increase the risk of developing certain types of cancer. Talk to your doctor about your risk. Other diseases like HPV and hepatitis B can also increase this risk.
The environment around you may contain harmful chemicals that may increase the risk of cancer. Even if you do not smoke, you can inhale the secondhand smoke people are smoking. Chemicals in your home or workplace, such as asbestos and benzene, are also associated with an increased risk of cancer. Excessive pollution is also linked to increased chances of cancer.
Symptoms of Cancer:
The signs and symptoms caused by cancer vary depending on which part of the body is affected. Some general signs and symptoms that are not cancer specific and should be crossed with other risk factors include:
- Lump or thickening area that can be felt under the skin
- Weight changes, including unintentional loss or gain
- Skin changes such as yellowing, darkening or redness of the skin, wounds that do not heal or soft changes
- Changes in bowel or bladder habits
- Persistent cough
- Difficulty in swallowing
- Persistent indigestion or discomfort after eating
- Persistent or unexplained muscle or joint pain
- Persistent night sweats or sweats for no apparent reason.
When to see a doctor
Make an appointment with your doctor if you have any persistent signs or symptoms for no apparent reason. If you do not have any signs or symptoms but are worried about the risk of cancer, talk about your concerns with your doctor. Ask about which cancer screening exams and procedures are right for you.