Cancer is a very serious group of diseases that can affect nearly any part of the body. Cancer occurs when cells in the body start to grow out of control, forming tumors or invading other parts of the body. While some cancers may grow slowly, the majority can spread quickly to other areas if not treated in time. That’s why early detection and treatment are so important for improving outcomes.
What is cancer?
Cancer refers to a large group of diseases characterized by uncontrolled cell growth. Normal healthy cells in the body grow, divide, and eventually die off in an orderly fashion. Cancer cells, however, lose the ability to properly regulate this process. As a result, they continue dividing and forming new abnormal cells that invade areas where they do not belong.
There are over 100 different types of cancer that can arise in almost any tissue or organ. Some of the most common cancers include:
- Breast cancer
- Lung cancer
- Colorectal cancer
- Prostate cancer
- Skin cancer
Cancers are usually named for the part of the body where they originate. For example, colon cancer arises originally in the colon. However, many cancers can eventually spread (metastasize) to other areas if not caught early enough.
What causes cancer?
Cancer is caused by changes to the DNA inside of cells. DNA provides the instructions for all cell activities and functions. When the DNA code becomes damaged or changed, this can lead cells to grow and reproduce uncontrollably.
There are a number of factors that can contribute to DNA changes and result in cancer development:
- Genetics: Some people inherit genetic mutations from parents that increase cancer risk.
- Lifestyle factors: Behaviors like smoking, heavy alcohol use, poor diet, and physical inactivity are linked to increased cancer risk.
- Environmental exposures: Carcinogens in the environment such as UV radiation, radon gas, asbestos may damage DNA over time.
- Viruses and bacteria: Infections from certain viruses and bacteria are associated with several cancer types.
- Age: Cancer risk tends to increase as people get older, likely due to DNA changes that accumulate over time.
Why are cancers serious?
Cancer is very serious because of its ability to invade and spread to vital organs. As cancer cells multiply, they can interfere with the normal functioning of tissues and organs. Some key reasons cancers can be life-threatening include:
- Damage to vital organs: Cancers like lung, liver, and pancreatic cancer often grow in essential organs. As the cancer enlarges, it impairs the organ’s ability to function properly.
- Weakening of bone: Bone cancers can weaken bones, making them more susceptible to fractures.
- Spread to brain: Advanced cancers can metastasize to the brain, causing neurological impairments.
- Blockage of airway: Lung tumors or enlarged lymph nodes can restrict breathing by narrowing the airways.
- Bleeding problems: Leukemias and other blood cancers can impede the blood’s ability to clot.
In addition to physical effects, cancers that continue to advance and spread also become much more difficult to treat. The earlier cancer is detected, the better the odds that treatment will be successful.
How do cancers spread in the body?
One of the most dangerous qualities of cancer cells is their ability to invade into surrounding tissue and spread to other areas in a process called metastasis. There are a few different ways cancers can metastasize:
- Direct invasion: Cancer cells push into nearby normal tissues.
- Lymph system: Cancer cells can enter lymph vessels and follow lymph drainage pathways to reach distant sites.
- Bloodstream: Cancer cells may break off into the bloodstream to travel to other organs.
For example, a breast cancer may first invade nearby muscle tissue, get into lymph nodes, and then metastasize down the lymph system and bloodstream to the bones, lungs, liver, and brain. Metastatic cancer can be very challenging to treat effectively.
What are the common signs and symptoms of cancer?
Signs and symptoms of cancer depend on the type and location of the cancer. Some general indications of the disease include:
- Unexplained weight loss
- Fever
- Fatigue
- Skin changes such as yellowing, darkening or redness, sores that won’t heal
- Changes in bowel or bladder function
- Persistent cough or trouble breathing
- Hoarseness
- Difficulty swallowing
- Unusual bleeding or discharge
- Thickening or lump in the breast, testicles or elsewhere
- Indigestion or difficulty swallowing
- Obvious change in a wart or mole
- Nagging cough or hoarseness
Of course, many of these symptoms can be caused by other benign conditions. That’s why it’s important to see your doctor and get checked out if any persist. Catching cancer early on greatly improves prognosis.
What are the treatment options for cancer?
Doctors utilize a wide range of cancer treatments including:
- Surgery – Operation to remove tumors from the body.
- Chemotherapy – Using cytotoxic drugs to kill cancer cells.
- Radiation – Using high-energy beams to destroy cancer tissue.
- Immunotherapy – Drugs that help the immune system attack cancer cells.
- Targeted therapies – Medications that specifically target cancer molecular or genetic traits.
- Hormone therapy – Blocks or suppresses hormones that can fuel cancer growth.
- Stem cell transplant – Restores blood-forming stem cells destroyed during cancer treatment.
Doctors may use one or a combination of these options. The specific treatments recommended for an individual patient depends on the cancer type, stage, genetics, and other factors.
What are the survival rates for common cancers?
Survival rates give a general indication of prognosis, or outlook for recovery. But these are estimates based on large groups of patients. Each person’s situation is different, so discuss your individual prognosis with your doctor.
Here are 5-year relative survival rates for some of the most common cancer types:
| Cancer Type | 5-Year Relative Survival Rate |
|---|---|
| Breast (female) | 90% |
| Colorectal | 64% |
| Lung | 18% |
| Prostate | 98% |
| Melanoma | 92% |
These statistics demonstrate that certain cancers have a much better prognosis when detected and treated early. Lung cancer in particular often goes undetected until later stages when survival chances are low. Screening and early diagnosis makes a major difference.
Can cancer be prevented?
While some risk factors for cancer like genetics cannot be controlled, there are steps you can take to lower your overall chance of developing the disease:
- Get screened regularly – Screening tests can detect cancers early when they are most treatable.
- Maintain a healthy weight – Obesity raises the risk for several cancers.
- Exercise regularly – Physical activity is linked to lower cancer risk.
- Don’t smoke – Smoking accounts for the majority of lung cancer deaths.
- Eat a healthy diet – Emphasize plant foods and limit processed meats.
- Limit alcohol – Heavy drinking is tied to several cancers.
- Protect your skin – Use sunscreen and avoid excessive UV radiation.
- Get vaccinated – Hepatitis B and HPV vaccines reduce risk of associated cancers.
Making healthy lifestyle choices offers the best protection against developing cancer over the long term. Genetics and other factors outside of your control will always play some role, but being proactive stacks the odds in your favor.
Conclusion
Cancer comprises many different diseases, but they share the common trait of uncontrolled cell growth that can invade and damage essential body systems. Major advances are being made in cancer treatment, but early detection and intervention remain critical for boosting survival chances. Many cancers can be prevented by maintaining a healthy lifestyle and getting recommended screening tests. While a cancer diagnosis is always concerning, the outlook for many patients continues to improve.
Key Points:
- Cancer cells proliferate uncontrollably and can damage vital organs.
- Cancer has the ability to spread throughout the body, or metastasize.
- Symptoms depend on cancer type but may include weight loss, fatigue, cough, or skin changes.
- Common treatments include surgery, chemotherapy, radiation therapy, immunotherapy.
- Early detection via screening offers the best chance for survival.
- Healthy lifestyle choices can help prevent many cancers.