Cancer is a disease in which abnormal cells divide uncontrollably and destroy body tissue or spread to other parts of the body. Cancer can start almost anywhere in the human body, which is made up of trillions of cells. Normally, human cells grow and multiply to form new cells as the body needs them. When cells grow old or become damaged, they die, and new cells take their place. Sometimes this orderly process breaks down, and abnormal or damaged cells grow and multiply when they shouldn’t. These cells may form tumors, which are lumps of tissue. Tumors can be cancerous or not cancerous.

Types of cancer

• Carcinoma

This cancer begins in the skin or in tissues that line or cover internal organs. There are different subtypes, including adenocarcinoma, basal cell carcinoma, squamous cell carcinoma and transitional cell carcinoma.

• Sarcoma

This cancer begins in the connective or supportive tissues such as bone, cartilage, fat, muscle or blood vessels.

• Leukaemia

This is cancer of the white blood cells. It starts in the tissues that make blood cells such as the bone marrow.

• Lymphoma and Myeloma

These cancers begin in the cells of the immune system.

• Brain and Spinal cord cancers

These are known as central nervous system cancers.

Risk Factors

• Age (Growing Risk with Age)

Cancer risk increases as you get older because the body’s repair mechanisms become less efficient over time. Most cases are seen after middle age, but younger individuals may still be at risk depending on other factors and exposures.

• Family History

Having close relatives with cancer may increase your personal risk. Some cancers are linked to inherited gene changes. Knowing your family history helps you stay more alert to early signs and consider timely screening if needed.

• Long-Term Tobacco Exposure

People with a history of smoking or tobacco use carry a higher lifetime risk of developing cancer. The risk builds gradually over years. Even passive exposure (secondhand smoke) over time can increase susceptibility.

• Chronic Lifestyle Patterns

Long-term habits like poor diet, low physical activity, and ongoing weight gain can increase vulnerability. These patterns affect body balance over time. It’s not about occasional habits, but consistent lifestyle over years that influences risk.

• Alcohol Over Time

Regular alcohol consumption over the years can increase the likelihood of certain cancers. Risk is linked to both frequency and quantity.

• Repeated Sun Exposure

Frequent and unprotected exposure to strong sunlight over years increases the risk of skin-related cancers. This risk is higher in people with sensitive skin.

• Chronic Infections History

People with long-standing infections like HPV or hepatitis have a higher chance of developing certain cancers later in life.

• Occupational & Environmental Exposure

Working in environments with chemicals, dust, or toxins over long periods can increase cancer risk. This risk often develops slowly and may not be noticeable until years later.

Prevention

• Avoid Tobacco Completely

Quitting smoking and avoiding all forms of tobacco is one of the most effective ways to reduce cancer risk. The benefits start early and continue to improve over time. Even reducing exposure to secondhand smoke makes a meaningful difference in long-term health.

• Healthy Lifestyle Choices

Staying physically active and maintaining a healthy weight helps regulate body functions and lowers cancer risk. Small daily habits can have a big impact over time. Regular exercise also improves immunity and overall well-being.

• Balanced Diet

Eating a diet rich in fruits, vegetables, and whole foods supports the body’s natural defense system. Nutrients and antioxidants help protect cells from damage. Limiting processed and junk food can further reduce long-term risk.

• Limit Alcohol Intake

Reducing or avoiding alcohol lowers the risk of several cancers. The less you consume, the lower your risk becomes.

• Sun Protection

Protecting your skin from excessive sun exposure reduces the risk of skin cancer. Using sunscreen and avoiding peak sunlight hours is important.

• Vaccination (If Applicable)

Vaccines like HPV and hepatitis B can prevent infections that are linked to certain cancers. This is a powerful preventive step in eligible individuals.

• Regular Screening

Routine health check-ups and screenings help detect cancer early, even before symptoms appear. Early detection greatly improves treatment outcomes.

Tests

• Biopsy (Confirming Cancer)

A biopsy involves taking a small sample of tissue to check for cancer cells. It is the most definitive way to confirm cancer. The sample is examined under a microscope to determine the type of cancer and how aggressive it is, which helps guide treatment decisions.

• Imaging Scans (CT, MRI, PET)

Scans are used to detect tumors, understand their size, and check if cancer has spread. Different scans provide different levels of detail. They are also used during and after treatment to monitor progress and response.

• Blood Tests

Blood tests help assess overall health and may detect markers linked to certain cancers. They are commonly used alongside other tests. They also help monitor how the body is responding to treatment over time.

• Tumor Markers

These are specific substances found in blood that may be elevated in some cancers. They are not used alone for diagnosis but help in monitoring. Changes in levels over time can indicate how well treatment is working or if cancer is recurring.

• Endoscopy Procedures

This involves using a thin tube with a camera to examine internal organs like the stomach, lungs, or colon. It helps detect abnormal growths directly.

• Genetic Testing

Genetic tests identify inherited mutations that may increase cancer risk. They are useful for people with a strong family history. This helps in planning early screening and preventive strategies.

• Screening Tests (Routine Checks)

Tests like mammograms, Pap smears, or colon screening help detect cancer early, often before symptoms appear. Early detection improves outcomes significantly.

FAQs

• Is cancer always life-threatening?

Not always. Many cancers can be treated successfully, especially when detected early. Survival rates have improved significantly with modern treatments. The outcome depends on the type, stage, and how early it is diagnosed, so timely care makes a big difference.

• Can cancer be cured?

Some cancers can be completely cured, while others can be controlled for a long time. Early-stage cancers have a higher chance of cure. Even in advanced cases, treatment can help improve quality of life and extend survival.

• Early Signs ?

Symptoms can vary, but common signs include unexplained weight loss, unusual lumps, persistent pain, or changes in normal body functions. It’s important not to ignore ongoing or unusual symptoms and seek medical advice when needed.

• Does cancer spread quickly?

It depends on the type of cancer. Some grow slowly, while others can spread faster if not treated. Early detection helps control the spread.

• Can young people get cancer?

Yes, although cancer is more common in older adults, it can occur at any age. Certain types are more common in younger individuals.

• Is cancer contagious?

No, cancer does not spread from one person to another through contact or daily interaction.

• Can lifestyle changes reduce cancer risk?

Yes, healthy habits like balanced diet, exercise, and avoiding tobacco can significantly lower the risk over time.

• Is cancer treatment very painful?

Treatment may have side effects, but pain and discomfort are usually manageable with proper care and support.

• Can stress cause cancer?

Stress alone does not directly cause cancer, but long-term stress can affect overall health and indirectly impact risk.

• Do all tumors mean cancer?

No, not all tumors are cancerous. Some are benign (non-cancerous) and do not spread to other parts of the body.

How is cancer stage determined?

• Healthcare providers use cancer staging systems to plan treatment and develop a prognosis or expected outcome. TNM is the most widely used cancer staging system. T stands for primary tumor. N stands for lymph nodes and indicates whether a tumor has spread to your lymph nodes. M stands for metastasis, when cancer spreads.

• Doctors check how large the primary tumor is and how deep it has grown into nearby tissues.

• They see whether cancer has spread to nearby lymph nodes and how many are affected.

• This checks if cancer has spread to distant organs like lungs, liver, or bones.

• Based on TNM results: Stage 0 ? Very early, localized Stage 1–2 ? Limited spread Stage 3 ? Advanced local spread Stage 4 ? Distant spread (metastatic)

How Does Cancer Develop?

• Cancer is a genetic disease—that is, it is caused by changes to genes that control the way our cells function, especially how they grow and divide. Genetic changes that cause cancer can happen because: of errors that occur as cells divide. of damage to DNA caused by harmful substances in the environment, such as the chemicals in tobacco smoke and ultraviolet rays from the sun. (Our Cancer Causes and Prevention section has more information.) they were inherited from our parents. The body normally eliminates cells with damaged DNA before they turn cancerous. But the body’s ability to do so goes down as we age. This is part of the reason why there is a higher risk of cancer later in life. Each person’s cancer has a unique combination of genetic changes. As the cancer continues to grow, additional changes will occur. Even within the same tumor, different cells may have different genetic changes.

• Cancer starts when DNA in a cell gets damaged or mutated, affecting normal cell functions.

• Mutated cells begin to grow and divide rapidly without following the body’s control signals.

• These abnormal cells accumulate and form a mass called a tumor (benign or malignant).

• Cancer cells spread into surrounding healthy tissues, damaging normal body functions.

• Cancer cells can travel through blood or lymph and form new tumors in other organs.