cancer

What Is It?
Cancer is a group of diseases characterized by the uncontrolled growth and spread of abnormal cells in the body. Normally, cells grow, divide, and die in an orderly fashion. In cancer, this process breaks down cells that grow uncontrollably, that may invade nearby tissues, and can spread (metastasize) to other parts of the body. There are more than 100 different types of cancer, usually named for the organ or cell type where they originate (e.g., lung cancer, breast cancer, leukemia).

Why It Matters
Cancer is a leading cause of death worldwide. It not only has a profound impact on physical health but also emotional, financial, and social well-being. Many cancers are preventable or treatable, especially when caught early. Education, lifestyle changes, and regular screenings play a powerful role in reducing risk.

Key Facts (At a Glance)

  • Second leading cause of death in the U.S.

  • Estimated 2 million new cases and over 600,000 deaths expected in the U.S. in 2024

  • Most common types: breast, lung, prostate, colorectal, skin (nonmelanoma)

  • Can affect anyone, but risk increases with age

  • Tobacco use, poor diet, obesity, alcohol, sun exposure, and infections (e.g., HPV, hepatitis) are key risk factors

  • Many cancers are staged from 0 (in situ) to IV (metastatic)

How It Affects the Body
Cancer disrupts the body by:

  • Hijacking normal cell cycles, leading to unchecked growth

  • Forming tumors that interfere with organ function

  • Spreading through blood or lymph to other organs (metastasis)

  • Weakening the immune system and causing inflammation
    Effects vary based on cancer type and location, but can include organ failure, hormonal imbalances, nutritional deficiencies, and systemic illness.

Common Symptoms
General signs of cancer include:

  • Unexplained weight loss

  • Persistent fatigue

  • Pain that doesn’t go away

  • Lumps or abnormal growths

  • Changes in skin or moles

  • Unusual bleeding or discharge

  • Chronic cough or voice changes
    Symptoms depend heavily on the cancer type and stage. Some cancers cause no symptoms until advanced stages.

Risks & Side Effects

  • If untreated, cancer can lead to death or severe disability

  • Side effects from cancer or its treatment include:

    • Pain, fatigue, nausea

    • Hair loss, loss of appetite, infections

    • Cognitive changes ("chemo brain")

    • Emotional stress, depression, anxiety

    • Damage to organs from chemotherapy or radiation

  • Cancer survivors often face long-term or late effects of treatment

Who Should Be Cautious

  • Smokers or those exposed to secondhand smoke

  • Individuals with family history of cancer or inherited mutations (e.g., BRCA)

  • People exposed to environmental carcinogens (e.g., asbestos, radon, industrial chemicals)

  • Individuals with poor diet, sedentary lifestyle, or excess body weight

  • People with certain infections (e.g., HPV, hepatitis B/C, H. pylori)

  • Immunocompromised individuals or those with chronic inflammation

When to See a Doctor
Consult a healthcare provider if you:

  • Notice persistent or unexplained symptoms (pain, bleeding, lumps, fatigue)

  • Experience changes in bowel/bladder habits

  • Have family history of cancer and want to assess your risk

  • Need routine screenings (e.g., mammograms, colonoscopies, skin exams)
    Early detection through screening saves lives and increases treatment options.

Related Conditions / Interactions

  • Some conditions increase cancer risk, including:

    • Chronic inflammation (e.g., ulcerative colitis → colon cancer)

    • Obesity and type 2 diabetes

    • Autoimmune diseases

  • Cancer can affect or be affected by:

    • Blood clotting disorders

    • Immune function

    • Mental health due to the psychological impact of diagnosis and treatment

    • Interactions with medications, including chemo interactions with other prescriptions

Last Updated: June 16, 2025