CM

In-Depth Notes on Cancer

Overview of Cancer

  • Group of diseases characterized by uncontrolled and unregulated growth of cells
  • Can affect individuals of all ages; most diagnoses occur in those over 55 years of age

Statistics

  • Overall decline in cancer incidence and mortality rates
    • Declines noted in lung, colorectal, and laryngeal cancers
    • Increases in other cancer types
  • Higher incidence in men compared to women
  • Cancer is the second leading cause of death in the U.S.
    • Leading cause of death for ages 40 to 79
  • Over 16.9 million Americans are either under treatment, disease-free, or in remission

Case Study: L.M.

  • 18-year-old with a concern about a spot on her back
  • Family history of cancer heightens her worry
  • Important to understand cancer basics for support

Biology of Cancer Development

  • Major dysfunctions in cancer development:
    • Defective cell proliferation (uncontrolled growth)
    • Defective cell differentiation (cells fail to mature properly)

Cell Proliferation

  • Stem cells are undifferentiated cells that mature into specialized cells
  • Cancer cells lose normal regulation and exhibit "contact inhibition" loss:
    • They pile on top of one another
    • Grow indiscriminately and continuously

Cell Cycle Phases

  • Cell Life Cycle Included:
    • G1, S, G2, M (Mitosis)
    • Permanent cells (e.g., neurons) remain in the G0 phase

Genetic Factors in Cancer

  • Two crucial genes involved in cancer mutations:
    • Proto-oncogenes: Promote cell growth; mutations can activate them to oncogenes
    • Tumor suppressor genes: Regulation of cell growth; mutations lead to loss of suppression of tumor growth

Process of Cancer Development

  • Initiation: Mutation of the cell’s genetic structure (e.g., caused by carcinogens)
  • Promotion: Reversible proliferation of altered cells due to exposure to various factors (lifestyle, environmental)
  • Progression: Invasive growth and metastasis occur when cancer cells spread to other locations

Carcinogens and Risk Factors

  • Types of Carcinogens:
    • Chemical (e.g., benzene, formaldehyde)
    • Radiation (e.g., UV associated with skin cancers)
    • Viral (e.g., HPV, Hepatitis B)

Immune Response to Cancer

  • Immune system's role:
    • Detects and destroys cancerous cells via immunologic surveillance
    • Tumor-associated antigens (TAAs) alert the immune system to abnormalities
  • Immunologic escape: Mechanisms allowing cancer cells to evade detection

Classification of Cancer

  • Tumors categorized as benign or malignant
  • Cancer classification includes:
    • Anatomic site (e.g., organ origin)
    • Histology (cell appearance and differentiation quality)
    • Clinical staging (extent of disease progression) based on TNM system

Goals of Cancer Treatment

  • Cure: Aim for complete remission
  • Control: Maintain disease without progression
  • Palliation: Symptom relief and quality of life improvements

Cancer Treatment Modalities

  • Surgery: Remove tumors or perform palliative care
  • Chemotherapy: Use of drugs to kill rapidly dividing cells
  • Radiation Therapy: Target localized areas with radiation
  • Immunotherapy: Boost or modify the immune response against cancer
  • Targeted Therapy: Focus on specific cancer cell pathways or structures
  • Stem Cell Transplantation: Repair or replace damaged bone marrow

Lifestyle Changes for Cancer Prevention

  • Recognize warning signs of cancer
  • Regular screenings and self-exams
  • Healthy lifestyle choices:
    • Balanced diet
    • Regular exercise
    • Limit alcohol consumption
    • Avoid carcinogens (smoking, excessive sun exposure)
  • Importance of maintaining a healthy weight and managing stress

Conclusion

  • Understanding cancer development, treatment options, and prevention strategies is crucial for better health outcomes.
  • Emphasizing education and communication in healthcare settings builds support for individuals affected by cancer.