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.