Lecture: Overview of Cancer and Antineoplastic Drugs

Key Definitions

• Analogue: Chemical compound similar to another but differing in some components.
• Anaplasia: Lack of cellular differentiation critical for normal growth.
• Antineoplastic Drugs: Used to treat cancer; also known as chemotherapy.
• Benign: Noncancerous neoplasm, not life-threatening.
• Cancer: Malignant neoplastic disease, potentially fatal.
• Carcinogen: Substance or organism that causes cancer.
• Carcinomas: Malignant epithelial neoplasms, capable of invading tissue and metastasizing.
• Cell Cycle-Specific/Nonspecific Drugs: Drugs that act on specific phases or any phase of the cell cycle, respectively.

Cancer Overview

• Broad term for diseases characterized by uncontrolled cell growth and potential spread (metastasis).
• Lacks growth control mechanisms and differentiation seen in normal cells.
• Can metastasize via blood or lymphatic system.

Tumor Characteristics

• Benign vs Malignant:
  • Benign: Non-invasive, usually harmless, but can be lethal if it disrupts critical functions.
  • Malignant: Invasive, capable of metastasis, unpredictable growth.

Types of Tumors

• Carcinomas: From epithelial tissue (e.g., skin, lining of organs).
• Sarcomas: From connective tissue (e.g., bone, muscle).
• Lymphomas: From lymphatic tissue.
• Leukemias: From blood-forming tissues, circulate through blood and lymph.

Cancer Etiology

• Age, genetic, ethnic factors, oncogenic viruses, environmental factors contribute to cancer risk.
• Examples: HPV linked to cervical cancer; Epstein-Barr virus linked to lymphoma.

Antineoplastic Drugs

• Cell Cycle-Specific: Effective during certain cell cycle phases.
• Cell Cycle-Nonspecific: Effective any time during the cell cycle.
• Drugs have a low therapeutic index, often toxic.
• Common adverse effects: Hair loss, nausea, vomiting, bone marrow suppression.

Drug Classes

• Antimetabolites: Interfere with DNA/RNA synthesis (e.g., Methotrexate).
• Mitotic Inhibitors: Prevent cell division (e.g., Paclitaxel).
• Topoisomerase Inhibitors: Interfere with DNA replication (e.g., Topotecan).
• Antineoplastic Enzymes: Interfere with cancer cell metabolism (e.g., Asparaginase).

Chemotherapy Considerations

• Goal: Kill every neoplastic cell or control cancer growth.
• Combination regimens often used for effectiveness.
• Monitoring required: Blood cell counts, managing side effects.

Patient Management

• Address treatment side effects: Hair loss, nausea, fatigue.
• Manage risk for infections due to bone marrow suppression.
• Consider patient’s cultural, emotional, financial needs.

Advances in Treatment

• Targeted Drug Therapy: Drugs specifically target cancer cell growth mechanisms, sparing normal cells.
• TKIs (Tyrosine Kinase Inhibitors): Used for specific cancers (e.g., lung, breast).

Conclusion

• Cancer treatment is complex, involving multiple drug classes and approaches.
• Effective management requires understanding drug mechanisms, patient care needs, and ongoing research developments.