Chemotherapy in adults with cancer.pptx

Chemo

1. Chemotherapy in gyn ecological cancers Roll no 70,71,72

2. Mustard gas used in World War I, was found to have tremendous effect on bone marrow suppression. This led to the concept of cytotoxic chemotherapy in the treatment of human cancer. Objectives of cytotoxic chemotherapy are: Complete remission of the tumor Partial remission (30 percent) with improvement of median survival To prevent recurrence of the tumor To alleviate the symptoms, so as to improve the quality of life (palliation)

3. Effective chemotherapy is designed to kill selectively the malignant cells without producing serious irreversible harm to normal cells. The substances as yet available, damage both cancerous and normal tissues but in contradistinction to normal tissues, cancerous tissues cannot recover from the insult

4. Cell cycle time denotes the amount of time needed by a proliferating cell to progress through the cell cycle and produce a new daughter cell. Cell cycle times vary widely (12-217 hours) but are relatively constant for a specific tumor type.Normal cells have the inherent capacity to multiply and this is controlled by various internal and external forces. There is also constant and balanced cell loss. Normal cells may be classified as: Proliferating cells(bone marrow, intestinal mucosa)—undergo constant cell division. Quiescent cells(liver)—can proliferate under special conditions (injury), otherwise they are in quiescent phase. Static cells (neurons)—rarely proliferat ive

5. Cancer cells undergo uncontrolled and excessive proliferation compared to cell loss. Speed of cell division is the same compared to a normal cell

6. The duration of the cycle from M phase to M phase is called generation time . Dividing tumor cells are most sensitive to cytotoxic agents whereas cells in the G0 are relatively insensitive. C hemotherapeutic drugs are of two varieties depending on the basis of their cell cycle specificity: (a) Cell cycle specific agents which act on proli-ferating cells only. (b) Cell cycle non-specific agents which destroy both resting and cycling cells

7. Drug activity in cell cycle

8. Tumor mass and growth rate. Sensitivity of resting phase cells. Immunocompetence of host cells. Type and dose schedule of agents. (a) Rapidly growing tumors are more amenable than slow growing tumors. (b) A constant fraction of neoplastic cells are killed with each dose of cytotoxic drug. (c) Effect of drugs depends on: (d) High dose intermittent course of chemotherapy may result in high cell kill and optimal destruction of the tumor (dose intensity). Principles

9. (e) Combination agent chemotherapy is superior to single agent therapy for the treatment of most malignancies. (f) Drugs combined, should have synergistic effect, different mechanism of action and different spectrum of toxicity. This will enhance the tumor cell kill and minimize the risk of drug resistance. (g) Drug dose is adjusted according to the tolerance of the patient. Before starting any chemotherapy, pretreatment evaluation should be done