Biological Basis of Cancer and Multidisciplinary Approach in Cancer Management .pptx

Biological Basis of Cancer and Multidisciplinary Approach in Cancer Management

1. BIOLOGICAL BASIS OF CA NCER AND MULTIPLE DISCIPLINARY AP P ROACH IN CA NCER MANAGEMENT PROF. DR. S.P. GAYATHRE M.S;D.G.O; HEAD OF THE DEPARTMENT DEPARTMENT OF GENERAL SURGERY GOVERNMENT STANLEY MEDICAL COLLEGE

2. WHAT IS CANCER ? Cancer - Greek - Crab Advanced CA surface - Claw like Blood vessels

3. FEATURES OF MALIGNANT CELLS Cancer - Violates normal cellular Cycle Obtain replicative Immortality Evade Apoptosis / Detection / Elimination Acquire Angiogenic Competence Ability to invade Evocation of inflammation Jettison Excess Baggage Ability to change energy metabolism

4. MALIGNANT TRANSFORMATION Two mechanisms 1 ) Genomic instability 2 ) Tumour -related inflammation

5. GROWTH OF A TUMOUR Cancer growth - exponential Early - exponential Late - Plateau

6. IMPLICATIONS OF GOMPERTZIAN GROWTH Majority of growth – Occurs before clinically detectable Time of detection – mostly passed period of rapid growth Time before diagnosis – Cells detach, invade, implant and form metastasis Early tumours – Genetically old, opportunitie s for Mutations Rate of Regression – Depends on its age

7. INHERITED CANCER SYNDROMES AND ETIOLOGICAL FACTORS

8. SCREENING Screening – done in asymptomatic population To improve outcomes at Recognizable early stage Test – Sensitive/Specific, Safe, Inexpensive Done at repeated intervals if disease of insidious onset Benefit must outweigh physical and psychological harm

9. DIAGNOSIS AND CLASSIFICATION Accurate diagnosis is the key to the successful managemen t. An unequivocal diagnosis is the key to an accurate prognosis.

10. INVESTIGATION AND STAGING Staging - Mapping out extent of disease Types : Clinical, Radiological, Histopathological Localised disease - SURGERY/RADIOTHERAPY Extensive disease - Systemic Therapy

11. THERAPEUTIC DECISION MAKING AND THE MULTIDISCIPLINARY TEAM Cancer Mx - Complex - Multidisciplinary interventions required R epresents an attempt - every patient with a particular type of cancer managed appropriately. Not only multidisciplinary but multi professional .

12. PRINCIPLES OF CANCER SURGERY 1) Diagnosis and staging 2) Removal of primary disease. 3) Removal of metastatic disease. 4) Palliation.

13. PRINCIPLES UNDERLYING THE NON SURGICAL TREATMENT OF CANCER The relationship between dose and response and the principle of selective toxicity In contrast to surgery, it is possible to construct dose–response relationships for both the benefits – Also sigmoidal. The practical consequence - a relatively narrow dose range, we move from failure to success, from tolerability to disaster. T heoretically possible to use dose–response curves to calculate an optimal dose for treating each tumour .

14. RADIOTHERAPY

15. FIVE Rs OF RADIOTHERAPY Repair – If sufficient time given between fractional doses, decreased damage to cells; typically 3-6hrs of Half-times Reoxygenation – Hypoxic cells relatively radio resistant. Maybe mitigated if a sequence of daily treatments used. As a result of dying cells more oxygen available to surviving cells Repopulation – Stimulus to rapid proliferation of Tumor cells Redistribution – Sensitivity of cells varies according to cell cycle, synchronized with fractions of radiotherapy to vulnerable phases of tumor cycle Radiosensitivity – Cells derived from tumours differs in their intrinsic sensitivity to radiation

16. CHEMOTHERAPY AND BIOLOGICAL THERAPY Selective toxicity - fundamental principle underlying the use of chemotherapy in clinical practice. The importance of the principle - chemotherapy is rarely sufficient to cure cancer. Chemotherapy is often (in effect, if not in intent) a palliative rather than a curative intervention.

17. PRINCIPLES OF COMBINED TREATMENT Cytotoxic drugs - rarely used as single agents R adiotherapy and chemotherapy are often given together. R ationale - analogous to that used for combined antibiotic therapy , strategy designed to com- bat drug resistance. Three main principles – Basis for choice of drugs for combination therap y (1) use drugs active against the diseases in question; (2) use drugs with distinct modes of action; (3) use drugs with non-overlapping toxicities . By using drugs with different biological effects

18. PALLIATIVE THERAPY Patients fear the symptoms, distress and disruption associated with cancer almost as much as they fear the disease itself. Palliative treatment - goal the relief of symptoms , treating the underlying problem ( as with palliative radiotherapy for bone metastases, sometimes it will not ) If inappropriate to treat the cancer itself - does not imply that there is nothing more to be done, it simply means that there may be better ways to assuage the distress and discomfort caused by the tumor. Palliative medicine in the twenty-first century is about far more than optimal control of pain: its scope is wide, its impact immense

19. END OF LIFE CARE End-of-life care is distinct from palliative care. Patients treated palliatively may survive for many years; E nd-of-life care concerns the last few months of a patient’s life . Many issues, such as symptom control, are common to both palliative care and to end-of-life care but there are also problems which are specific to the sense of approaching death. Includes heightened sense of spiritual need, profound fear and the specific needs of those who are facing bereavement.

20. THANK YOU