3. Neoplasia.pdf

Neoplasia/ Pathophysiology of tumors I  Neoplasm –(abnormal mass of tissue) a type of tumor – new growth a www.a  Neoplastic cells don’t obey the law of normal cell growth. V1...

Neoplasia/ Pathophysiology of tumors I  Neoplasm –(abnormal mass of tissue) a type of tumor – new growth a www.a  Neoplastic cells don’t obey the law of normal cell growth. V1 ww.iisii  The study of tumors is called oncology from the Greek word for tumor. I mature, and divide. These are regulated  Cells normally differentiate, grow, processes, balanced in a healthy system.  Any increasejus in tissue size is not necessarily neoplasia. (for example the increase of the left ventricular cardiac hypertrophy in response to an increased pressure load from hypertension). 3  Two major types of neoplasm: l Benign tumors: É Grow slowly, low mitotic rate Well-differentiated Not invasive; well-defined borders Remain localized; do not metastasize Malignant tumors (cancer): I Grow rapidly; high mitotic index. Poorly differentiated. Do not have a capsule. Invade surrounding structures. Can metastasize from the primary to a secondary site (metastasis). 4 Tissue of origin + “-oma” indicates a benign tumor Malignant tumors – use embryonic origin of tissue Carcinomas come from ectoderm and Endoderm - epithelial and glandular tissue Sarcomas arise from mesoderm connective tissue, to muscle, nerve, and endothelial tissues www.i.IE 5 Causes of cancer: Viral causes of cancer: wf f Viruses assoc. with about 15 % of cancers world wide. e.g. viral hepatitis B or C. Bacterial causes: e.g. Helicobacter pylori infects >1/2 world’s population assoc. with B cell lymphomas of the stomach. e Environmental factors: Smoking. Diet. Alcohol up use. Air pollution Occupation hazards Radiation 6  Stage 1 – confined to site of origin Stage 2- cancer is locally invasive Stages of cancer spread: Stage 3 – cancer has spread to regional structures Stage 4- cancer has spread to distant sites 7  Clinical manifestations of cancer I Pain: due to pressure, obstruction, stretching, tissue damage or inflammation, usually late. Fatigue w.SI um a Cachexia – wasting Anorexia mini Early satiety so i Weight loss i i Anemia, Leukopenia and thrombocytopenia. imagine io.me 8  Diagnosis Screening procedures and blood tests: Tumor markers: substances in the blood, spinal fluid or urine ,hormones, genes antigens or antibodies. Tissue biopsy. Radiological tests. 9  Cancer Treatment ok oChemotherapy oRadiation oImmunotherapy oSurgery 10  Side effects of treatment Gastrointestinal tract: Oral ulcers, malabsorption, diarrhea, and vomiting. Bone marrow: to Chemo Rx and radiotherapy suppress bone marrow: decrease in red blood cells, white blood cells, and platelets. Hair and skin: alopecia and skin dryness. Be Reproductive tract: affects gametes, premature menopause. 11 Inflammation and Fever 12  Immunity IT First line of defense Innate resistance : Physical (skin/epithelial layer, GI & Resp Tract) o Mechanical (Cough, sneeze, vomit, cilia action in trachea) to Biochemical barriers (antimicrobial peptides, lung secretions, mucus, saliva, tears, earwax) Second line of defense Inflammation – vascular response – dilation, histamines increase vessel leakage, WBC action, cytokines, fever. Usually redness and heat with swelling. Third line of defense Adaptive (acquired) immunity – antibody production F.SI 13 Inflammation: A non-specific response to injury or necrosis that occurs in a vascularized tissue. Limit and control the inflammatory process Prevent and limit infection and further damage Goals Interact with components of the adaptive immune system Prepare the area of injury for healing 14  Stages of Inflammation 1. Vascular stage go 2. Cellular stage 3. Tissue repair 15 16  Phagocytosis 25815 met um 5 The process by which a cell ingests and disposes of foreign material jan Production of adhesion molecules Margination (pavementing) Adherence of leukocytes to endothelial cells Diapedesis Emigration of cells through the endothelial junctions 17 so 18  Phagocytosis main Opsonization, recognition, and adherence Engulfment EN Steps Phagosome formation Is Fusion with lysosomal granules Destruction of the target 19 20  Phagocytes SW ok Neutrophils (polymorphonuclear leukocyte) Predominate in early (acute) inflammatory responses mi Ingest bacteria, and dead cells. Cells are short lived and become a component of the purulent exudate. 4167 I www.WI 21  Phagocytes Monocytes and macrophages Monocytes are produced in the bone marrow, enter the circulation, and on migrate to the inflammatory site, where they develop into macrophages 22  Phagocytes Eosinophils was 6 Is Mildly phagocytic Against parasites and regulation of vascular mediators when I 84 5 23  Phagocytes Natural killer (NK) cells 4 41 if Function is to recognize and kill cells infected with viruses and cancer cells. 24  Cytokines Interleukins: Produced by macrophages and lymphocytes in response to a pathogen. (fever, pain) Interferon: 961 4146 6 Protects against viral infections produced by virally infected host cells. 25  Local Manifestations of Inflammation Results from vascular changes and corresponding leakage of circulating components into the tissue 4m81 I'm Hotness Redness Swelling Pain Loss of function 26  Fi Exudative Fluids Serous exudate (Watery). Purulent exudate (Pus) in bacterial infection. Hemorrhagic exudate (contains blood). 27  Systemic manifestations of inflammation Fever Caused by exogenous and endogenous pyrogens f Act directly on the hypothalamus Leukocytosis Increased numbers of circulating leukocytes Increased plasma protein synthesis Acute-phase reactants: C-reactive protein, fibrinogen, etc. 28  in Resolution and Repair Regeneration Were Resolution whim Returning injured tissue to the original structure and function Repair Replacement of destroyed tissue with scar tissue Scar tissue composed primarily of collagen 29 At Resolution and Repair Debridement Idioms Cleaning up the dissolved clots, microorganisms, erythrocytes, and dead tissue cells Healing s.im Filling in the wound Sealing the wound (epithelialization) Shrinking the wound (contraction) Chip v55 30  Healing Primary intention Wounds that heal under conditions of minimal tissue loss Secondary intention Wounds that require a great deal more tissue replacement Open wound 31 Dysfunctional Wound Healing 32  Dysfunctional Wound Healing Wound disruption Dehiscence: Wound pulls apart at the suture line due to: Excessive strain and obesity. Increases risk of wound sepsis. iii 33