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Surgical Oncology. Definition of Neoplasia. a disorder of cell growth in which there is a permanent and inherited change in cells resulting in a pathological proliferation of tissue. The Etiology of Cancer. Viruses(papilloma, Epstein-Barr, Hepatitis B, retroviruses,HIV) Radiation exposure
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Definition of Neoplasia • a disorder of cell growth in which there is a permanent and inherited change in cells resulting in a pathological proliferation of tissue.
The Etiology of Cancer • Viruses(papilloma, Epstein-Barr, • Hepatitis B, retroviruses,HIV) • Radiation exposure • Environmental industrial carcinogens • Tobacco and alcohol consumption • Genetic susceptibility syndromes
Historical Observation of Chemical Carcinogens • Date Observation Carcinogen • 1761 Excessive use of Nitrosamines • snuff lead to nasal polyps • 1775 Scrotal cancer in soot chimney sweeps • 1860s bladder cancer Aromatic amines • 1915 Rabbit ears painted Benzpyrene • with tar developed • papillomas
Cancer Mortality & Behavior/environmental Factors • Factor Percentage of cancer deaths • Smoking 30 • Diet 30 • Infectious agents 5 • Alcohol 3 • Sedentary lifestyle 3 • Ultraviolet 2 • Air pollution 2
Smoking-related cancers • Lung cancer • Oropharyngeal cancer • Stomach cancer • Cervical cancer • Pancreatic cancer • Renal cancer • Bladder cancer • Liver cancer • Leukemia
Viruses Associated with Cancer • Virus Cancer • Hepatitis B, C Hepatocellular Cancer • HIV Kaposi’s sarcoma • Epstein-Barr virus Nasopharyngeal cancer • Burkitt’s lymphoma • Human Papilloma virus Cervical cancer
Internal causes • Hereditary susceptibility • Endocrine factors • Immune factors
Prevention • First step • etiology • Second step • early detection and treatment • Third step • improve quality of life
Major Genes in Development of Cancer • Oncogenes • Tumor suppressor genes • DNA repair genes
Oncogenes • Growth factors EGF, TGF-α • Growth factor receptors EGFR, PTK • Intracellular transducers cAMP • Transcription factors c-myc
Inactivationof DNA repairgenes Inactivationof Tumor suppressor genes Activationof Oncogenes Tumor Cell
Multi-step nature of Colon Cancer Inactivation of APC TSG • Normal epithelium • Hyperproliferation DNA hypomethylation • Early adenoma Activation of K-ras oncogene • Intermediate adenoma Inactivation of DCC TSG • Late adenoma Inactivation of P53 TSG • Carcinoma
Modern Viewpoint of Cancer as a Long-term Process • Precancerous phase Up to 10~30 years • In-site phase 3~10 years • Invasion phase 1~5 years 1~5 years • Dissemination phase
Nomenclature of Malignant Tumor • Names of tumor Tissue of origin Examples • Carcinoma Epithelium Adenocarcinomas • Sarcoma Mesenchymal Liposarcoma • Malig. lymphoma Lymphocytes Lymphoma • Malig. melanoma Melanocytes Malignant melanoma • Malig. Mesothelioma Mesothelium Pleural malig. Mesothelioma • Teratoma Germ Cells Testicular teratoma • Choriocarcinoma Trophoblast Uterine choriocarcinoma
Benign Tumors • a limited growth potential • the neoplastic cells closely resemble those of the parent tissue ( well diff.) • growing slowly by expansion • a well-encapsulated lesion • do not usually produce serious effect
Malignant Tumors • proliferate rapidly • more poorly differentiated cells • progressive growth and invasion of the surrounding tissues • metastases by lymphatic & blood vessels • if not treated early, eventually cause death
The Degree of Differentiation • Well differentiated • Moderately differentiated • Poorly differentiated
The Objectives of Cancer Staging & Histological Classification • to aid the clinician in planning of treatment • to give some indication of prognosis • to evaluate the efficiency of treatment • to facilitate exchange of information • to assist in continuing clinical studies of cancer
Histopathological Staging & Classification • Adenocarcinomas • Squamous carcinomas • Small cell carcinomas • Large cell carcinomas • Sarcomas Lymphomas • Leukemias Gliomas • Seminomas Teratomas
The Hallmark of Malignancy • Local Destructive Invasion • Distant Metastasis • ------ the cardinal behavior to distinguish benign & malignant tumor
Pathological Features of Malignancy • ● an infiltrative uncapsulated margin • ● invasion of baseline membrane or surrounding structure • ● evidence of invasion of blood vessels or lymphatics or metastases • ● tumor necrosis
Pathological Features of Malignancy • ● architecture abnormalities • e.g. increased gland/stroma ratio • ● cytological abnormalities • e.g. increased nuclear/cytoplasm ratio • ● numerous mitotic figures & abnormal mitoses
Gross Types of Carcinoma Papillary Nodular Ulcerative Stricture Cystic Diffuse Multiple
Two Terms • Metaplasia ---- the replacement of one fully differentiated tissue by another • Carcinoma in situ the histological abnormalities are sufficiently severe to suggest carcinoma , but in the absence of basement membrane invasion
Effects of Malignancy • Tumor arising within a hollow viscus • obstruction • Tumor arising from surface of organ • ulceration and bleeding
Spread of Malignant Tumors • Direct invasion--- Rectal cancer • Lymphatic system to local lymph nodes • -- Breast carcinoma, Gastric cancer • Bloodstream to distant organs • -- Liver, lung & brain • Across body cavities • -- Ovarian carcinoma
Diagnosis • History • Physical Examination • Laboratory Tests • Specific Procedures
Symptomsor Signs of Cancer • Alteration in eating habit • Loss of appetite • Problems in swallowing • Change in bowel habit • The presence of a lump at any site
Symptomsor Signs of Cancer • The appearance of bleeding • Unexplained recurrent pain • Recurrent fevers • Unexplained weight loss • Repeated infections which do not clear with treatment
Para-neoplastic Syndrome • Small cell carcinomas secret ACTH • Cushing’s syndrome Renal carcinomas secret erythropoitin • polycythaemia • Mucin-secreting adenomas increasing the coagulability • thromboembolism
The Diagnostic Procedures of Cancer • History • Family History Individual Habits • Social History Occupation • Marital & Sex History Past History
The Diagnostic Procedures of Cancer • Physical Examination • Systemic • Local • Tumor • Metastatic foci
The Diagnostic Procedures of Cancer • Special Procedures • ● Diagnostic Radiology • Chest X-rays • Barium enema radiography • Gastro-intestinal series radiography • Arteriography • Computerized tomography(CT) • Radioisotope scanning techniques • Mammography • Positron emission tomography(PET)
The Diagnostic Procedures of Cancer • Special Procedures • Ultrasonic examination • Endoscopy • Cytology • Biopsy bone-marrow biopsy • needle biopsy • endoscopic biopsy • Magnetic resonance imagine(MRI)
The Diagnostic Procedures of Cancer • Lab Test • ● Routine test: blood, urine, stool • ● Serum test: enzyme, hormone • glycoprotein, tumor markers • ● Immunology test: AFP, CEA, • tumor-related antigens • ● Flow-cytometry(FCM): DNA ploidy • DNA index • ● Gene Test: Oncogenes, DNA repair gens • Tumor suppressor genes
Tools For Early Clinical Detection • ● Complete physical examination • ● Regular mammography and breast self exam • ● Haemoccult for occult blood in feces • ● Urine analysis and blood count • ● A complete clinical history • ● An in-depth family medical history
Tumor Markers • Tumor marker Examples • Tumor antigens AFP, CEA • Enzymes PSA • Hormones β-HCG • Oncogenes Ras, c-myc,P53 • Tumor associated antigens • CA 19-9,CA-242
TNM staging • T--- primary tumor • N--- regional lymph node • M--- metastases