Final Topic List Flashcards

Question

**Repair vs Regeneration**

Answer 1

* Definition – A complex process in which the skin, and the tissues under it, repair themselves after injury * Stages * 1.Inflammatory phase (up to 3d after injury) - Clot formation, ↑ vessel permeability, neutrophil migration * 2.Proliferative (day 3–weeks after injury) - Deposition of granulation tissue and type III collagen, angiogenesis, epithelial cell proliferation * 3.Remodeling (1 week–6+ months after injury) of collagen to ↑ tensile strength of tissue * Intentions * Regeneration (Primary healing) – Replacement of dead cells by proliferation of cells of same type – involves cell growth & differentiation and cell-matrix reactions – requires intact basement membrane. Occurs with clean wounds with little tissue damage and adjacent surfaces closely together. Examples - Surgical suture, muscle fiber damage. * Repair (Secondary healing) – Replacement of injured tissue w/fibrous scar, NOT w/parenchymatous tissue of same kind. Occurs in large tissue defect /Suture impossible / Intense inflammatory response -\> Longer healing. * Examples - Large surface ulcers and open wounds * Interruptions * Foreign body/material, Infection – continued tissue damage * Ischemia, Diabetes, Obesity, Old age * Malnutrition (Vit. C- scurvy, Zinc, water)

Answer 2

* Most important indicator of prognosis and therapy of malignant tumor. * Helps to calculate 5-year survival rate * Grading * Definition – Degree of cellular differentiation and mitotic activity of malignant tumor cells as seen on histology, relative to tissue of origin. * Ranges from low grade (G1. well-differentiated) to high grade (G4. poorly differentiated, undifferentiated, or anaplastic) * ↑ Grades -\> ↑ Response to chemo/radiotherapy (but also more aggressive) * Staging * Definition – Clinical/pathological assessment of the degree of localization/spread of malignancy * Advanced stage → Require agressive treatment * Staging (TNM) * T – Primary Tumor Size and Local extent (Depth, invasiveness level). T1-T4 * T0 -\> in-situ lesion * N – Regional lymph Node involvement. N0-2 (no nodes, local, distant) * M – Metastases. M0,1 (No metastasis, yes metastasis)

Answer 3

* % of people in a study or treatment group who are alive 5 yrs after they were diagnosed with or started treatment for a disease, such as cancer; survival rate for estimating the prognosis * Normally calculated from point of diagnosis * Not used in leukemia & lymphoma (upto 12 months survival) * Depends on: * Stage first diagnosed * Treatment possibility * Examples: * Breast Cancer - 70% * Osteosarcoma - 60% * Leiomyosarcoma - 40% * Lung Carcinoma - 10% * Pancreas Carcinoma - 1.8% * Hodgkin's Lymphoma: 70-90%

Answer 4

* Definition – The hallmark of cancer. Tumor cells that grow in one location, spread to a distant location and implanted there. * Spreading routes: * Local spread * Vascular/lymphatic- most common * CSF space- less common * Contact seeding * Abnormal cavities (pleural/peritoneal) * Common sites of metastasis: * Brain- 1 degree tumor is most common originating: Lung \> breast \> melanoma, colon, kidney. * Liver- originating: Colon \>\> Stomach \> Pancreas * Bone- originating: Prostate, Breast \> Kidney, Thyroid, Lung

Answer 5

* Definition – Irreversible severe dysplasia that involves the entire thickness of epithelium but does not penetrate the intact basement membrane * Represents the early stage of neoplasia, Pre-invasive Neoplasm * The abnormal neoplastic cells grow in their normal place * Synonyms: * Grade 0 * Pre-invasive * Intraepithelial * Morphology – May share cytological features with malignancy * Outcomes – Early detection and treatment usually successful * Examples: * Cervical Squamous-cell Carcinoma In-Situ * Bronchioloalveolar carcinoma- the only form of CIS that can kill directly

Answer 6

* Viral Oncogenesis. ↑ oncogenes (gain of function) → Neoplasia * HPV (subtypes 16, 18, 31, 33) → (SCC) of vulva, vagina, anus, cervix and (cervical adenocarcinoma) * EBV → Burkitt/Hodgkin Lymphoma, nasopharyngeal carcinoma * HBV, HCV → Hepatocellular Carcinoma (70-85% cases) * HTLV-1/ Human T-lymphotropic virus -\> Adult T-cell leukemia/ lymphoma * HHV-8 (Human Herpes Virus) - Kaposi sarcoma * Merkel Cell virus -\> Merkel Cell carcinoma (very rare) * H. Pylori -\> Gastric Adenocarcinoma & Gastric Lymphomas (b cell origin)

Answer 7

* Definition – Closely resemble tissue of origin (fully differentiated) * Slow Growth * Well demarcated – Margins well defined. Encapsulated * No Metastases! * Complications * Compression of adjacent tissues * Blockage of lumen * Endocrine functions * Examples “-oma” * Lipoma- adipose tissue * Fibroma- connective tissue * Adenoma- glandular epithelium and their surrounding connective tissue. * Papilloma- surface epithelium (skin, larynx, tongue) * Non-neoplastic examples * Choristoma- Growth of normal tissue in an abnormal location * Hamartoma- disorganized, tumor-like overgrowth of cell types regularly found within an affected organ

Answer 8

* Definition – Neoplasm with tendency to become worse * Grow fast * Margins poorly defined - Not encapsulated * Invasive and Metastasize (Through Lymph, Blood, Cavities) * Classification * Well-Differentiated – Constituent cells closely resemble tissue of origin * Poorly-Differentiated – Little resemblance to tissue of origin * More aggressive. Atypical cytology (cell features) * Anaplastic – Impossible to identify cell of origin. The hallmark of malignancy * Complications * Invasiveness – Growth and destruction of adjacent tissues * Metastasis – Cells from primary tumor become detached  Migrate  Grow as separate mass. Usually cause tissue destruction. Spreading routes * Local spread, Vascular/lymphatic * CSF space- less common. Contact seeding * Abnormal cavities (pleura etc.) * Treatment – Chemotherapy, Radiation, Surgery * Examples – Sarcoma, Carcinoma, Teratoma

Answer 9

* Mesenchymal -\> Sarcoma * Epithelial -\> Carcinoma * Glial -\> Astrocytoma * Skin -\> Melanoma * Lymphatic -\> Lymphoma

Answer 10

* Definition – An area of collapsed or non-expanded lung (reduced volume of lung tissue). * It is reversible, but areas of atelectasis predispose for infection due to decreased mucociliary clearance. * Risk – Bedridden patients * Types * Obstruction/resorption - Airway obstruction prevents new air from reaching distal airways; examples include foreign body, COPD, mucus plug, and tumor * Compression - External compression on lung→↓lung volumes: fluid/ blood, air, tumor in the pleural space. * Can caused by car accident (→pneumothorax, blood, etc.) * Mediastinum shift- if on one side only * Contraction (scar) - Due to fibrosis and scarring of the lung. * Adhesive (patchy) - Due to a lack of surfactant (not loss of it!), seen in NRDS in premature babies and ARDS in adults.

Answer 11

* Definition – Destruction of alveolar septa results in enlarged air spaces (↓gas exchange area) and a loss of elastic recoil. * Causes - Smoking, α1-AT deficiency (congenital/smoking), artificial ventilation, coal mining, diving * Symptoms – Dyspnea, barrel chest, cyanosis, hypercapnia and respiratory acidosis. * A characteristic tripod sitting posture * Hyper-resonant percussion notes; diminished breath sounds on auscultation * Types – By anatomical distribution of the septal damage: * Centriacinar (Centrilobular)- The most common form. Damaged and dilated respiratory bronchioles. Caused by smoking/air pollution → chronic bronchitis and inflammation. Seen in upper lobes. Apical blebs and bullae may be seen. * Panacinar (Panlobular)- Affects the entire acinus. Caused by α1-antitrypsin deficiency. Seen at the lower lobes. * Paraseptal (Distal acinar)- Unknown cause. Extension to the pleura causes pneumothorax, fibrosis, scarring and atelectasis. * Irregular- post-inflammatory scarring involves the acinus in an irregular distribution. * Complications – Chronic bronchitis, Pneumothorax, Cor Pulmonale, right heart failure

Answer 12

* Epidemiology – The leading cause of cancer death * 5 Year Survival – 10% * Etiologies * Tobacco smoking * Industrial hazards [Coal, Uranium, Radiation, Asbestos, Arsenic, and Mustard gas * Air Pollution – Radon * Genetic factors – ↓Tumor Suppressor Genes * Scarring – Adenocarcinomas * Classification * Adenocarcinoma(38%)-invasive with glandular differentiation. Women, non-smokers. Periphery. Good prognosis * Preceded by Atypical adenomatous hyperplasia \> Adenocarcinoma in situ * Patterns: Acinar, Lepidic, Papillary/ Micropapillary, Solid * Squamous cell carcinoma (20%) – Men, smoker. Centrally- main bronchi/entire lobe. Grows fast, metastasize late * Progresses from metaplasia →CIS→invasive CA. * Paraneoplastic syndrome may occur. * Small Cell (Oat Cell) Carcinoma (14%)- Prognosis – 6 months. Males, smokers. Late diagnosis. Center/periphery. * Paraneoplastic syndrome very common. * Large Cell Carcinoma (3%). Smoking! Diagnosis by exclusion other types. Periphery, poor prognosis * Mesothelioma – Rare, arise from mesothelium layer that covers the lung/many internal organs. Poor prognosis * Asbestos exposure 90% of cases (latent period of 15-20years). Not associated w/smoking!!! Causes lung fibrosis, recurrent pleural effusions and may compress the lungs

Answer 13

* Definition – Consolidation of the entire lobe (usually the lower [LOWbar]) or the whole lung. * Characterized by acute inflammatory intra-alveolar exudate * More often in adults * Causative organisms * Strep Pneumonia- most frequently. Community acquired * Klebsiella – Alcoholics * Legionella (\<5%) * Haemophilus Influenza – Children, Elderly (60+), COPD * Mycobacterium Tuberculosis * Stages (Congestion -\> Red Hepatization -\> Gray Hepatization -\> Resolution) * Congestion – Vascular hyperemia, intra-alveolar fluid and edema * Red Hepatization - Most people die here * Neutrophils, RBCs and fibrin filling the alveolar spaces * Liver-like consistency of lobe – Firm and airless * Grey Hepatization - Progressive disintegration of RBC * Resolution- Healing. Exudate is coughed up, digested or ingested * Signs and Symptoms * Fever, Cough, Dyspnea, Malaise * Chest pain and Hemoptysis * Radiology – Lobar alveolar filling

Answer 14

* Definition – Chronic granulomatous inflammation caused by Mycobacterium Tuberculosis * Location – Most common is lungs (Through sputum and inhalation). Also can be in GI * Symptoms - Fever, Night sweat, Weight loss, Chronic cough, Hemoptysis * Types * Primary TB - Initial infection (in non-sensitized host), Lower lobes. * Caseous granulomas with central necrosis. * 95% will be fibrotic and calcified * Characterized by Ghon complex * Secondary TB - Activation of a prior Ghon complex (in sensitized host)/exogenous. Upper lobes * Fibrocaseous cavitary lesions → localized destructive. Highly infectious * Miliary TB - Secondary complicated. Spread to a new pulmonary or extrapulmonary sites (GIT, liver, adrenal gland, joints, bones) * Diagnosis – PPD (skin test), Chest X-Ray * Treatment – RIPE (Rifampin, Isoniazid, Pyrazinamide, Ethambutol). * BCG Vaccination - not 100% efficient

Answer 15

* Definition – Begins as acute bronchitis and spread locally into the lungs * Typical organisms are Strep pneumoniae, Staph aureus, H influenzae, and Klebsiella * Risk Factors – Bed ridden patients without proper treatment (↓mucus excretion) * Manifestation – Acute inflammation of bronchioles and surrounding alveoli * Inflammation tends to be bilateral, multilobar, and basilar * Usually involves the lower lobes * Lung has patchy areas of consolidation centered on bronchioles * Consequence – Usually involves focal organization -\> Fibrosis * Diagnosis – X-ray, sputum, blood * Complications [P\_SAFE] * Pleuritis – Common * Septicemia * Abscess (Lung) * Fibrous scarring and pleural adhesions * Empyema (pus in a body cavity)

Answer 16

* Definition – Tissue repair. Organization and repair of acute inflammation leads to healing by collagenous scar * Begins within 24h of injury by migration of fibroblasts and endothelial cell proliferation * Sequence * 1. Removal of debris * 2. Formation of granulation tissue * Angiogenesis – Formation of new capillaries from pre-existing capillaries * Fibroblast proliferation– beginning of scar formation by collagen synthesis * 3. Scarring * Maturation and organization of fibrous tissues * Dense Collagenous Scar and progressive contraction of the wound * Interruptions * Retention of debris * Impaired circulation * Persistent infection * Metabolic disorders, e.g. diabetes, alcohol abuse * Dietary deficiency of ascorbic acid or protein (required for collagen formation)

Answer 17

* Definition – A cavity filled with pus (neutrophils, monocytes, and liquefied cellular debris). * Usually caused by a bacterial infection * Classification – Purulent, Deep, Limited inflammation * Types * Skin abscess- usually subcutis * Internal abscess- inside the body: in an organ or in the spaces between organs * Seen in immune deficiency (Chemotherapy, Transplantation, Autoimmune disease, AIDS) * Acute abscess – Pus surrounded by a layer of acute inflammatory exudate * Chronic abscess – Exudate forming abscess wall replaced by scar tissue * Treatment – Can be removed only when mature (capsule is fully formed – roundish structure) * Examples * Ignored appendicitis -\> Liver abscess * Perianal abscess in truck drivers * Complication * Sepsis (bacteremia)- failure to contain the cause * Hospital viral infection * Cellulitis- If removed before capsule is formed / ruptured capsule

Answer 18

* Definition – Acute inflammation of the appendix – the most common surgical emergency * Cause – Associated with obstruction (Fecalith, Gallstone, Tumor, Worms) * Stages * Acute appendicitis – Obstruction -\> ↑Intraluminal pressure -\> Ischemia -\> Bacterial proliferation -\> inflammation and edema * Phlegmonous appendicitis – Spreading through full thickness of wall to Serosa -\> Acute localized Peritonitis * Gangrenous appendicitis – Muscle layer necrotic and inflamed -\> Perforation -\> bowel contents in peritoneum -\> Generalized Peritonitis * Symptoms - Pain starts in mid-epigastrium -\>Migrates to RLQ (McBurney point) * Pregnancy can mask the pain location * May elicit psoas, obturator, and Rovsing’s signs. Guarding and rebound tenderness on exam * Mimics * Meckel's Diverticulum * Salpingitis (right sided) * Mesenteric Lymphadenitis (swollen lymph nodes) * Treatment – Appendectomy * Complications – A ruptured appendix: * Necrosis of appendix wall, Perforation, Peritonitis→ gangrenous necrosis * Sepsis * Abscess

Answer 19

* Definition – Combination of liquefactive and coagulative necrosis * Macrophages wall off the infecting microorganism → granular debris * Characteristic of * Granulomatous infection (Tuberculosis/Fungal) * Atheroma * Malignant tumors * Macroscopically – Soft friable white cheese-like appearance

Answer 20

* Definition – Death of fat tissues, caused by action of lipases on adipocytes * Types - Enzymatic vs. non-enzymatic * Enzymatic - Acute pancreatitis → liquefy the membrane of fat cells in the peritoneum * Causes – Alcohol, Drugs, diet * It is a life threatening situation * Non-enzymatic - traumatic (e.g., injury to breast tissue), or ↓ Perfusion * Can present as mass, w/ giant cells and calcification * Macroscopically – Saponification- fat + calcium – Chalky Yellow-White deposits

Answer 21

* results from enzymatic destruction of fat cells * refers to focal areas of fat destruction * ex. Acute Pancreatitis * You will see fat necrosis in the pancreas * Pancreas appears edematous & is commonly hemorrhagic * Cellular injury to the pancreatic acini * Pancreas exhibits red-black hemorrhagic areas interspersed with foci of yellow-white, chalky fat necrosis * Spreads to peritoneum and peripancreatic fat

Answer 22

* Definition – Hereditary disease, ↑ serum Iron levels and hemosiderin deposition in parenchymal organs (Liver, Heart, Pancreas), can lead to organ damage * Etiology – Genetic mutation in HFE gene causing increased absorption of iron in GI * Secondary hemochromatosis is most often caused by multiple blood transfusions or in chronic viral hepatitis C. * Outcome – Bronze diabetes. A triad of: * Cirrhosis * Diabetes Mellitus * Skin pigmentation * May also lead to cardiac Arrhythmias * Diagnosis – Serum ferritin, genetic tests, liver biopsy

Answer 23

* Definition – Symptom, not a disease. Local or systemic excess of iron causes ferritin to form hemosiderin granules which are deposited inside the cell * Hemosiderin – Hemoglobin-derived, yellow-brown granular or crystalline pigment * Local excess – hemorrhage or breakdown of hemoglobin * Systemic excess - Generalized hemosiderin deposition without tissue or organ damage * Mainly from hemorrhage, multiple blood transfusions, hemolysis, and excessive dietary intake of iron * Examples * ↑ Absorption dietary iron due to an inborn error of metabolism * Blood transfusions→ iron overload * Hemolytic anemia

Answer 24

* Definition - Ruptured blood vessels in the brain, causing localized bleeding and death of brain cells * Causes * Stroke, Trauma, Aneurysm * Tumor, Amyloid angiopathy * Types * Epidural - Arterial bleeding, between the skull and the dura mater. * Almost always traumatic, usually associated with skull fracture * Clinical- Trauma→ ↑ ICP → herniation → death. Lucid interval before loss of consciousness * Subdural - Venous bleeding between dura + arachnoid mater. The most common type. * Can be due to head trauma, brain atrophy, aging, or alcoholism * Clinical- Headache, confusion, slow progression of neurological deficits * Subarachnoid - Bleeding into subarachnoid space * Usually due to ruptured “Berry’s aneurysm”, trauma, or arteriovenous malformation * Clinical- Neck rigidity, sudden excruciating headache, rapid loss of consciousness * Increased risk for developing hydrocephalus (obstructive/communicating) and ischemic infarcts * Intracerebral - bleeding into brain parenchyma, usually basal ganglia * Usually due to systemic hypertension. Also due to amyloid angiopathy, vasculitis, neoplasm * Clinical- Compression of adjacent parenchyma → Liquefactive necrosis, Hemosiderosis, death

Answer 25

* Definition – Localized increase in blood volume within a tissue * Mechanism – Active process resulting from arteriolar dilation and increased blood flow * Vasoactive mediators * Hormones * Neurogenic reflexes * Clinical manifestation – Hyperaemic tissues are redder than normal * Examples * Inflammation * Exercise * Erection

Answer 26

* Definition – Stasis of venous blood within a tissue * Passive process resulting from impaired outflow of venous blood from a tissue * Always pathological * Congested tissues are cyanotic * Types * Acute – Occurs in shock, acute inflammation, right heart failure * Also seen in: Venous obstruction, Immobility (long flights), and dehydration (alcohol/caffeine consumption, sweating, ↓humidity) * Chronic * Pulmonary congestion – due to left heart failure or mitral stenosis * Liver congestion - due to right heart failure * Complications – Chronic congestion may lead to parenchymal cell death and secondary tissue fibrosis * Treatment – Anticoagulants (e.g. aspirin)/Antiplatelets

Answer 27

* Definition – Disordered epithelial growth; begins at basal layer of squamo-columnar junction and extends outward. * Associated with HPV infection * Risk factors * #1-multiple sexual partners * Smoking * Early sexual life * Immunocompromised * Classification – Depending on extent of dysplasia * CIN 1, CIN 2, or CIN 3 (severe, irreversible dysplasia or carcinoma in situ) (CIN= cervical intraepithelial neoplasia) * Signs and symptoms – Typically asymptomatic (detected with Pap smear), or: * Abnormal vaginal bleeding (often postcoital). * Complication – May progress slowly to invasive carcinoma if left untreated

Answer 28

* Definition – Clinical syndrome. Diffuse damage of alveolar epithelium and capillaries, resulting in rapid progressive respiratory failure that is unresponsive to oxygen treatment. * Causes – Sepsis (most common), gastric aspiration, pneumonia, inhaled irritants, trauma * Loss of surfactant * Physical- Trauma (especially ↑ICP), pulmonary contusion, burns, drowning (near) * Hematologic- Blood transfusion, DIC, fat embolism * Pathogenesis * Acute Phase * Inflammation and neutrophils activation -\> capillary endothelial damage and ↑ vessel permeability -\> Exudation -\> Edema and interstitium inflammation -\> hyaline membrane formation * Organization – Fibrosis of interstitium * Signs and Symptoms – Rapid onset, within 12-18hrs. Can lead to multiple organ failure * Respiratory insufficiency, dyspnea, tachypnea * Hypoxemia and Cyanosis * X-ray - shows bilateral lung opacity ("white out") * Treatment – Treating the underlying cause and PEEP (positive end-expiratory pressure)

Answer 29

* Definition – Respiratory failure in the newborn. Lung collapse due to surfactant deficiency. * Leads to deposition of hyaline proteinaceous material in the alveoli (=Hyaline Membrane Disease) * Most common cause of respiratory distress in newborns * Causes * Immaturity of lungs – Premature babies * Pulmonary surfactant deficiency * Maternal diabetes; and C-section delivery * Signs and Symptoms * The infants are typically normal at birth, but within a few hours develop NRDS * Dyspnea, cyanosis, and tachypnea shortly after birth * Resolution – Recovery within 3-4 days in uncomplicated cases * Treatment * Corticosteroids * Surfactant injection * Oxygen – may result in retinopathy and Intraventricular hemorrhage * Prevention – Corticosteroids injection preterm to mature the lung

Answer 30

* Definition – Chronic granulomatous inflammation caused by Mycobacterium Tuberculosis * Location – Most common is lungs (Through sputum and inhalation). Also can be in GI * Symptoms - Fever, Night sweat, Weight loss, Chronic cough, Hemoptysis * Types * Primary TB - Initial infection (in non-sensitized host), Lower lobes. * Caseous granulomas with central necrosis. * 95% will be fibrotic and calcified * Characterized by Ghon complex * Secondary TB - Activation of a prior Ghon complex (in sensitized host)/exogenous. Upper lobes * Fibrocaseous cavitary lesions → localized destructive. Highly infectious * Miliary TB - Secondary complicated. Spread to a new pulmonary or extrapulmonary sites (GIT, liver, adrenal gland, joints, bones) * Diagnosis – PPD (skin test), Chest X-Ray * Treatment – RIPE (Rifampin, Isoniazid, Pyrazinamide, Ethambutol). * BCG Vaccination - not 100% efficient

Answer 31

* Definition – Acute granulomatous inflammation in response to tuberculosis in non-sensitized host * Signs and Symptoms * Usually asymptomatic * Some Flu-like symptoms * Pathogenesis * Inhalation -\> Phagocytosis -\> Inhibition of Phagolysosome formation -\> Bacterial Proliferation -\> Cell-mediated (TH1) response -\> Ghon Focus (subpleural caseous granuloma formation) * Location - Lower lobes * Resolution * Fibrosis, Calcification * Latent leftovers of bacteria can remain * Diagnosis – PPD (skin test), Chest X-Ray * Treatment – RIPE (Rifampin, Isoniazid, Pyrazinamide, Ethambutol). * BCG Vaccination - not 100% efficient

Answer 32

* Definition – Long standing granulomatous inflammation in response to tuberculosis in sensitized host * Causes – Either acquired exogenously or from primary complex (reactivation) * Locations * Lungs – Upper parts of lungs, apical segments * GI – Walls of intestine * Signs and Symptoms * Progressive disability, fever, hemoptysis, pleural effusion (often bloody), and generalized wasting * Morphology * Sharply circumscribed – Peripheral fibrosis * Central caseous necrosis * Lymphocytic infiltration * Treatment – Isolation and antibiotics (Rifampin, Isoniazid)

Answer 33

* Definition – Immune-mediated, widespread non-caseating granulomas of unknown cause * Epidemiology – More common in African-American females * Associated with Chronic interstitial lung disease - 25%, Bell’s palsy, and Erythema nodosum * Location – Involving multiple organ systems; can involve almost any organ system. * Lungs * Liver * Spleen * Skin * Clinical course – Often asymptomatic except for enlarged lymph nodes * Sometimes self-limited * Diagnosis – Chest X-Ray + biopsy * Treatment * No treatment is available * Steroids for symptomatic treatment * Complication – Pulmonary Fibrosis

Answer 34

* Definition - Heart muscle necrosis resulting from ischemia due to obstructed artery (infarction) * Severe ischemia lasting 20-40 minutes → irreversible damage -\> cardiomyocytes death -\> coagulative necrosis * Types * Transmural (regional) Myocardial Infarction (90%) * Thrombus occlusion of atherosclerotic artery * STEMI (ST-elevation MI) * Single anatomic area corresponding to a specific coronary artery * Subendocardial Infarction (10%) * Severe hypoperfusion of the main coronary arteries due to high grade atherosclerotic stenosis * Non-STEMI. ST depression, non-Q wave * Multiple foci. May be circumferential * Complications * Reinfarction/ Death * 0-24 hours [CCCP] * Cardiac Arrhythmia- the most common cause of death * Congestive Heart Failure (especially left) * Cardiogenic Shock * Pulmonary Edema * 1day-7day * Transmural MI (Pericarditis) 1-3 days * Myocardial rupture, may results in cardiac tamponade. 4-7d * Ruptured papillary muscles * Mural thrombosis → left-sided embolism * Ventricular aneurysm - Day 5 * Weeks-Months- Thromboembolic events, Dressler syndrome (secondary pericarditis)

Answer 35

* Definition – Most common malignant eye tumor in childhood * Cause – RB gene deletion/inactivation→ loss of function mutation (tumor suppressor gene) * Requires both alleles to be mutation- two hits model * Classification (all 3) * Single / Multifocal * Unilateral / Bilateral * Hereditary / Non-Hereditary * Types * Non-Hereditary (70%)- sporadic * Usually one eye (local mutation)- unilateral * Usually only one sibling * Hereditary (from both parents/one acquired mutation) (30%) * Both sided usually- bilateral * Siblings also affected * High risk for Osteosarcoma * Treatment – Removal of eyeball to prevent infiltration to optic nerve

Answer 36

* Definition – Most common malignant renal tumor in children age 2-5 * Primary renal malignancy of embryonic origin * WT1/WT2 gene loss of function mutations (Wilm’s tumor. Tumor Suppressor gene) * Presentation – Large palpable abdominal mass containing immature nephrogenic elements within non-neoplastic kidney parenchyma * Also possible: hematuria and HTN * May be part of several syndromes * WAGR Syndrome (Wilm's tumor, aniridia, genitourinary malformation, retardation) * Denys-Drash Syndrome (early onset of nephrotic syndrome) * Beckwith-Wiedemann Syndrome (macroglossia, organomegaly, hemihypertrophy)

Answer 37

* Esophagus: * Esophageal SSC * Most common maligancy of esophagus, poor prognosis * Esophageal Adenocarcinoma * has glandular differentiation and is very agressive * in white males * Stomach: * Gastric Adenocarcinoma * Invasive malignant gastric epithelial tumor with glandular differentiation. * Risk Factors - #1 H. Pylori, Diet - smoked foods, ↓Fresh fruit and vegetables * Exophytic * Diffuse infiltrative (Linitis Plastica) - Not associated with H pylori. Bad Prognosis. "Leather bottle" appearance. * Carcinoid tumor - Neuroendocrine tumors (Often secretes serotonin) (ZE Syndrome). slow growing, low-grade malignancy, liver metastasis * secretes serotonin -\> released into portal circulation * Gastrointestinal stromal tumors (GISTs) - Most common mesenchymal tumor in the abdomen. Males 60yrs; 10% \<40yrs * Gastric GISTs are less aggressive than those arising in small intestine. * Colon: * Colonic adenocarcinoma * Definition – Malignant tumors of colon with glandular differentiation * Mucinous (Colloid) Carcinoma * Carcinoma that occurs in older women (around 70yo), 10% of colon cancers. Right colon. Grows slowly over the course of many years * Papillary adenocarcinoma * Rare form of colonic adenocarcinoma (7%), Middle-aged people, may exist within a polyp or be ulcerated

Answer 38

Classification 1: * ER positive/ HER2 Negative * HER2 Positive/ ER Positive or Negative * Triple negative/ ER, PR, and HER2 Negative Classification 2: * Luminal A * Luminal B * HER2-enriched * Basal-like Classification 3: * Non-invasive * Ductal CA in situ * Lobular CA in situ * Invasive * Ductal CA * Lobular CA * Medullary CA * Colloid/ Mucinous CA * Tubular CA * Adenoid Cystic CA * Apocrine CA * Invasive Papillary CA Histological Appreances: * Solid * Comedo * Cribiform * Papillary * Micropapillary * "Clinging"

Answer 39

* Definition – Highly malignant, most aggressive lung tumor * Epidemiology * 14% of lung carcinomas * Smokers. Males \> females * Late diagnosis * Very aggressive - Poor prognosis * Location – Center/Periphery * Pathogenesis – Proliferate rapidly producing clusters * Paraneoplastic syndromes are common –Cushing syndrome (ACTH-secreting tumor) * Morphology * Central necrosis * Metastatic calcification * Small cells, scant cytoplasm * Cytoplasmic dense core of neurosecretory granules- (ADH, ACTH, PTH and more) * Treatment – Chemotherapy

Answer 40

* Definition – Malignant tumor of lung epithelium * Epidemiology * 20% of lung carcinomas * Most common in men related with smoking * Progression: metaplasia → dysplasia → carcinoma in situ → invasive carcinoma. * Location – Centrally. Main bronchi/the entire lobe * Pathogenesis * Grows fast -\> Destruction of bronchial and lung tissue * Metastasize late * Types (Histologic) * Well-Differentiated – Main feature - Keratin production and intracellular bridges * Poorly-Differentiated – No Keratin, Resembles Large cell carcinoma * Morphology [PD][Squamous Police Department] * Pink cytoplasm * Distinct borders * Treatment – Resection

Answer 41

* Definition – Invasive malignant epithelial tumor with glandular differentiation * Preceded by Atypical adenomatous hyperplasia -\> Adenocarcinoma in situ * Epidemiology * 38% of lung carcinomas * Mostly in woman, Non-smokers * Relatively good prognosis * Location – Periphery * Pathogenesis – Grows slower than Squamous Cell Carcinoma but metastasize earlier * Patterns * Acinar – Glandular formation * Lepidic – Neoplastic cells over alveolar lining with no architectural disruption or invasion. Least aggressive * Papillary/ Micropapillary * Solid (Mucin formation). Most aggressive

Answer 42

* Definition – Necrotizing inflammation of small/medium muscular arteries * Churg-Strauss syndrome is a variant of PAN * Epidemiology – Young adults and children. Males\>females * Location – Typically involving renal and visceral arteries * Sparing pulmonary circulation * Pathogenesis – Immune complex mediated * Stages * Acute lesions show fibrinoid necrosis and neutrophils * Healing lesions show prominent fibroblasts proliferation * Healed lesions show nodular fibrosis and loss of internal elastic lamina * Signs and Symptoms * Painful nodules in the affected arteries * Hypertension (due to renal arteries involvement) * Abdominal pain, bloody stool (due to GI lesions). Low grade fever * Complication – Fatal if untreated (thrombosis, aneurysm, vascular damage) * Treatment – Corticosteroids

Answer 43

* Definition – Very serious inflammation caused by colonization/invasion of heart valves or mural endocardium with infectious agents * Causes – Bacterial/fungal * Types * Acute – poor prognosis * Caused by highly virulent pathogens, such as Staph. aureus (50% of cases). * Often secondary to infection occurring elsewhere in the body. * Risk factors- IVDU and poor hygiene * Subacute * Caused by less virulent organisms, such as Strep. viridans (\> 50% of cases). * Occur in patients with congenital heart disease or preexisting valvular heart disease, often of rheumatic origin, also in DM and immunodeficiencies. * Consequences – Organization, Fibrosis, and Calcification * Complications * Cardiac- insufficiency, abscess, or pericarditis * Embolism - can occur almost anywhere in the body and can result in septic infarcts in the brain or in other organs. * Focal glomerulonephritis

Answer 44

* Definition – The most common cause of congenital cyanotic heart disease * Cause – Unequal embryonic division of aorta and pulmonary artery * Clinical features- Characterized by four abnormalities: * Pulmonary stenosis * Right Ventricular Hypertrophy – Heart enlarged and "boot-shaped" * VSD (Ventricular septal defect) * Overriding aorta * Signs and symptoms – Right to Left shunt, will lead to: * Cyanosis * Shortness of breath * Digital clubbing * Polycythemia * Treatment – Surgery in the first year of life

Answer 45

* Definition – Reflux of acidic gastric contents into lower esophagus * Causes * Incompetent lower esophageal sphincter (sphincter relaxation) * Excessive use of alcohol and tobacco * Increased gastric volume (Excessive eating) * Pregnancy * Hiatal hernia * Scleroderma * Presentation – Heartburn, regurgitation, dysphagia, and simple Hyperemia * May also present as chronic cough and hoarseness * Complications – Reflux may cause: * Esophagitis * Stricture * Ulceration * Barrett esophagus (Metaplasia)

Answer 46

* Definition – Metaplasia of esophageal epithelium * Replacement of non-keratinized stratified squamous epithelium with intestinal epithelium (non-ciliated columnar with goblet cells) in distal esophagus. * Causes – Complication of long-standing GERD * Diagnosis – Endoscopy with biopsy → “salmon pink” appearance * Complication – Constant irritations→ Dysplasia → Esophageal Adenocarcinoma

Answer 47

* Definition – Tears of esophageal mucosa * Longitudinal lacerations of gastro-esophageal junction * Confined to mucosa/ submucosa * Cause * Severe retching * Severe vomiting due to alcoholism or bulimia * Signs and symptoms * Hematemesis- Blood vomiting * Upper GI Bleeding * Treatment * Usually self-resolved after 24-48hrs * Surgery in severe cases

Answer 48

* Definition – Breach in stomach mucosa, extends through the muscularis into submucosa or deeper. Mainly at the antrum * Pain can be greater with meals, which leads to weight loss * Pathogenesis – ↓ mucosal protection against gastric acid * Background of chronic gastritis * Risk Factors * #1 – H. Pylori 70% * #2 – NSAIDs * #3 – Smoking * Bile reflux, chemotherapy, steroids * Grossly – Small (\<3 cm), sharply demarcated ('punched out'), solitary * Complications * Adenocarcinoma – Annual gastroscopy is recommended * Hemorrhage, obstruction (narrowing of lumen), and perforation * Diagnoses – By gastroscopy * Treatment – Triple therapy (H. pylori)/cause removal

Answer 49

* Definition – Breach in mucosa of duodenum extends into submucosa or deeper * More common than gastric peptic ulcer * Presented as epigastric pain that relieved with meal, which lead to weight gain * Cause – Imbalance between mucosal defense and damaging forces * Risk Factors * #1 – H. Pylori – 90% * #2 - ZE (Zollinger-Ellison) syndrome * ↑ Gastric Acid contents * Blood group O * Multiple endocrine neoplasia (MEN) type I * Morphology – Usually small, multiple * Brunner glands hypertrophy * Diagnosis – Endoscopic biopsy * Complications – Hemorrhage, obstruction (narrowing of lumen), and perforation. * Rarely malignancy

Answer 50

* Definition – The most common primary malignant tumor of liver (90%). * Bad prognosis * Risk Factors * HBV / HCV infection * Cirrhosis/ alcoholism * Aflatoxin exposure (seen in TB infection) * Other: Non-alcoholic fatty liver disease, hemochromatosis, Wilson disease, α1-AT deficiency * Pathogenesis – Can arise from: * Small-cell, high-grade dysplastic nodules in cirrhotic livers * Mature hepatocytes + progenitor cells * Morphology * Unifocal, multifocal or diffusely infiltrative soft tumor (little stroma) * Tumor masses: yellow/white/greenish (bile staining) * Areas of hemorrhage + necrosis * Vascular invasion * Complications – Cachexia, Bleeding, Liver failure, Death

Answer 51

* Definition – Variant of HCC * Occurs in young, often females (20-40yo) * Unlike HCCs, do not associated with cirrhosis, alcoholism, or HBV/HCV * Gross [Hard-FLU] * Hard * Fibrous bands * Large * Usually Single * Signs and Symptoms * Abdominal pain * Weight loss * Abdominal mass / hepatomegaly * Consequences – Tumors are often detected late due to lack of specific symptoms until it becomes sizeable. Still, better prognosis than a regular HCC

Answer 52

* Definition – A set of signs and symptoms that is the consequence of cancer in the body. * Indirect effects of Tumor/Metastases * Types * Endocrinopathy - Hormone-secreting tumors (carcinoid) from non-endocrine cells * Cushing syndrome - ACTH-secreting tumor of by small cell carcinoma of the lung * Pheochromocytoma - Catecholamine (adrenalin) secreting tumor * Neurologic abnormalities - such as dementia and peripheral neuropathies * Musculoskeletal and cutaneous - such as dermatomyositis * Hematological- Coagulation abnormalities * Migratory thrombophlebitis- associated with carcinoma of the pancreas

Answer 53

* Definition – Inflammatory bowel disease at any level of alimentary tract * Usually begins in terminal ileum / ileo-cecal valve. * Skip lesions. Rectal sparing * Remission periods, Stress induced * Morphology * Transmural inflammation → Fistula * Thick mucosa, small lumen * Cobblestone appearance * Noncaseating (non-necrotizing) granulomas * Clinical manifestations * Crampy abdominal pain and diarrhea * Malabsorption * Fever * Intestinal obstruction resulting from fibrous stricture * Fistulas between loops of intestine and between intestine, bladder, & vagina * Treatment – Corticosteroids, antibiotics, surgical resection of the affected part only

Answer 54

* Definition – Inflammatory bowel disease at the level of colon and rectum * Continuous colonic lesions, always with rectal involvement. Begins in the rectum. * Morphology * Mucosal and submucosal inflammation only * Normal serosa (no thickening, unlike Crohn's) * Pseudo-polyps * Crypt Abscess and ulcers. NO granulomas * Signs and Symptoms * Lower abdominal pain * Bloody diarrhea * Stringy mucoid material in feces * Complications * Toxic megacolon and Perforation * Adenocarcinoma (unlike Crohn's) * Treatment - Corticosteroids and Sulfasalazine

Answer 55

* Definition – Malignant tumors of colon with glandular differentiation * Epidemiology – 98% of GI tract malignancies. Peak age- 6th -7th decade * Predisposing factors * Adenomatous polyps * Inherited multiple polyposis syndromes * Long-standing ulcerative colitis * Genetic factors * A low-fiber diet that is high in animal fat * Classification * Polypoid – Proximal colon tumors - Right sided! * Locations – Cecum / Ascending colon * Gross – Polypoid fungating mass, Extends along one wall * Signs and Symptoms – fatigue and weakness due to Iron deficiency anemia * Annular – Distal colon tumors - Left-sided! * Gross – Annular lesions producing napkin-ring constrictions of the bowel * Signs and Symptoms – Occult blood in stool, changes in bowel habit * Diagnosis – Early diagnosis is crucial. Colonoscopy \> 50 years. Blood tests * Complications – Metastases (Liver)

Answer 56

* Ovarian Cysts: * 1. Nonneoplastic/ simple cysts * - follicular * - Corpus luteum * - Theca-lutein * 2. Neoplastic Cysts * - Chocolate cysts (endometrioma) * Polycystic Ovarian Syndrome * Ovarian Tumors: * 1. Surface Epithelial * - Serous * - Mucinous * - Transitional * - Endometrioid * - Brenner tumor * 2. Sex cord * thecoma * Sertoli-Leydig * Granulosa cell tumor * Ovarian malignancies: * 1. Surface epithelial * - serous cystadenocarcinoma * - Mucinous cystadenocarcinoma * 2. Germ Cell * - Dysgerminoma * - Teratoma/ Immature teratoma * - Yolk sac tumor * - Choriocarcinoma * 3. Ovarian sex cord * -stromal * - granulosa cell tumor * 4. Metastatic tumor to ovary

Answer 57

* Definition – Hyperplasia of prostatic parenchyma * Very common disorder, not considered a premalignant lesion * Characterised by stromal and glandular proliferation * Demographics – Age \> 50 * Pathogenesis – Hormonal imbalance * Estrogen → ↓Proliferation * Testosterone → ↑DHT→↑Proliferation * Location – Periurethral glands – Middle of prostate * Signs and Symptoms – ↑ frequency of urination, nocturia, difficulty starting and stopping urine stream, dysuria. * Diagnosis * PSA (Prostate-Specific Antigen)- 4 or more gray zone * DRE (digital rectal examination)- hard prostate * Complications - Chronic obstructive uropathy will lead to: * Bladder wall hypertrophy * Acute/Chronic urine retention * Failure to empty bladder → Reflux → Megaureter, Hydronephrosis→ UTI * Treatment – Medication/Transurethral resection

Answer 58

More than 90% of testicular tumors are of germ cell origin Classified as seminoma and non-seminoma malignancies * Seminoma * Non Seminoma Tumors: * Embyromal CA * Yolk Sac Tumor * Choriocarcinoma * Teratoma * Mature * Immature * w/ malignant transformation

Answer 59

* Definition – The most common malignant testicular tumour * Good prognosis * Age 40-50. Does not occur in infancy. Equivalent to female Dysgerminoma * Histologic variants * Typical/classic (85%) – Most common * Usually located within the testis * Grossly- Homogenous creamy color, lobulated * Micro- Small cells, central nuclei with two prominent nucleoli; fibrous septa, with numerous lymphocytes * Anaplastic (5-10%) * Gross- Look same as typical seminoma * Histo- Cellular and nuclear irregularity; giant cells; increased mitotic activity * Spermatocytic (4-6%) * Age \>65. Slow growing, Best prognosis * Large cells with round central nuclei and eosinophilic cytoplasm * Clinical * Painless * Progressive enlargement of one testis * Rare bilateral involvement * Treatment - Seminomas are very radiosensitive and can often be cured

Answer 60

* Definition – Complex tumor with various components from more than one germ layer * Contains multiple tissue types, such as cartilage, ciliated epithelium, liver cells, neuroglia, embryonic gut, or striated muscle. * Classification * Mature – Various well-differentiated tissues * Usually in childhood * Almost always malignant (unlike in women, which is rarely malignant) * Laying in fibrous /myxoid stroma * Immature * Malignant * Elements of all germ layers incompletely differentiated (primitive neural elements) * Not arranged * Malignant transformation * Typically in adults * Contains malignant tissue, such as squamous cell carcinoma/ Adenocarcinoma * Clinical – ↑AFP and hCG 50% of cases

Answer 61

* Definition – Common malignant tumor of melanocytes with significant risk of metastasis. * Epidemiology – Incidence is increasing at a rapid rate, with peak age 40-70 * Prognosis is based on Breslow-Clark scale (depth and thickness) * Risk factors * Chronic sun exposure / Sunburn * Fair-skinned persons * Dysplastic nevus syndrome * Familial melanoma * Location – Males- upper back, Females- back and legs * Presentation – [ABCD] asymmetry, irregular borders, ununiformed color, diameter \>6mm * First phase- radial growth, later- vertical growth (into deep dermis) * Types * Superficial spreading melanoma- The most common type. Horizontal growth pattern * Lentigo malignant melanoma- Face / neck of older individuals. Has the best prognosis * Acral lentiginous melanoma- Most common melanoma in dark-skinned individuals; affects palms, soles, and subungual area (beneath the nails) * Nodular melanoma is a nodular tumor, vertical growth. The worst prognosis * Treatment – Surgical excision with wide margins. Chemotherapy in Systemic disease

Answer 62

* Definition – The most common of all malignant skin tumors * Most common in middle-aged or elderly individuals * Epidemiology – Arises from basal cells of hair follicles * Grows slowly * Almost never metastasizes * Risk factors – Chronic sun exposure, immunosuppression, xeroderma pigmentosum * Location – Sun-exposed areas of body. Most commonly eyes and nose * Locally invasive, but rarely metastasizes. * Types * Nodular * Morphoeic * Superficial * Presentation – Firm, raised, waxy, pearly (pink) nodules * Appear as non-healing ulcers * Commonly with telangiectasia, rolled borders, central crusting or ulceration. * Treatment – Usually curable by surgical resection

Answer 63

* Definition – The most common benign breast tumor in women \< 35 years old. * This tumor is entirely benign and is not a precursor of breast cancer. * Stromal tumor- composed of fibrous tissue and glands * The lesion is firm, rubbery, painless, and well-circumscribed. * Clinical features * Increased size and tenderness of mass with pregnancy or menstrual cycle * No overlying skin changes * No lymphadenopathy * No nipple retraction * Subtypes * Intracanalicular - stroma compresses and distorts glands * Pericanalicular - glands retain round shape * Treatment – No treatment or simple excision * Phyllodes tumor - Fibroadenoma variant. * Large mass of connective tissue and cysts with irregular margins causing asymmetric breast * Most common in 5th decade. Some may become malignant

Answer 64

* Definition – Invasive carcinoma that arises from cervical epithelium * Middle-aged women 45yrs, 10-15yrs after detection of precursor CIN * Subtypes * Squamous cell carcinoma (80%) * Adenocarcinoma * Risk factors – Oncogenic HPV infection, Early sexual life, Multiple sex partners * Clinical * Difficult to diagnose without a pap smear - catch dysplasia (CIN) before it develops into carcinoma, detects early HPV infection * Grading - 1-3 (well-differentiated, moderate, poorly differentiated) based on cellular differentiation * Staging - 1-4 depending on clinical spread * Signs and symptoms – Vaginal bleeding, leukorrhea, painful coitus, dysuria * Diagnosis – Screening with Pap smear, biopsy * Treatment – Hysterectomy + lymph node dissection * Complication – Lateral invasion can block ureters → hydronephrosis → renal failure

Answer 65

* Bacterial Meningitis (Acute purulent meningitis) * Definition – Purulent leptomeningeal (pia + arachnoid) inflammation due to bacteria * Etiology – The infecting organisms vary with age: * Neonates are infected most frequently with group B streptococci and Escherichia coli. * Infants and children - Haemophilus influenzae * Adolescents and young adults - Neisseria meningitides * Elderly - most frequently Strep. pneumoniae and Listeria monocytogenes. * Clinical features * CSF examination - neutrophilic infiltration, ↑ protein, and ↓ glucose * Fever, headache, photophobia * Hydrocephalus (herniation secondary to cerebral edema) * Hearing loss and seizures (due fibrosis) * Viral Meningitis (Aseptic Meningitis) * Etiology – Enterovirus (Coxsakie), Herpes simplex viruses, HIV, Polio * Clinical – Meningeal irritation: Headache; Nuchal rigidity; fever * Usually self-limiting, low mortality * CSF examination - lymphocytic infiltration, mild ↑ protein, and normal glucose

Answer 66

* Definition – The most common primary brain tumors They can be divided based on their infiltration into the surrounding brain parenchyma. * Types * Astrocytomas that do not infiltrate the brain: * Pilocytic astrocytomas – benign. Children and young adults. 3rd ventricle, thalamus. * Pleomorphic Xanthroastrocytomas – low grade (II). Temporal lobe → seizures * Subependymal giant cell astrocytomas – benign, grade I. often asymptomatic. Seen in tuberous sclerosis. * Diffuse Astrocytomas can be further subdivided based on grade: * Low-grade fibrillary astrocytomas are grade II. Well differentiated. Arise from white matter of cerebral hemisphere. 5-years survival rate- 65%. Treatment- surgery * Anaplastic astrocytomas are grade III. Great nuclear pleomorphism + mitotic activity * Also occur in cerebral hemispheres. Arise in the fifth to sixth decade * Glioblastoma multiforme (GBM) is grade IV. \<1-year survival rate * The most common primary CNS malignancy * Most arise in the fifth or sixth decade, male predilection * Areas of hemorrhage and necrosis are surrounded by a “pseudopalisade” arrangement of tumor cells. Microvascular proliferation.

Answer 67

* Definition – Glioblastoma is the most common primary CNS malignancy * Grade IV tumor - Progresses rapidly and has a poor prognosis \< 1 year * Most arise in the fifth or sixth decade, male predilection * Location – white matter of cerebral hemisphere * Presentation – depends on location of tumor * Some symptoms include headache, seizures, or focal deficits * Histologically – Areas of hemorrhage and necrosis are surrounded by a “pseudopalisade” arrangement of tumor cells. * Microvascular proliferation. * Treatment * Surgical removal/resection * Radiation and chemotherapy

Answer 68

* Definition – Malignant neoplastic proliferation of large cells called Reed-Sternberg cell with features resembling an inflammatory disorder (e.g., fever, inflammatory cell infiltrates). * The most common type of lymphoma * Localized to a single group of nodes + contiguous spread * Tumor consists mostly of reactive lymphocytes, macrophages, eosinophils, plasma cells and stromal cells mixed with Reed-Sternberg cells * Diagnosis – Depends on these histologic findings * Ann Arbor staging – Characteristic for lymphomas. Classification based on: 1.Degree of dissemination. 2.Involvement of extralymphatic sites. 3.Presence/absence of systemic signs * Rye classification * Nodular sclerosis - The most common (70% HL cases) * More common in females. Rarely associated with EBV infection. Relatively good prognosis. * Often arises in the upper mediastinum, lower cervical, or supraclavicular nodes. * Lymphocyte-rich (predominant) - Rare, composed mainly of reactive lymphocytes. * Men \> women. EBV association - 40% of cases. The clinical course is moderately aggressive. * Mixed cellularity - Older persons. Men \> women. EBV association - 70% of cases. * The clinical course is moderately aggressive * Lymphocyte depletion - The least common, the poorest prognosis * EBV association in the great majority of cases

Answer 69

* Diffuse Astrocytomas * Low grade fibrillary astrocytomas * Anaplastic Astrocytomas * Glioblastoma multiforme * Oligodendrogliomas * Ependymoma * Medulloblastoma * Metastasis from other parts of body * lung, breast, melanoma, colon , kidney