RadPatho

Pathology

The study of diseases that can cause abnormalities in the structure or function of various organ system.

Disease

Pattern of the body's response to some form of injury that causes variation of normal conditions.

Pathogenesis

The sequence of events that lead to cellular changes and observable manifestations.

Symptoms

Subjective, perceived by the patient.

Ex: headache

Signs

Objective, detected by a physician.

Ex: fever, swelling

Asymptomatic.

Disease processes, especially in the early stages, do not produce symptoms and are termed

Syndrome

A group of signs and symptoms that define a specific condition.

Etiology

• study of the cause of disease.

• Common agents that cause diseases include:

  • Viruses

  • Bacteria

  • Trauma

  • Heat

  • Chemical agents

  • Poor nutrition

1. Viruses

2. Bacteria

3. Trauma

4. Heat

5. Chemical agents

6. Poor nutrition

Etiology is the study of the cause of a disease such as:

Iatrogenic

• Diseases caused by physicians or their treatment.

• Reactions are adverse responses to medical treatment itself (e.g., a col lapsed lung that occurs in response to a complication that arises during arterial line placement).

Nosocomial

Infections at the acute care facility.

Community Acquired

Infections that develop outside the healthcare facility.

Idiopathic

Underlying cause is uknown.

Acute

Quick onset and last for a short period.

Sequelae

May be followed by lasting effects.

Ex:

• Stroke

• Cerebrovascular Accident

Chronic

Disease may manifest more slowly and last for a very long time.

Ex:

• Multiple Sclerosis

• Diabetes Mellitus

Diagnosis

The identification of a disease an individual is believed to have.

Prognosis

Predicted course and outcome of the disease.

Morphology

The structure of cells of tissue.

Subtractive/Lytic/Destructive Diseases

Pathologic condition where there is a decrease in tissue density, require a decrease in radiographic exposure.

Additive/ Sclerotic Diseases

Pathologic condition where there is an increase in tissue density, require an increase in radiographic exposure.

Epidemiology

The investigation of disease in large groups.

Health care epidemiology

Grounded in the belief that the distributions of health states (good health, disease, disability, and death) are not random within a population and are influenced by multiple factors, including biologic, social, and environmental factors.

Prevalence

Number/total cases in a given population

Incidence

Number of new cases found in a given period.

Endemic

• Disease commonly found in a specific area.

• Diseases of high prevalence in an area where a given causative organism is commonly found;

Epidemic

Sudden increase in cases in an area.

Mortality rate

The average number of deaths caused by a particular disease in a population.

Inflammation

Initial response of body tissues to local injury.

1. Dilation

2. Heat and Redness

3. Swelling

4. Fever

Inflammation process includes:

Dilation

Of arterioles, capillaries, and venues (hyperemia).

Heat and Redness

Venues and capillaries become abnormally permeable (allowing exudate in the surrounding tissue.)

Swelling

Produces pressure on sensitive nerve endings (Pain).

Fever

Common inflammatory conditions.

1. Rubor (redness)

2. Calor (Heat)

3. Tumor ( swelling)

4. Dolor (pain)

5. Loss of function

Clinical signs of Inflammation

1. Alteration in blood flow and vascular permeability

2. Mitigation of circulating WBC to the interstitium of the injured tissue

3. Phagocytosis and enzymatic digestion of dead cells and tissue elements

4. Repair of injury by generation of normal parenchymal cells of proliferation of granulation and eventual scar formation.

Events that occur in Inflammatory response:

Edema

Accumulation of abnormal amounts of fluid in the intercellular tissue spaces of body cavities.

Localized

Inflammatory reaction

Anasarca

Generalized edema occurs with pronounced swelling of subcutaneous tissues throughout the body.

Ex:

• Congestive Heart Failure

• Liver Cirrhosis

• Renal Disease

Elephantiasis

Local obstruction of lymphatic drainage (filariasis)

Ischemia

Refers to the interference with the blood supply to an organ or part of an organ. Commonly seen in Anemic or cyanotic patients.

1. Narrowing of arterial structures (atherosclerosis)

2. Thrombotic or embolic occlusion.

Ischemia is caused by:

These undergo irreversible damage if deprived of their blood supply for 3 to 5 mins.

Infarct

Localized area of ischemic necrosis within a tissue or organ produced by occlusion of either its arterial supply or its venous

Necrosis

Tissue death that may be caused by lack of blood supply.

Gangrene

Conditions that results from death of tissue due to lack of blood supply,

Hemorrhage

Rupture of blood vessels; Trauma, atherosclerosis, an inflammatory or neoplastic erosion of vessels.

Hematoma

Trapped blood within the body tissues.

Petechiae

Minimal hemorrhage into the skin, mucous membranes, or serosal surfaces.

Purpura

Slightly larger hemorrhage.

Ecchymosis

Large (greater than 1 to 2 cm) subcutaneous hematoma.

1. Atrophy

2. Hypertrophy

3. Aplasia

4. HyperpIasia

5. Hypoplasia

6. Metaplasia

7. Dysplasia

Alterations of cell growth includes:

Atrophy

Reduction in the size or number of cells in an organ tissue.

Hypertrophy

Increase in the size of cells in an organ or tissue

Aplasia

Failure to develop

Hyperplasia

Increased number of cells.

Hypoplasia

Underdevelopment

Metaplasia

Conversion of one cell type into another cell type that is not normal for that tissue.

Dysplasia

Loss of uniformity of individual cells and their architectural orientation.

Neoplasia

• Latin words meaning "New Growth" (Tumor)

• Abnormal proliferation of cells

• Can be benign or malignant.

• Cells acts as parasites, competing with normal cells and tissues for their metabolic needs.

Cachexia

Tumor cells flourish; patient becomes weak and emaciated.

Oncology

• Study of neoplasms

• Greek words "oncos", meaning tumor.

• Parenchyma

• Supporting Stroma

Basic Components of Tumors:

Parenchyma

• (organ or tissue) - made up of proliferating neoplastic cells.

• Determines how the tumor behaves.

Supporting Stroma

• (tissue) - made up of connective tissue, blood vessels, and possibly lymphatic vessels.

• Determines how the tumor is named.

Benign tumors

• Resembles the cells of origin in structure and function

• Remain localized and can be surgically removed.

• Affected organs:

1. Pituitary

2. Islets of Langerhans

3. Brain

4. Spinal cord

5. Trachea

6. Esophagus

• Ends in -oma

• Ex: Fibroma, Chondroma, Adenoma, Cystadenoma, Lipoma, Myoma, Angioma, Papilloma (polyp)

1. Pituitary

2. Islets of Langerhans

3. Brain

4. Spinal cord

5. Trachea

6. Esophagus

What are the Affected Organs with Benign tumors?

Malignant tumors (Cancer)

• Invades and destroys adjacent structures and spread to distant sites (metastasize).

• Poorly differentiated (may be impossible to determine which organ they originate)

• Are called carcinomas

• Affects epithelial tissues, skin, and mucous membranes lining body cavities.

• Ex: Adenocarcinoma, Basal cell carcinoma, Squamous cell carcinoma.

Cancer

Latin word "Karnikos" meaning "crab” (has fingerlike projections)

Staging of malignant tumor

• Extensiveness of a tumor at its primary site

• Presence or absence of metastases to lymph node and distant organs

• Determines the most appropriate therapy

Surgically Removal

What is the appropriate therapy for a Localized tumor?

Radiation Therapy

What is the appropriate therapy for Hodgkin's disease?

Hormonal Therapy

What is the appropriate therapy for Prostate cancer?

Sarcoma

• Highly malignant tumors arising from connective tissue such as bone, muscle, and cartilage.

• Less common than carcinoma, but tend to spread more rapidly.

• Ex: Fibrosarcoma

Carcinogens

• Substance that promotes carcinogenesis;

• Formation of cancer

1. Air and water pollution

2. Cigarette smoke

3. Asbestoss

4. Food

5. Cosmetics

6. Plastic

7. Excessive exposure to sunlight.

Chemical Carcinogens include:

Metastasis

The spread of malignant cancer cells resulting in a secondary tumor distant from the primary lesion.

1. Seeding within the body.

2. Lymphatic spread

3. Hematogenous spread

Malignant neoplasms disseminate to distant sites by one of three ways:

Seeding (diffuse spread)

• Cancerous cells travel to a distant site or a distant organ system.

• Neoplasms invade body cavities.

• GIT to the peritoneum to distant sites.

Lymphatic spread

• Major metastatic route of carcinomas (Lung and breast).

• Depends on the site and the natural lymphatic drainage (sentinel node)

• The lymph node into which the primary neoplasm drains is termed sentinel node

Hematogenous spread

• Or Metastatic spread

• Invasion of the circulatory system

• Complex process involving several steps

• Invade and penetrate blood vessels, travel as neoplastic emboli, can be trapped in small vessels.

• Certain types of cancer appear more often as metastases from other areas rather than - originating in a given organ.

Invasion

If the cancerous cells spread into surrounding tissue by virtue of the proximity of the areas.

T (Tumor in Tumor - Node - Metastasis System)

• Refers to the size and extent of the main tumor. The main tumor is usually called the primary tumor.

• It can be classified as: 1,2,3, or 4, with 1 being small and 4 large.

Fungi

• Microorganisms forming complex structures

• Grows mold or yeast

• Example: Pneumonia

N (Node in Tumor- Node-Metastasis System)

• Refers to the nearby lymph nodes that have cancer.

• It can be classified between 0 and 3

• 0 — no lymph nodes containing cancer cells.

• 3 — lots of lymph nodes containing cancer cells.

M (Metastasis in Tumor - Node - Metastasis TNM system)

• Refers to whether the cancer has metastasized. This means that the cancer has spread from the primary tumor to other parts of the body.

• It can be classified as either 0 or 1

• 0 — the cancer hasn't spread

• 1 — the cancer has spread.

In situ

Abnormal cells are present but have not spread to nearby tissue.

Localized

Cancer is limited to the place where it started, with no sign that it has spread.

Regional

Cancer has spread to nearby lymph nodes, tissues, or organs.

Distant

Cancer has spread to distant parts of the body.

Unknown

There is not enough information to figure out the stage.

Grading of Malignant Tumor

• Assesses aggressiveness or degree of malignancy.

• Indicates its biological behavior.

• Allow prediction of its responsiveness to therapeutic agents.

• How abnormal the tumor cells and the tumor tissue look under a microscope.

• Grade 1

• Grade 2

• Grade 3

• Grade 4

• GX

Malignant Tumors are graded into:

Grade 1

• The cancer cells look very similar to normal cells and are growing slowly

• Well differentiated and low grade

Grade 2

• The cells look unlike normal cells and are growing more quickly than normal.

• Moderately differentiated and Intermediate grade

Grade 3

• The cancer cells look very abnormal and are growing quickly.

• Poorly differentiated and High grade.

Grade 4

• Tumors tend to grow rapidly and spread faster.

• Undifferentiated and High grade.

GX

Means that the grade can't be assessed. It is also called undetermined grade.

Diseases

• are grouped into several broad categories. Those in the same category may not necessarily be closely related, but groupings tend to produce lesions that are similar in morphology— that is, their form and structure.

Congenital Disease

• Diseases present at birth and resulting from genetic or

  environmental factors caused by abnormalities in the number

  and distribution of chromosomes.

• Example: Down Syndrome