A. Hematology is the medical study of blood, its related structures, associated diseases and conditions, and treatments.
B. Oncology is the medical study of cancers and their treatment.

II. Hematology.
A. Structure and function of blood. (Overhead T21-2)
1. Blood is made up of four components: red blood cells, white blood cells, platelets, and plasma.
2. Blood cells and other blood elements are produced and developed through a process called hemopoiesis.
(a) Blood cells originate in bone marrow.
(b) They develop from immature cells called stem cells.
3. Red blood cells (rbc’s or erythrocytes) contain hemoglobin, which is responsible for carrying oxygen to tissues throughout the body.
(a) The spleen is responsible for removing and destroying old and damaged rbc's.
(b) These rbc’s are converted into bilirubin in the liver, recycled back into the vascular system, or removed from the body through the gastrointestinal tract.
4. White blood cells (wbc’s or leukocytes) play an important role in the immune system.
(a) The different types of leukocytes are lymphocytes, eosinophils, basophils, neutrophils, and monocytes.
(b) Leukocytes were discussed in Chapter 20.
5. Platelets (thrombocytes) have a major function in aiding blood clotting.
(a) Platelets form the initial response to blood vessel injuries.
(b) Platelets adhere to the lining of blood vessels and then aggregate to form a primary plug to help stop bleeding.
6. Plasma constitutes 55% of blood and composes the fluid portion of blood.
(a) Plasma contains four major proteins: albumin, globulin, fibrinogen, and prothrombin.
(b) Fibrinogen and prothrombin are important in the blood clotting process.

B. Blood grouping. (Overhead T21-3)
1. Human blood types are categorized by using the ABO blood classification system.
2. There four main groupings: A, B, AB, and O.
3. Within each blood grouping red blood cells have one or two specific antigens. Individuals with type O blood do not have any antigens.
4. Because blood types are genetically determined, a person's blood type remains the same throughout his or her life.
5. Blood groups become very important for a patient who is to receive a blood transfusion.
6. In certain situations, if a person is given blood of the wrong type, he or she will have an adverse reaction referred to as agglutination.
7. Another antigen that may cause compatibility problems is Rh factor.
(a) The term Rh positive indicates a person who was born with Rh factor on his or her rbc's.
(b) Problems can occur in pregnancies in which an Rh-negative women becomes pregnant with an Rh-positive baby.

C. Blood clotting. (Overhead T21-4)
1. Coagulation is the body’s natural response to a vascular injury.
2. The process is referred to as the coagulation cascade because it is a continuation of steps.
(a) When a blood vessel is injured, the platelets respond by aggregating around the injury.
(b) A network of protein fibers called fibrin forms a clot (or coagulum) that traps blood cells and fluid.

3. There are currently a total of 12 known clotting factors (numbered I through V and VII through XIII) that must work together to coagulate blood.

4. A deficiency in any of these clotting factors can result in a bleeding disorder.

D. Examining blood. (Overhead T21-5)
1. The examiner asks about any symptoms such as fatigue, ease of bruising, and the slow healing of wounds.
2. The examiner looks for any signs of lethargy, unusual pallor, or skin discoloration.
3. A physical examination is performed to rule out problems with other organs that may be causing the symptoms.
4. Routine blood tests are frequently ordered as part of the examination.

E. Hematologic diseases and conditions. (Overhead T21-6)
1. Acute lymphocytic leukemia (ALL): a group of neoplasms characterized by abnormal B or T lymphocytes. Predominately seen in children 3-5 years old.
2. Acute myelogenous leukemia (AML): a disease characterized by the inability of the wbc's to mature. Primarily affects adults between the ages of 15 and 39 years.
3. Anemia: any condition in which the blood's ability to transport oxygen is impaired.
4. Chronic lymphocytic leukemia (CLL): a type of leukemia characterized by proliferation of mature-appearing lymphocytes in the circulating blood and proliferation of lymphoid tissue in various sites.
5. Chronic myelogenous leukemia (CML): a type of leukemia characterized by extreme overproduction of granulocytes.
6. Embolus: any plug that blocks a blood vessel.
7. Hemophilia: a hereditary deficiency in clotting factor VIII or IX resulting in a tendency to hemorrhage.
8. Leukemia: a group of disorders characterized by the progressive proliferation of abnormal leukocytes.
9. Sickle cell anemia: an inherited chronic hemolytic anemia that is characterized by sickle-shaped rbc's.
10. Thrombosis: formation of a blood clot, which can lead to occlusion of a blood vessel.

F. Common diagnostic tests and procedures in hematology. (Overhead T21-7)
1. Blood culture: blood is placed in a growth medium and allowed to incubate in order to test for abnormal microorganisms or abnormally large numbers of microorganisms.
2. Bone marrow aspiration: a sample of bone marrow is removed and examined to determine the amount of hemopoietic activity that is occurring.
3. Flow cytometry: specific types of blood cells are counted, in particular the different types of lymphocytes. Used in classifying leukemias.
4. Free erythrocyte protoporphyrin (FEP): used in diagnosing iron-deficiency anemia.
5. Peripheral blood smear examination; stained red cell examination: microscopic examination of a blood smear for the size, shape, structure, and staining properties of the individual blood cells.
6. Radioimmunoassay (RIA): radioactive chemicals and antibodies are used to measure hormone and drug levels in plasma.
7. Red cell size distribution width (RDW): the size of rbc's is measured. Sizes outside the normal range can be indicative of a number of disorders.

G. Blood coagulation tests. (Overhead T21-8)
1. Antithrombin III (AT-III): checks for an abnormally low level of antithrombin. Aids in diagnosis of states involving hypercoagulation such as venous thrombosis.
2. Clot retraction: measures time required for blood to form a firm clot.
3. Thrombin time (TT), thrombin clotting time (TCT): measures the time required for blood to form a clot when thrombin is added.
H. Abnormal conditions of red blood cells. (Overhead T21-9)
1. Abnormal conditions include acanthocytosis, macrocytosis, and microcytosis.
2. Abnormal types and formation of rbc's include burr cell, sickle cell, and target cell.
3. Abnormal inclusions in rbc's include Cabot bodies, Heinz inclusion bodies, and Howell-Jolly bodies.

I. Leukemia. (Overhead T21-10)
1. Leukemia is cancer of the white blood cells and is characterized by an abnormal proliferation of wbc's.
2. The four most common types are acute lymphocytic, acute myelogenous, chronic lymphocytic, and chronic myelogenous
3. Acute lymphocytic and acute myelogenous leukemias are staged using the French-American-British (FAB) Classification System of Acute Leukemias.

1. Antianemic: replenishes below-normal iron levels in blood.
2. Anticoagulant: prevents formation of blood clots (thrombi) but is ineffective on existing clots. Used to prevent deep venous thrombosis (DVT), clots, and strokes.
3. Hemostatic: stops flow of blood in blood vessels. Specific clotting factors (usually factor VIII) are given intravenously.
4. Thrombolytic: dissolves thrombi by enzymatic action to relieve obstructions in arteries.
5. Vitamin B12: increases the production of erythrocytes. Used to treat pernicious anemia.

K. Therapeutic procedures in hematology. (Overhead T21-12)
1. Bone marrow transplant: transplantation of stem cells from a person who is HLA compatible. Used to treat leukemias and aplastic anemia.
2. Plasma, fresh frozen: Intravenous administration of an unconcentrated form of all clotting factors except platelets.
3. Platelet concentrates: intravenous administration of concentrated platelets. Improves clotting ability of blood.
4. Whole blood transfusion: intravenous replacement of whole blood.

III. Oncology. (Overhead T21-13)

A. Introduction.
1. Cancer is a malignant tumor (also called a neoplasm).
2. It is characterized by uncontrolled growth and excessive multiplication of cells.
3. It is generally considered to be life threatening.
4. Carcinogenesis is the process by which a healthy cell becomes a malignant cell.
(a) The cause is unknown but may be related to environmental and genetic factors.
(b) Transformation occurs in the DNA (deoxyribonucleic acid) of the cell.
(c) Some viruses are carcinogenic (human T cell leukemia virus, Epstein Barr virus, hepatitis B virus, and Kaposi sarcoma herpesvirus).

B. Pathology of cancer.
1. Anaplastic cells are undifferentiated cells found in malignant tumors that can reproduce quickly.
2. Dysplastic cells are characterized by cell changes including loss of uniformity and structural organization.
3. Growth rate of a tumor correlates with its level of differentiation. The less differentiation the cells have, the quicker the tumor can grow.
4. When cancer has spread from it site of origin to distant organs, it has metastasized.

C. Types of cancerous tumors.
1. Hematologic tumors include multiple myeloma and various forms of leukemia and lymphoma.
2. Carcinomas orig0inate from epithelial cells.
(a) Adenocarcinomas are derived from glandular cells.
(b) Squamous cell carcinoma are derived from squamous cells.
3. Sarcomas originate from connective tissue, such as muscle and bone.

D. Cancers by body system. (Overhead T21-14)
1. Skin: basal cell carcinoma, Kaposi sarcoma, malignant melanoma, squamous cell carcinoma
2. Eyes: retinoblastoma, uveal melanoma
3. Ear, nose, and throat: cancer of the oral cavity, cancer of the paranasal sinuses, cancer of the pharynx, cancer of the salivary glands
4. Endocrine: adenoma, papillary carcinoma, thyroid cancer
5. Respiratory: bronchogenic carcinoma
6. Heart and blood vessels: cardiac sarcoma
7. Gastrointestinal: anorectal cancer, colorectal cancer, adenosarcoma, pancreatic cancer, cancer of the small intestine
8. Female reproductive: breast cancer, cervical cancer, endometrial cancer, ovarian cancer, vaginal cancer
9. Genitourinary: bladder cancer, prostate cancer, testicular cancer
10. Musculoskeletal: Ewing tumor, multiple myeloma, osteosarcoma
11. Neurologic: brain tumor, spinal cord neoplasm
12. Endocrine: thyroid cancer
13. Immune: Hodgkin lymphoma, non-Hodgkin lymphoma
14. Blood: various types of leukemias


E. Common diagnostic tests and procedures in oncology. (Overhead T21-5)
1. Core needle biopsy: removal of tissue using a large-bore needle.
2. Endoscopic biopsy: removal of tissue from normally inaccessible sites using an endoscope.
3. Exfoliative biopsy: direct smear or scrape and examination of shed cells.
4. Laparoscopy: use of a laparoscope to visualize the abdominal cavity for abnormalities and growths. Insertion is through a small incision near the umbilicus.
5. MRI: use of magnetic energy and radiofrequencies to stimulate body cells to emit radio signals that are converted to images. MRI is useful in locating and examining tumors in a specific part of the body.
6. Sentinel node biopsy: injection of an isotope near a lesion followed by a scan to detect the spread of the isotope. The node that picks up most of the isotope is then excised and examined.

F. Grading and staging tumors. (Overhead T21-16)
1. The level of differentiation of a tumor is described as its grade.
(a) Cancers are classified as grades I through IV.
(b) A higher grade implies a more aggressive cancer and a worse prognosis.
2. The extent of the spread of cancer is described as its stage.
(a) It is based on the size of the primary lesion, extent of spread to regional lymph nodes, and the presence or absence of metastases.
(b) The most commonly used staging system is the TNM system.
(c) T for tumor.
(d) N for regional lymph node involvement.
(e) M for metastasis.
(f) Example: T2N2M0

G. Drug classifications in oncology. (Overhead T21-17)
1. Alkylating agent: chemotherapy drug used to inhibit cell division by causing DNA breakage.
2. Antimetabolite: treatment of neoplasms by disrupting cell metabolism, thereby causing cell death.
3. Antimitotic: chemotherapy agent that prevents cell division.
4. Corticosteroid: chemotherapy agent that reduces inflammation of healthy tissue.
5. Hormonal agent: chemotherapy drug that specifically targets hormonally responsive tumors.

H. Therapeutic procedures in oncology can be divided into four categories. (Overhead T21-18)
1. Surgery is the most common form of treatment for solid malignancies.
2. Chemotherapy uses drugs to affect tumor cells.
(a) Different drugs affect tumor cells at different phases of their cell growth.
(b) Chemotherapy is often given as a combination of drugs, called protocols.
3. Radiation therapy (radiotherapy) is used alone or in conjunction with other treatments. It can be directed to a specific area.
4. Biological therapy (immunotherapy) stimulates the body’s own immune system to respond to fight the growth of tumors.