Altered Cell Growth and Cancer Development

Iggy—Chapter 27

Characteristics of Normal Cells

Have limited cell division Specific morphology Small nuclear cytoplasmic ratio Perform specific differentiated functions Adhere tightly together Are non-migratory Grow in an orderly and well-regulated

manner Are contact inhibited

Mitosis of Normal Cells

Cell Cycle G1 S G2 M G0

http://www.cellsalive.com/cell_cycle.htm

Abnormal Cells

Hypertrophy—increase in tissue size by enlarging each cell.

Hyperplasia—increase in tissue size by increasing the number of cells

Neoplasia—new cell growth not needed for normal body growth or replacement of dead or missing tissue.

Characteristics of Benign Cells

Continuous or inappropriate cell growth Specific morphology Small nuclear cytoplasmic ratio Perform differentiated functions Adhere tightly together Are non-migratory Grow in an orderly manner

Characteristics of Malignant Cells Rapid or continuous cell division Anaplastic morphology Large nuclear cytoplasmic ratio Lose some or all differentiated functions Adhere loosely together Are able to migrate Grow by invasion Are not contact inhibited

Cancer Development

Carcinogenesis/oncogenesis Malignant transformation-changes a

normal cell to a cancer cell 4 stages

– Initiation– Promotion– Progression– Metastasis

Metastasis

The breaking off and establishing remote tumors– Metastatic– Secondary

Metastasis

Extension into surrounding tissues Penetration in blood vessels Release of tumor cells Invasion of tissue at site of arrest Local seeding Blood-borne metastasis Lymphatic spread

Steps of metastasis

Cancer Classification

From type of cell they arise from Biologic behaviors Anatomical sites Degree of differentiation 2 major types

– Solid– Hematologic

Cancer Grade and Stage

Grading– High grade– Low grade

Staging– Clinical– Surgical– Pathologic

TNM (T) Tumor

– Tx – unable to assess– T4 – larger number signifies increasing size

(N) Node– Nx – unable to assess– N3 – increased node involvement

(M) Distant Metastasis – Mx – unable to assess– M1 – no distant mets– M2 – distant mets

Cancer Etiology and Genetic Risk

Oncogene activation

External factors– Chemical– Physical

RadiationChronic irritation

– Viral

Advancing age is the single most important risk factor for cancer

77% of cancer is in people age 55 or older

The older a person is, the less ability their immune system retains to repair mutations that occur

Genetic testing for cancer

Requires a blood sample Very expensive Frequently not covered by

insurance Does not diagnose the presence

of cancer

Prevention

Primary Secondary Chemoprevention Gene therapy

Seven Warning Signs of Cancer

C – Changes in bowel or bladder A – A sore that does not heal U – Unusual bleeding or discharge T – Thickening or lump in breast or elsewhere I – Indigestion or dysphagia O – Obvious change in wart or mole N – Nagging cough or hoarseness

General Intervention for Clients with Cancer

Iggy—Chapter 28

Common Problems

Impaired immune and hematopoietic function

Altered gastrointestinal tract structure and function

Motor and sensory deficits Decreased respiratory function Treatment-related consequences

Ways to Treat Cancer

Surgery Radiation Chemotherapy

Surgery

Prophylaxis Diagnosis Cure Control (debulking) Palliation Therapy effectiveness Reconstructive or rehabilitative

Radiation

Kills cancer cells with minimal exposure of normal cells to radiation

Cells damaged by radiation either die or become unable to divide

Works best in localized tumors

Penetrating capacity ofdifferent types of radiation

Radiation Administration

Amount of radiation delivered to a tissue is called “exposure”

Amount of radiation absorbed by the tissue is called the “dose”

Total dose depends on the tumor location and its sensitivity to radiation

Doses are given in fractionation divided over the treatment time span

Types of Radiation Therapy

Teletherapy – beam radiation Brachytherapy – short or dose therapy

– All types—radiation source is placed in the patient—making the patient emit radiation and be a hazard to others for a short time

Unsealed isotope—example is radioactive iodine concentrate (thyroid gland)

Sealed—Seeds (prostate Ca) short half life, usually left in place

Implants—constant in hospital several or intermittent in and out of clinic over a period of time

The Inverse Square Lawof Radiation Exposure

The intensity of radiation decreases with distance from the radiation source.

Side Effects of Radiation

Limited to areas of exposure Skin changes and hair loss usually

permanent Care of patient receiving radiation includes:

– Teaching– Don’t remove radiation markings– Skin care to radiated areas– No lotions or creams, use radigel provided by

radiologist

Chemotherapy

Used for both cure and to increase survival time

Works best for systemic (mets) May be used in combination with

surgery and/or radiation (adjuvant)

Chemotherapy

Antimetabolites—counterfeit metabolites that fool cancer cells

Antitumor antibiotics—interrupts DNA/RNA synthesis

Alkylating agents—cross links DNA-2 strands bind together, inhibiting cell division

Chemotherapy, cont.

Antimitotic agents—usually made from plant sources, prevents completion of mitosis

Topoisomerase inhibitors—prevents enzyme from copying and reattaching, causing DNA breakage and cell death

Miscellaneous—doesn’t fit anywhere else Combination

Total Body Surface Area

BSA, TBSA, PSA Height and weight Ht (cm) x wt (Kg) / 10,000 = TBSA

5’11’’ tall and weighs 186 pounds What is his TBSA?

Calculating TBSA

5’11’’ = 71 inches = 180.34 185# = 84.1 KG

180.34 X 84.4 10,000

BSA = 1.52

Scheduling and Administration

Schedule treatment every 3-4 weeks for the total (Course) of 6-12 months

Administration– PO or Im– Mostly given IV (CVL or pIV)– Intra-thecal– Intra-arterial– Intra-peritoneal– Intra-vesical

Extravasation

Irritants Vesicants Most important

nurse action is prevention

What do you do if an extravasation happens?

How does chemo work?

Cancer cells divide continously Chemo kills during cell division Chemo kills good cells as well as bad

cells– http://www.cancer.org/docroot/ETO/content/E

TO_1_2X_Chemotherapy_What_It_Is_How_It_Helps.asp

– http://www.cancer.org/docroot/ETO/content/ETO_1_4X_How_Does_Chemotherapy_Work.asp?sitearea=ETO

Side Effects of Chemotherapy

Immunosuppression Anemia Thrombocytopenia Alopecia Nausea and vomiting Mucositis

Alopecia

Hair loss is usually temporary and does reverse

Nausea and Vomiting Can continue for 5-7

days s/p chemotherapy

Give antiemetics Avoid spicy or rich

foods, strong smells, and extreme hot or cold liquids

Mucositis

Soft bristled toothbrush

Avoid toothpicks and dental floss

Avoid mouthwashes that contain alcohol

Do frequent mouth care

Give pain meds PRN

Immunosuppression

Nadir—lowest point in blood counts s/p chemo– Usually seen in 5-10 days

Neutropenia – WBC below 1000

Patient is at extreme risk for infection

Major dose limiting side effect of chemotherapy

Anemia

Hgb below 8—transfuse

S/S fatigue and SOB

Thrombocytopenia Decreased platelets Below 50,000—

bleeding precautions Below 20,000—high

risk Transfuse with

platelets Educate and protect

patient

Immunotherapy: Biological Response Modifiers

Stimulates the production of bone marrow

Cytokines—interferon, interleukins, epogen, G-CSF, GM-CSF

Hormonal Manipulation

Some hormones make homes-sensitive tumors grow more rapidly—so decreasing amount of hormone in body can cause tumor growth to slow.

Types– Agonists– Antagonists– Inhibitors

Gene Therapy

Experimental Has shown limited response rates, but

indicates potential for future treatment.

Targeted Therapy

Combination of gene therapy and biologic therapy to target specific cells– Examples: herceptin and gleevac

Most common side effect is allergic reactions

Oncological Emergencies Sepsis Disseminated intravascular coagulation Syndrome of inappropriate antidiurectic

hormone Spinal cord compression Hypercalcemia Superior vena cava syndrome Tumor lysis syndrome

Sepsis

Septic shock Life threatening

– 1st get blood cultures and urine culture– 2nd start antibiotics

DIC (70% mortality rate)

Blood clotting problem often caused by sepsis (gram negative infection) in cancer patients.

Release of clotting factors from cancer cells cause excessive abnormal clot formation in small blood vessels, which use up the clotting factors and platelets in the blood.

DIC, cont.

This leads to extensive bleeding. Clots are still there which can block

blood vessels and decrease blood flow to major organs.

Early treatment is to treat the cause and give anticoagulants

Late treatment is to control the bleeding and give cryoprecitated clotting factors

SIADH

Water is reabsorbed to excess by the kidneys and put into the systemic circulation

Increase in water causes a decrease in sodium levels (hyponatremia) and increased fluid retention

SIADH, cont.

May lead to seizures, coma, and death Treatment—

– Increase sodium intake– Restrict fluids (often 500 cc – 1 L/24h)– Drug therapy (demeclocycline)– Monitor serum sodium levels– Reduce or eliminate underlying cause

Spinal Cord Compression

Tumor directly enters the spinal cord or vertebrae

Collapse from tumor degradation of vertebrae bone

Early recognition is the key to treatment

Spinal Cord Compression, cont.

Treatment includes high dose corticosteroids to reduce swelling, radiation may be used to shrink tumor, surgery is an option, back or neck braces may be used to support the spinal column and decrease pressure on the spinal cord.

Hypercalcemia

Most often seen with bone mets Bone cancer causes release of calcium

into the bloodstream Decreased mobility and dehydration

worsen hypercalcemia Treatment includes hydration, monitor

serum calcium levels, and drugs to reduce calcium.

Superior Vena Cava Syndrome

SVC compressed or obstructed by tumor growth

Blockage of blood flow in the venous system of neck and upper trunk

S/S: facial swelling, distention of jugular veins, edema of hands and arms, dyspnea

Treatment: high dose radiation, possible surgical stint

Compression of the superior vena cava

Tumor Lysis Syndrome

Rapid destruction of tumor cells, releasing cell contents into the bloodstream faster than the body can eliminate them.

Best treatment: Prevention through– Hydration—(3000-5000 ml/24h) dilutes K+

level and increases kidney filtration rate– Diuretics– Drugs—allopurinol

Tumor Lysis

Treatment Failure

50% of people diagnosed with cancer are cured

Others live 5 years or longer Some have treatment failure and die Dying process is usually long, lasting

weeks or months. Care of the terminally ill patient.

Good bye, all done… study hard….