NUR 201Module D – Oncology

Pathophysiology

Cancer is a disease process that begins when and abnormal cell is transformed by the genetic mutation of the cellular DNA. This abnormal cell forms a clone and begins to proliferate abnormally, ignoring growth-regulating signals in the environment surrounding the cell.

The cells infiltrate surrounding tissues and gain access to lymph and blood vessels, which carry the cells to other areas of the body.

Benign and cancerous growths are classified and named by tissue of origin.

Characteristics of Benign Cells: Demonstrate continuous or inappropriate cell growth Show Specific morphology Have a smaller nuclear cytoplasmic ratio Perform differential functions Adhere tightly together Are nonmigratory – localized Grow in an orderly manner Well differentiated – resemble cells they came from End in “oma” Do not cause damage - the only problems that occur are by growth

Characteristics of Malignant Cells: Demonstrate rapid or continuous cell division Show anaplastic morphology Have a larger nuclear cytoplasmis volume Lose some or all differentiated functions – do not resemble the cells they came from Adhere loosely together Are able to migrate Grow by invasion Are not contact inhibited

Carcinogenesis Process of changing a cell with a normal appearance and function into a cell with

malignant characteristics. Called malignant transformation, occurs through 4 steps:

o Initiation - Carcinogens initiate mutational changes in a cell’s genes. It is an irreversible event that leads to cancer development. Once a cell has been initiated it can become a cancer cell if the cellular changes are enhanced by

promotion. 1 cancer cell is not significant unless it divides. If it can divide wide spread metastasis can occur. There can be a latency period when the cells do not divide and grow-can range from months to years. Irreversible event. Carcinogens change genetic structure of DNA.

o Promotion - Promoters are substances that promote or enhance cell growth and shorten the latency period. Promoters may be hormones, drugs or industrial chemicals, asbestos, hair dye. ALWAYS follows initiation.

o Progression - When cancer cells have grown into a tumor. A 1 cm tumor has at least 1 billion cells in it. Then the tumor must establish its own blood supply. The orginal tumor formed is called the primary tumor. It is identified by the tissue from which it first arose (parent tissue). Cells get nourishment and increase in malignant activity.

o Metastasis - Cancer cells can move from their original location by breaking off from the original group and making more colonies. When it spreads they are called metastatic or secondary tumors. Even if it has metastasized to lung from original breast, it is still called breast cancer in the lung.

Proliferative Patterns

During the lifespan, various tissues normally undergo periods of rapid or proliferative growth that must be distinguished from malignant growth activity.

Several patterns of growth exist: Hyperplasia Metaplasia Dysplasia Anaplasia Neoplasia

Cancerous cells are described as malignant neoplasms: They demonstrate uncontrolled cell growth that follows no physiological demand

(neoplasia)

Characteristics of Malignant Cells Nuclei are large and irregularly shaped Chromosomes are more fragile Mitosis (cell division) occurs much more rapidly

o As cells divide – more oxygen and glucose are needed Cell membranes altered, which affects fluid movement

o Contain TSA (Tumor Specific Antigen) and PSA (Prostate Specific Antigen) – Which are useful in measuring the extent of disease and tracking the course of

illness during treatment and relapses. TSA and PSA develop over time as the cells become less differentiated.

o Contain less fibronectin (a cellular cement) therefore, cells are less cohesive and do not adhere to other cells readily

Invasion and Metastasis -Malignant cells have the ability to spread to other body parts and organs by invasion and metastasis.

Invasion – growth of the primary tumor into the surrounding host tissues – which occurs in several different ways

Metastasis – Dissemination or spread of malignant cells from the tumor to distant sites by direct spread of tumor cells to body cavities or through lymphatic or blood circulation

Lymphatic – Most common – Tumor emboli enter lymph channels through interstitial fluid which communicates with lymphatic fluid. Malignant cells can also penetrate lymphatic vessels by invasion. After entering the lymphatic system, the malignant cells either lodge in the lymph nodes or pass between the lymphatic and venous circulations

Hematogenous – Blood stream – directly related to vascularity of the tumor Local Seeding – Tumor sheds cells which then travel through the body and plants those

cancerous “seeds”

Tumors that arise in areas with rapid or extensive lymphatic circulation are at VERY high risk of metastasis. Example: Breast Cancer

Detection and PreventionAvoid known or potential carcinogens such as tobacco, asbestos; and avoid associated factors such as sun exposure.

TISSUES ASSOCIATED WITH THE GREATEST RISK FOR CANCER ARE THOSE WITH DIRECT CONTACT WITH TOBACCO SMOKE OR DIP.

Primary – Decrease risk of disease through health promotion strategies Avoid carcinogens Dietary and lifestyle changes Sunscreen, HPV vaccine, etc.

Secondary – promotes screening and early detection Breast exams Colonoscopy

Tertiary – prevention of re-occurrence

Teach the mnemonic CAUTION:C – Change in Bowl or Bladder A – A lesion that does not healU – Unusual bleeding or dischargeT – Thickening or lump in breast or elsewhereI – Indigestion or difficulty swallowingO – Obvious changes in wart or moleN – Nagging cough or persistent hoarseness

Grading and Staging – To help standardize cancer diagnosis, prognosis and treatment, classifications were developed.

Grading – seeks to define the type of tissue from which the tumor cells originated and the degree of differentiation.Grading of a tumor classifies cellular aspects of the cancer. Some tumors are more malignant than others in their aggressiveness and sensitivity to treatment. Cells that are a high grade mean they are more malignant, rapid growth. The cells may not resemble the parent cell.

Grades I – IV: Grade I – well differentiated, closely resemble tissue of origin and more easily treated Grade IV – do not clearly resemble the tissue of origin in structure or function,

undifferentiated, more aggressive, less responsive to treatment

Staging – Determines size of tumor and existence of local invasion and distant metastasis. Staging classifies clinical aspects of the cancer and determines the exact location and degree of metastasis present at diagnosis. Tumor stage dictates prognosis and influences therapy.

There are three ways to stage:o Clinical staging - assess patient’s signs and symptoms, may do biopsyo Surgical staging determines size, number of sites and degree of metastasis by

inspection at surgery.o Pathological staging is most definitive. The tumor size, number of sites and

degree of metastasis.

Management

Three types: Cure – complete eradication of malignant disease Control – Prolong survival and containment of cancerous growth Palliation – Relief of signs and symptoms, pain

Healthcare team and family must be realistic and have a clear understanding of treatment options and goals

SurgeryMay be diagnostic, primary, prophylactic, palliative, or reconstructive

Diagnostic surgery: Obtain a tissue sample for analysis of cells suspected to be malignant. In most cases, the biopsy is taken from the actual tumor but in some instances it may be necessary to biopsy lymph nodes near the tumor

Excisional Diagnostic Surgery – Most commonly used for easily accessible tumors of the skin, breast, upper and lower GI, and upper respiratory tract. In many cases, the surgeon can remove the entire tumor as well as the surrounding marginal tissues

Incisional Diagnostic Surgery – Performed when tumor is too large for removal. In this case, a wedge of tissue from the tumor is removed for analysis.

Excisional and Incisional Approach – Often performed through endoscopy Needle – Aspiration of tissue fragments through needle which is guided with

xray/CT/MRI/Ultrasound. Performed to sample suspicious masses that are easily accessible, such as a growth in the breast, thyroid, lung, liver, kidney.

o Outpatient basiso Less pain and discomfort

o Surrounding tissues disturbed only minimally o Decreases chances of seeding from occurring

Surgery as primary treatment – Goal is to remove entire or as much as is feasible (removing surrounding tissues and lymph nodes)

Local and Wide Excisions Local Excisions

o Outpatiento Warranted when mass is smallo Involves removal of both the mass and small margin of normal tissue that is

easily accessible Wide or Radical Excisions

o Removal of tumor, lymph nodes, adjacent involved structures and surrounding tissues that may be at increased risk for spread

o Can result in disfigurement and altered functioning necessitating rehabilitation or reconstructive procedures

Salvage Surgery – Uses and extensive approach to treat local reoccurrence of a cancer after use of less invasive primary approach

o Example: Mastectomy after primary lumpectomy

Once surgery is complete, one or more other (adjuvant) treatments may be used to increase likelihood of destroying remaining cancer cells. However, if treated early, some cancer may be considered cured (skin and testicular)

Surgery as prophylactic treatment – Removing non-vital organs at increased risk of developing cancer. Examples include colectomy, mastectomy, oophorectomy

Surgery as palliative treatment – When cure is not possible, the goals of treatment are to make the patient as comfortable as possible and promote quality of life

Performed to relieve complications of cancer such as ulceration, obstruction, hemorrhage, pain, and malignant effusion.

Surgery as reconstructive treatment – May follow curative or radical surgery to improve function of for a cosmetic approach

Nursing care during surgery: General perioperative care Education and emotional support Chemo and radiation therapy weaken the immune system – watch for infection,

impaired wound healing, altered pulmonary and renal function, and DVT

Radiation TherapyUsed for:

Curing cancer Thyroid carcinomas Localized cancer of head and neck Cancer of uterine cervix Controlling malignant disease when tumor can’t be surgically removed – can be used to

decrease the size of the tumor to enable surgical resection May be used prophylactically to prevent spread of primary cancer to a distant area Palliative relief – Reduce signs and symptoms of metastatic disease when cancer has

spread to brain, bone, or soft tissue

Radiosensitive tumor – one that can be destroyed by a dose of radiation that still allows for cell regeneration in the normal tissue; Well oxygenated cells tend to be more sensitive to radiation as well.

Lethal tumor does is one that will eradicate 95% or more of the tumor yet preserve normal tissue

Tumors shrink from the outside inward

Administration: Teletherapy – External beam radiation – Most commonly used

o Through computerized programs an invisible beam of highly charged electrons is programmed to penetrate the body and target a tumor with pinpoint accuracy

o Depending on the size/shape/location – different energy levels are generated to produce a carefully shaped beam that will destroy the targeted tumor yet spare the surrounding healthy tissue and vital organs in an effort to reduce the treatment toxicities for the patient

Brachytherapy – Internal radiationo Can be temporary or permanent

Temporary – can be delivered as a high dose for a short period of time or low dose for more extensive periods of time. Advantages include:

Shorter treatment time Decreased exposure to personnel Outpatient procedure for several days

o Delivers high dose of radiation to a localized areao The specific radioisotope for implantation is selected on the basis of its half lifeo Can be implanted by means of needles, seeds, beads, or catheters into body

cavities (vagina, abdomen), pleural or interstitial compartments (breast, prostate)

Intraluminal brachytherapy – involves insertion of catheters into the lumens of organs so that the radioisotope can be delivered as close to the tumor as possible.

o HDR – High Dose Radiation - Outpatiento LDR – Low Dose Radiation – Requires hospitalization as the patient is treated

over several days. Nursing care during this time includes: Bed Rest for 72 hours Log rolled to prevent displacement Foley catheter to keep bladder empty Low residue diet Antidiarrheal to prevent bowel movements which could displace the

isotopes Visitors must limit their time and proximity spent with the patient to

decrease the risk of radiation exposure Interstitial Brachytherapy – consist of seeds, needles, or small catheters positioned to

provide local radiation and are infrequently dislodges

With internal radiation, the farther away the source of radiation is, the lower the dosage delivered to the tumor cells.

Radiation Toxicity Localized to the area being treated Toxicity may be increased if chemo is administered along with radiation Acute local reactions occur when normal cells in the treatment area are also destroyed

and cellular death exceeds cellular regeneration Tissues affected are those that proliferate rapidly. EX: Skin, epithelial lining of GI tract,

including oral cavity, bone marrow, hair cells

Side Effects: Altered skin integrity – Can include alopecia (hair loss); Skin reactions are identified and

graded by severity ranging from erythema and dry desquamation (flaking of the skin) to moist desquamation(dermis exposed, skin oozing serous fluid) and potentially ulceration

Alteration in oral mucosa – o Stomatitis – Inflammation of oral tissueso Xerostomia – Dryness of the moutho Entire GI tract may be involved – esophageal irritation with chest pain,

dysphagia, nausea, vomiting, diarrhea, change/loss of tasteo decreased salivation, anorexia may occur if the stomach is in the irradiate field

Bone marrow – If sites containing bone marrow (iliac crest, sternum) are included in the radiation field, the following may result:

o Anemia (Decreased RBCs)o Leukopenia (Decreased WBCs)o Thrombocytopenia (Decreased platelets)o If these occur – the patient is then at an increased risk of bleeding and infection

Systemic Side Effects include Fatigue, malaise, anorexia Severe late effects (months to years after treatment) may effect heart, lungs, kidneys,

CNS, and bladder

Nursing management in Radiation Therapy Assess skin/oropharyngeal mucosa regularly Assess Nutritional Status Assess General feeling of well being If systemic S/S occur such as weakness and fatigue the nurse explains that these S/S are

a result of the treatment and do not represent the deterioration or progression the disease

Protecting Caregivers When the patient has a radioactive implant in place the nurse and other HCPs need to

protect themselves as well as the patient from the effect of radiation Patients receiving internal radiation emit radiation, therefore contact is guided by:

o Principles of timeo Distanceo And, Shielding

Safety Precautions Include:o Assigning a private roomo Posting notices about radiation safety precautionso Prohibiting visits by children or pregnant womeno Limiting visits to 30 minutes daily and making sure visitors remain at a 6 foot

distance from the patient at all timeso Having staff members wear dosimeter badgeso Making sure that pregnant staff members are not assigned to patient’s care

Chemotherapy Antineoplastic agents are used in an attempt to destroy tumor cells by interfering with

cellular functions including replication Used to treat systemic disease rather than just localized lesions that are amendable to

surgery or radiation May be combined with surgery, radiation, or both to reduce tumor size preoperatively

(neoadjuvant), destroy any tumor cells postop. (adjuvant), or to treat some forms of leukemia or lymphoma (primary)

Cell Kill and Cell Cycle Each time a tumor is exposed to a chemo agent a percentage of tumor cells is destroyed Repeated doses are necessary over a prolonged period of time to achieve regression of

the tumor Eradication of 100% of the tumor is almost impossible, instead the goal of treatment is

eradication of enough of the tumor so the remaining tumor cells can be destroyed by the body’s immune system.

Active proliferating cells are most sensitive to chemo. Nondividing cells – capable of future proliferation are least sensitive and potentially dangerous. These cells must be killed to eradicate the cancer.

o Repeated cycles of chemo or sequencing of multiple chemo agents are used to kill more tumor cells by destroying the nondividing cells as they begin active cell division

Classification of Chemo Agents – Classification to their relationship to the cell cycle

Cell Cycle Specific Agents – Chemo Agents that are specific to certain phases of the cell cycle

o These agents destroy cells that are actively reproducing by means of the cell cycle

o Most agents affect cells in the S phase – by interfering with DNA and RNA synthesis

o Other agents – vinca or plant alkaloids – are specific to the M phase and halt spindle formation

Cell Cycle Nonspecific Agents – Chemo agents that act independently of cell cycle phases

o Usually have prolonged effect on cells leading to cell death and damage

Many treatment plans combine cell cycle specific and cell cycle nonspecific to increase the number of vulnerable tumor cells killed during treatment

Administering Chemo – May be administered in hospital, outpatient center, or home by topical, oral, IV, IM, SubQ, arterial, intracavitary, and intrathecal routes. Route Depends on:

Type of agent Required dose Type, location, and extent of tumor being treated

Dosage – based primarily on the patient’s total body surface area, previous response to chemotherapy and radiation therapy, and function of major organ systems

Determined to maximize cell kill while minimizing impact on healthy tissues abd subsequent toxicities

Extravasation – additionally classified by their potential to damage soft tissue if they inadvertently leak from a vein

Consequences range from mild discomfort to severe tissue destruction Classified as nonvesicant, irritant, and vesicant

o Irritants – induce inflammatory reactions but cause no permanent damageo Vesicants – agents that if extravasation occurs:

Cause tissue necrosis Cause damage to underlying tendons, nerves, and blood vessels Sloughing and ulceration of the tissue progresses to tissue necrosis and

make be so severe that skin grafting may be necessary

Indication of Extravasation Include: Absence of blood return from IV Resistance to flow of IV fluid Burning, pain, swelling, redness at the site

IF EXTRAVASATION IS SUSPECTED, THE MEDICATION ADMINISTRATION IS STOPPED IMMENDIATEDLY, AND DEPENDING ON THE DRUG IS MADE TO ASPIRATE ANY REMAINING DRUG FROM THE SITE.

VESICANT CHEMO SHOULD NEVER BE ADMINISTERED IN HANDS AND WRISTS

PERIPHREAL ADMINISTRATION IS ONLY PERMITTED DURING SHORT TERM AND SHOULD BE GIVEN IN THE FOREARM WITH A SHORT, SOFT CATHETER.

Chemo Toxicity Can be acute or chronic

GI – Nausea, vomiting most common and can occur 24-48 hours after administration Nausea and vomiting involve multiple pathways therefore corticosteroids,

phenothiazines, sedatives, and antihistamines are helpful especially when used in combination with serotonin blockers to provided improved antiemetic protection

Hematopoietic – Most chemo agents cause myelosuppression (depression of bone marrow function) which results in:

Leukopenia (Decreased WBCs) Anemia (Decreased RBCs) Thrombocytopenia (Decreased platelets) Neutropenia (Decreased granulocytes)

Renal – Chemo agents can damage kidneys because of their direct effects during excretion and the accumulation of end products after cell lysis. Rapid tumor cell lysis after chemo results in:

Increased urinary excretion of uric acid In addition, intrcellular contents are released into circulation resulting in hyperkalemia,

hypocalcemia, and hyperphosphatemia Monitor BUN, serum creatinine, creatinine clearance, and F/E levels

Reproductive – Testicular and ovarian function can be affected by chemo agents resulting in possible sterilityWomen:

Normal ovulation Early menopause Or permanent sterility may occur

Men: Temporary or permanent azoospermia (absence of spermatozoa) may develop Banking of sperm is often recommended before treatment is initiated

Neurological : Chemo can affect the CNS, PNS, the cranial nerves, or a combination Can cause neurological damage with sensory alterations in hands and feet

o Tingling, prickling, numbness of the extremities; burning, freezing pain; sharp, stabbing, or electrical shock like pain; and extreme sensitivity to touch may occur

o Can lead to loss of DTR with muscle weakness, loss of balance/coordination, and paralytic ileus

Fatigue: A distressing side effect for most patients that greatly affects the quality of life can last for months after treatment

Nursing management during chemo treatment

F/E status: Anorexia, nausea, vomiting, altered tasted, mucositis, diarrhea, put patient at risk for nutritional and F/E disturbances

Assess patient’s nutritional and F/E status frequently Use creative ways to encourage adequate fluid and dietary intake

Infection/ Bleeding: Assessment and care address factors that would further increase patient’s risk.

Protecting caregivers –

Bone Marrow Transplant: Allogenic – from a donor other than the patient, may be a related donor or a matched

unrelated donor Autologus – from the patient Syngenic – From identical twin