Cancer Pathophysiology Nursing Notes

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CANCER Week 3: Ch. 12-14 Objectives:  Define cancer and discuss methods for naming and classifying tumors  Describe characteristics of the cancer cell and the mechanism involved in metastasis  Discuss diagnosis, staging, and treatment of cancer  List 10 oncologic emergencies in the cancer patient  Compare childhood and adult cancers CANCER  Derived from Greek word for crab, karkinoma  “Cancer” refers to a BENIGN benign)  Cancer is not one disease GROW SLOWLY  Many cancers can be WELL-DEFINED CAPSULE and treatment CLASSIFICATION AND  Tumors named (initially) which they arise 

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GROW RAPIDLY NOT ENCAPSULATED

NOT INVASIVE

INVASIVE

WELL DIFFERENTIATED

POORLY DIFFERENTIATED

LOW MITOTIC INDEX

HIGH MITOTIC INDEX

Benign tumors DO NOT METASTASIZE CAN SPREAD DISTANTLY o Include the suffix (METASTASIS) o Can be life cause bleeding, erodes through vessel) o Can progress to cancer o Examples:  Hemangioma – benign tumor of blood vessels  Meningioma – benign tumor of the meninges

malignant tumor (vs – many different types cured with early detection NOMENCLATURE according to tissues from

“oma” threatening (grow too big,

Malignant tumors o Carcinomas – arise from epithelial tissue o Adenocarcinomas – arise from glandular or ductal epithelium  Ex: malignant tumor from breast glandular tissue (mammary adenocarcinoma) o Sarcoma – arise from connective tissue o Lymphoma – arise from lymphatic tissue o

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MALIGNANT

Leukemia – arise from blood-forming cells

Carcinoma in situ (CIS) o Pre-invasive epithelial malignant tumor of glandular or squamous cell origin o LOCALIZED to epithelium only o Has not broken thru basement membrane or invaded the surrounding stroma (an early-stage cancer) o *Common locations:  Stomach, endometrium, breast, large bowel  Cervix, skin, mouth, esophagus, bronchus

CHARACTERISTICS OF CANCER CELLS  How they proliferate/survive; behave differently from normal cells 

Transformation  Normal cell becomes cancer cell

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Autonomy  Cancer cells gain independence from normal cellular controls (part of transformation process)

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Anaplasia (hallmark of cancer cells via microscope) o Abnormal cell structure – Loss of cellular differentiation/organization, marked inc in nuclear size, loss of normal tissue structure, and evidence of ongoing proliferation Anchorage independent  Will divide even outside the human body Immortal  Unlimited lifespan!  HeLa cells CANCER STEM CELLS  Exist in hematologic and solid tumors  Share characteristics with normal stem cells o Self replicate – Cell division creates new stem cells o Differentiation – Multiple different cell types  Critical to cancer’s ability to recur and metastasize TUMOR MARKERS  Biological markers  Produced by cancer cells  Can be found in CSF, blood, urine or in tumor cells o Examples:  PSA blood assay for prostate CA  Carcinoembryonic antigen (CEA)  Blood assay for pancreatic, GI, lung, breast CA  Detection in other body fluids related to metastasis *Tumor markers are used to:  Screen and identify individuals at high risk for certain types of cancer  Diagnose specific types of tumors  Observe clinical course of cancer (Ex: would expect dec CEA levels after tx of colon CA) ETIOLOGY   

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Carcinogens o Injury to cell with exposure o Latent period Chemical o Asbestos o Cigarettes Radiation o X-rays o UV light o Nuclear radiation Infection o Chronic inflammation o Chronic suppression/stimulation of immune system  Ex. Papillomavirus (HPV causes cervical CA), HIV, Heliobacter pylori Irritants o Pipe smoking o GENETICS o Cancer cells develop because of gene mutations  Changes in DNA mutations, DNA/histone chemical modification, micro-RNA expression o Two types of genetic mutation:

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Germ-line Acquired

o CA is disease of aging o Genetic mutations occur over time o 4 to 7 mutations lead to CA o  GENES LINKED TO CA  mutations in these genes leads to cancer o Oncogenes (accelerate proliferation) o Tumor-suppressor genes (antioncogenes) (‘put the brakes on’)  BRCA1 & BRCA2 (breast and ovarian) o METASTASIS  defining characteristic of cancer  Spread of cancer from a primary site of origin to a distant site o Inefficient process o Most cancer cells cannot metastasize  Contributes to pain and suffering of cancer pt  Major cause of death  Occurs via lymph, blood, seeding, and transplantation o  Overview: o Detachment and invasion o Survival and spread in circulation o Selective adherence o Escape from circulation o  1) Direct invasion of contiguous organs Known as local spread  2) Metastases to distant organs via lymphatics and blood (direct/continuous spread)  3) Metastases by way of implantation o O DIAGNOSIS  Detection through screening, physical exam, and symptoms  Comprehensive medical history and physical exam  Diagnostics to further evaluate: o Ex: CXR, CT, MRI, U/S  Definitive diagnosis through tissue pathology  BIOPSY o Is it malignant or benign? If malignant, what cell type? (i.e. squamous, epithelial, small cell) o O STAGING o  Involves the size of the tumor, degree to which it has invaded, and extent of spread  Stage 1 – Cancer is confined to its organ of origin  Stage 2 – Locally invasive  Stage 3 – Regional structures (lymph nodes)  Stage 4 – Distant sites o o o TNM System (know how to stage) 

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o o o o O PAIN o o o

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CLINICAL MANIFESTATIONS OF CANCER Little or no pain is associated with early stages of malignancy Influenced by fear, anxiety, sleep loss, fatigue, and overall physical deterioration Mechanisms:  Pressure, obstruction, invasion of sensitive structures, stretching of visceral surfaces, tissue destruction, and inflammation

o FATIGUE o Subjective clinical manifestation o Tiredness, weakness, lack of energy, exhaustion, lethargy, inability to concentrate, depression, sleepiness, boredom, and lack of motivation o Suggested causes:  Sleep disturbance, biochemical changes from circulating cytokines, secondary to disease and treatment, psychosocial factors, level of activity, nutritional status, and environmental factors o CACHEXIA o Most severe form of malnutrition o Present in 80% of cancer patients at death o Includes:  Anorexia  Early satiety  Weight loss  Anemia  Asthenia  Taste alterations  Altered protein, lipid, and carbohydrate metabolism o ANEMIA o A decrease of hemoglobin in the blood o Mechanisms:  Chronic bleeding resulting in iron deficiency, severe malnutrition, medical therapies, or malignancy in blood forming organs

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LEUKOPENIA & THROMBOCYTOPENIA (dec WBCs, dec platelets) o Direct tumor invasion to the bone marrow causes leukopenia and thrombocytopenia o Chemotherapy drugs are toxic to bone marrow o INFECTION o Risk increases when the absolute neutrophil and lymphocyte counts fall (inverse relationship) o PARANEOPLASTIC SYNDROMES o Symptom complexes that cannot be explained by the local or distant spread of the tumor or by the effects of hormones released by the tissue from which the tumor arose o     

O TREATMENT  CHEMOTHERAPY Began with mustard gas in WWII Now extensive cancer chemo “cocktails” Targets vulnerability of cancer cells Usually given in combinations Toxic to normal AND abnormal cells

o O O O O O O O O O O CHEMOTHERAPY O O CLASSIFICATION: (based on what it does) Cell cycle-phase specific o Antimetabolites o Plant Alkaloids o Cell cycle nonspecific o Alkylating Agents o Antitumor antibiotics o Hormones o O TYPES: Induction chemotherapy o 1st chemotherapy agent given o Accepted as best treatment o Often given in toxic doses Neoadjuvant o Given PRIOR to other treatments o Ex – To shrink tumor prior to surgery Adjuvant o Given AFTER primary treatment (i.e. surgery) of cancer o Lowers risk of recurrence  Salvage o Trying to buy the pt some time; no cure o o

CHOP = Chemotherapy Regime for Lymphoma  C: Cytoxan® (cyclophosphamide)

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H: Adriamycin® (hydroxy doxorubicin) O: vincristine (Oncovin®) P: Prednisone o o Given in 21 day cycles, usually 6-8 cycles  Day 1: C, H, O given IV; P given PO  Days 2-5: P given PO  Days 6 – 21: rest o O TREATMENT – RADIATION Ionizing radiation o Damages cells by imparting enough ionizing radiation to cause molecular damage, esp to DNA-killing cancerous cells o Causes irreversible damage to normal cells  Lifetime radiation dosage (can only have a certain amt) Brachytherapy o Seed implants (prostate CA) O O TREATMENT – SURGERY  Surgery o Biopsy and lymph node sampling  Sentinel nodes o Debulking surgery (part but not all) o Palliative surgery (buying time) o  Careful! To achieve a cure… o Must achieve adequate surgical margins (get it all) o Must place needle tracks and biopsy incision scars (that may be contaminated with cancer cells) carefully so they can be removed in subsequent incisions o Must avoid the spread of cancer cells during surgical procedures o Must obtain adequate tissue specimens to confirm the diagnosis o O TREATMENT – IMMUNOTHERAPY  Theoretically, antitumor responses can selectively eliminate cancer cells while sparing normal cells  Immune memory is long lived  Numerous immunologic mechanisms are capable of rejecting different types of cancer Biologic response modifiers (BRMs) o  Other forms of immunotherapy: o Interferon administration o Antigens o Effector cell lymphokines o Monoclonal antibodies o    

O SIDE EFFECTS OF CANCER TREATMENT Gastrointestinal tract – N/V Bone marrow suppression – Decreased platelets and WBCs Hair and skin o Hair loss (chemo agents target rapidly growing cells in general) o Skin dryness, breakdown Reproductive tract o Decreased fertility o Gonadal failure o Early menopause

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O Pain

DISEASE AND TREATMENT COMPLICATIONS

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Fatigue Cachexia Anemia Leukopenia and thrombocytopenia Infection

o O ONCOLOGIC EMERGENCIES (LIFE-THREATENING)  Metabolic o Disseminated Intravascular Coagulation (DIC) o Thrombocytopenia o Sepsis/Septic Shock (d/t immunosuppression) o Tumor Lysis Syndrome o Hypercalcemia o Syndrome of Inappropriate Antidiuretic Hormone (SIADH) (hypoNa+) o Anaphylaxis o  Structural o Increased ICP o Spinal Cord Compression (paralysis symptoms) o Superior Vena Cava Compression o Cardiac Tamponade o Malignant Pleural Effusions o O CHILDHOOD CANCERS  Most common childhood cancers are leukemias, sarcomas, and embryonic tumors o Embryonic tumors:  Originate during uterine life  Usually diagnosed before age 5  Immature embryonic tissue unable to mature or differentiate into fully developed cells  Commonly named with the term “blast” (i.e. an immature cell)  + Blast  BAD on CBC! (means leukemia of some type) o  Most originate from the mesodermal germ layer o The mesodermal layer gives rise to connective tissue, bone, cartilage, muscle, blood, blood vessels, gonads, kidneys, and the lymphatic system o   

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O CANCER – ADOLESCENTS AND YOUNG ADULTS 2% of all invasive cancers Malignancy rate in 15- to 29-y.o. is 3x’s higher than that in children