Section 9.3: Immunologic, Inflammatory, and Cellular Aberrations (Oncology)

Cellular Aberrations: Oncology

Oncology and immunology represent complex clinical areas frequently tested on the Philippine Nurse Licensure Examination (PNLE). Registered Nurses in the Philippines are expected to understand the molecular basis of cellular aberrations, implement rigorous safety protocols during chemotherapy and radiation, and provide compassionate, confidential care to patients with immunologic disorders in accordance with RA 11166 (Philippine HIV and AIDS Policy Act of 2018) and the Philippine Nursing Act of 2002 (RA 9173).

Cancer Pathophysiology

Cancer is characterized by uncontrolled cellular growth, invasion into surrounding tissues, and metastasis to distant sites, driven by genetic mutations in oncogenes and tumor suppressor genes.

• Benign vs. Malignant Tumors:

• Warning Signs of Cancer: The American Cancer Society utilizes the CAUTION mnemonic to educate patients on the early signs of cancer:
  • Change in bowel or bladder habits (e.g., persistent diarrhea, blood in stool, urinary retention).
  • A sore that does not heal (especially on the skin or oral mucosa).
  • Unusual bleeding or discharge (e.g., hemoptysis, hematuria, postmenopausal vaginal bleeding).
  • Thickening or lump in the breast, testicles, or elsewhere.
  • Indigestion or difficulty swallowing (dysphagia).
  • Obvious change in a wart or mole (e.g., changes in size, shape, color - ABCDE rules).
  • Nagging cough or hoarseness.

Chemotherapy Side Effects & Nursing Management

Chemotherapy involves the systemic administration of cytotoxic drugs to disrupt cancer cell division. Because these drugs target rapidly dividing cells, they also destroy healthy, rapidly dividing cells in the hair follicles, gastrointestinal tract, and bone marrow.

• Bone Marrow Suppression (Myelosuppression):
  1. Anemia: Characterized by low red blood cell counts, hemoglobin, and hematocrit.
     • Nursing Care: Monitor Hgb/Hct. Administer recombinant erythropoietin (epoetin alfa) as prescribed to stimulate RBC production. Schedule frequent rest periods to combat fatigue. Provide a diet rich in iron and vitamin B12.
  2. Thrombocytopenia: Platelet count $< 100,000/ ext{mm}^3$. Active bleeding risk increases significantly when platelets fall below $50,000/ ext{mm}^3$; spontaneous bleeding can occur below $20,000/ ext{mm}^3$.
     • Nursing Care: Implement Bleeding Precautions: Avoid intramuscular (IM) injections and venipunctures when possible. Use a soft-bristled toothbrush. Avoid flossing. Use an electric razor instead of a safety blade. Avoid rectal temperatures, suppositories, and enemas. Instruct the client to avoid blowing the nose forcefully. Administer stool softeners to prevent straining. Avoid aspirin and other NSAIDs. Monitor for petechiae, ecchymosis, hematuria, and occult blood in stools.
  3. Neutropenia: Characterized by a low white blood cell count, specifically an Absolute Neutrophil Count (ANC) $< 1,000/ ext{mm}^3$. An ANC $< 500/ ext{mm}^3$ indicates severe neutropenia, placing the patient at extreme risk for life-threatening opportunistic infections.
     • Nursing Care: Implement Neutropenic (Protective/Reverse) Precautions:
       • Place the client in a private room with positive-pressure airflow (HEPA filtration). Keep the door closed.
       • Enforce strict hand hygiene for everyone entering the room.
       • Strictly prohibit sick visitors and staff members.
       • Omit fresh flowers, potted plants, and standing water from the room, as they harbor Pseudomonas aeruginosa and fungi.
       • Instruct the patient to consume a low-microbial diet: avoid raw fruits and vegetables (only cooked produce or fruits that can be completely peeled are allowed, though many protocols ban all raw produce), raw or undercooked meats, raw eggs, and unpasteurized dairy. Avoid cold cuts and buffets.
       • Avoid invasive procedures (e.g., urinary catheterization) unless absolutely necessary.
       • Oncology Emergency: Monitor the patient's temperature every 4 hours. A temperature of $\ge 38.0^\circ ext{C}$ ($100.4^\circ ext{F}$) is a medical emergency. The neutropenic patient lacks the white blood cells to produce classic signs of infection (like pus or swelling); fever may be the only sign of impending septic shock. If fever occurs, immediately obtain prescribed blood cultures (two sets) and start empirical broad-spectrum IV antibiotics within 1 hour.
• Vesicant Extravasation Management:
  • Vesicants (e.g., doxorubicin, vincristine, paclitaxel) are chemotherapeutic agents that cause severe tissue damage, blistering, and necrosis if they leak into the subcutaneous tissue.
  • Assessment: Monitor the IV site for swelling, erythema, burning, pain, induration, and lack of blood return.
  • Priority Action Sequence:
    1. Immediately stop the infusion to prevent further drug spillage.
    2. Do not remove the IV cannula immediately. Disconnect the tubing and attach a sterile syringe to the cannula.
    3. Aspirate any residual drug and blood from the cannula.
    4. Administer the specific antidote (e.g., sodium thiosulfate or hyaluronidase) through the cannula, if prescribed.
    5. Remove the cannula.
    6. Apply a warm or cold compress as indicated for the specific drug (e.g., cold compresses for doxorubicin to restrict spread; warm compresses for vincristine to promote absorption and dilution).
    7. Elevate the affected extremity to promote lymphatic drainage.
    8. Document the site appearance, estimated volume extravasated, and actions taken; notify the physician.

Radiation Therapy Care

Radiation therapy uses high-energy ionizing radiation to destroy cancer cells by damaging their DNA.

• External Beam Radiation (Teletherapy): The radiation source is outside the patient. The patient is not radioactive and poses no risk to others.
  • Skin Care Guidelines (Irradiated Area):
    • Wash the skin in the treated area gently with lukewarm water and mild, non-perfumed soap (if permitted by the oncologist). Pat dry with a soft towel; do not rub.
    • Do not wash off the radiation ink markings on the skin, as they outline the precise target field.
    • Avoid applying lotions, creams, perfumes, deodorants, powders, or cosmetics to the irradiated area unless specifically prescribed by the radiation team.
    • Wear loose-fitting, soft cotton clothing over the site to avoid friction.
    • Avoid exposing the irradiated skin to direct sunlight, heat lamps, hot water bottles, or ice packs.
• Internal Radiation (Brachytherapy): A radioactive source (implant, seed, or ribbon) is placed directly into or next to the tumor (e.g., cervical, prostate cancer). The patient is radioactive and emits radiation while the source is active.
  • Safety Rules (Time, Distance, Shielding):
    • Time: Limit direct contact with the patient to a maximum of 30 minutes per nurse per 8-hour shift.
    • Distance: Maintain a distance of at least 6 feet from the bed when not providing direct care.
    • Shielding: Wear a lead apron when providing direct care. Wear a film badge (dosimeter) to measure cumulative radiation exposure (never share the badge or wear it outside the hospital).
    • Patient Placement: Assign the patient to a private room with a private bathroom. Place a "Caution: Radioactive Material" sign on the door and keep the door closed.
    • Visitor Restrictions: Limit visitors to 30 minutes per day. Visitors must maintain a 6-foot distance from the patient. No visitors under the age of 18 or pregnant women are permitted.
    • Staffing: Pregnant nurses or those planning to conceive must not be assigned to care for patients receiving brachytherapy.
  • Dislodged Implant Management:
    1. Do not touch the radioactive source with bare hands or gloves.
    2. Immediately use long-handled lead forceps (which must always be kept in the patient's room) to pick up the dislodged implant.
    3. Place the implant immediately into the lead-lined container (the "pig") located in the patient's room.
    4. Notify the radiation oncologist and the hospital radiation safety officer immediately.
    5. Instruct the patient to remain in bed and do not allow them to leave the room.

---

Immunologic and Inflammatory Disorders

HIV and AIDS

Human Immunodeficiency Virus (HIV) is a retrovirus that infects and destroys CD4+ T-helper cells, leading to progressive immune system collapse and susceptibility to opportunistic infections.

• Progression from HIV to AIDS:
  • A normal CD4+ T-cell count ranges from 500 to 1,500 cells/mm³.
  • An HIV-positive patient is diagnosed with Acquired Immunodeficiency Syndrome (AIDS) when their CD4+ count falls below 200 cells/mm³ OR they develop an AIDS-defining opportunistic infection (regardless of the CD4+ count).
  • Common Opportunistic Infections (OIs):
    • Pneumocystis jirovecii Pneumonia (PJP): Presents with dry cough, fever, and progressive dyspnea.
    • Kaposi's Sarcoma (KS): Vascular tumor presenting as painless, hyperpigmented purple-brown skin lesions.
    • Esophageal Candidiasis: Fungal infection causing severe dysphagia.
    • Tuberculosis (TB): Caused by Mycobacterium tuberculosis; highly prevalent in the Philippines and a leading cause of death in AIDS patients.
• Antiretroviral Therapy (ART) Adherence: ART involves a combination of drugs (usually three drugs from two different classes) to suppress viral replication, allow CD4+ counts to recover, and prevent disease progression.
  • Adherence Education: Educate the patient that adherence must be at least 95% or higher (missing no more than 1–2 doses a month) to maintain viral suppression and prevent the virus from mutating and developing drug resistance.
• Philippine HIV and AIDS Policy Act of 2018 (RA 11166):
  • This law replaced RA 8504. It updates policies on HIV/AIDS prevention, treatment, and care in the Philippines.
  • Voluntary Testing & Consent: HIV testing must be voluntary. The age of consent for testing is 15 years old. Adolescents aged 15 to 17 can access HIV testing, counseling, and treatment without parental consent. For children under 15 who are pregnant, married, or high-risk, consent is obtained from the child or a social worker if parents are unavailable.
  • Pre- and Post-Test Counseling: Mandatory for all individuals undergoing HIV testing to provide psychological support and risk-reduction education.
  • Confidentiality: The law strictly protects the confidentiality of HIV status. Disclosure of a patient's HIV status without written consent is a criminal offense, except in limited cases (e.g., subpoena, partner notification when risk of transmission is high).

Systemic Lupus Erythematosus (SLE)

Systemic Lupus Erythematosus is a chronic, progressive, multi-system autoimmune inflammatory disease characterized by the production of autoantibodies against self-antigens (especially Antinuclear Antibodies [ANA], anti-double-stranded DNA [anti-dsDNA], and anti-Smith antibodies).

• Pathogenesis: Autoantibodies bind to self-antigens, forming immune complexes that deposit in blood vessels, basement membranes, and connective tissues of various organs (joints, skin, kidneys, heart, lungs). This activates the complement cascade, causing inflammation, ischemia, and tissue necrosis.
• Clinical Manifestations:
  • Butterfly (Malar) Rash: A classic, dry, red, maculopapular rash across the bridge of the nose and cheeks. It is highly photosensitive (aggravated by exposure to ultraviolet/sun light).
  • Polyarthralgia or arthritis (joint pain and swelling, especially in small joints).
  • Fever, fatigue, and weight loss during flare-ups.
  • Raynaud's phenomenon (vasospasm of digits in response to cold).
• Lupus Nephritis: A severe complication where immune complexes deposit in the renal glomeruli, leading to glomerulonephritis and potential renal failure.
  • Nursing Monitoring: Monitor the patient's blood pressure closely (hypertension accelerates renal damage). Monitor kidney function: Serum Creatinine, Blood Urea Nitrogen (BUN), and 24-hour urine for protein (proteinuria $> 0.5 ext{ g/day}$ or presence of cellular casts indicates nephritis). A renal biopsy is the gold standard for staging lupus nephritis.
• Pharmacotherapy: Corticosteroids (e.g., Prednisone):
  • Corticosteroids are used to suppress the immune system and control inflammation during acute exacerbations.
  • Side Effects: Hyperglycemia, osteoporosis (calcium/Vit D supplements needed), fluid retention and edema, hypertension, increased susceptibility to infection (immunosuppression), peptic ulcer disease, Cushingoid features (moon face, buffalo hump, truncal obesity), cataracts, and mood swings.
  • Critical Patient Education: Never discontinue corticosteroids abruptly. Exogenous steroids suppress the hypothalamic-pituitary-adrenal (HPA) axis, causing the adrenal glands to stop producing endogenous cortisol. Abrupt withdrawal can precipitate an acute, life-threatening adrenal crisis (Addisonian crisis), characterized by profound hypotension, hyponatremia, hyperkalemia, hypoglycemia, and cardiovascular collapse. Steroids must be tapered slowly under medical supervision.