Cancer Pathophysiology

• Cellular regulation involves all functions within cells to maintain homeostasis.
• This includes responding to extracellular signals and producing intracellular responses.

How Cancer Develops

• Cancer development relates to abnormal cell growth and differentiation.
• Cell differentiation: A less specialized cell becomes more specialized.

Abnormal Cell Growth

• Cell differentiation is the process where a less specialized cell becomes more specialized.
• Poor differentiation happens when specialized cells become less so.

Pathophysiology of Cancer

• Cancer arises from DNA mutations in cells.
• These mutations can stem from heredity, radiation, chemicals or spontaneous errors during DNA duplication.
• Cancer development involves:
  • Initiation.
  • Promotion.
  • Progression.

Oncogenes and Tumor Suppressor Genes

• Oncogenes promote cell growth and can trigger cancerous characteristics
• Tumor suppressor genes slow cell division.
• Tumor suppressor genes can become inactive by deletion or mutation.
• BRCA1/BRCA2 are linked to breast cancer if mutation occurs.

Characteristics of Normal vs. Cancer Cells

• Normal cells exhibit contact inhibition and develop differentiation.
• Cancer cells lack contact inhibition and are poorly differentiated (anaplastic).

Benign vs Malignant Neoplasms

• Benign neoplasms are localized, solid masses with well-defined borders, typically not life-endangering, and do not regrow after treatment.
• Malignant neoplasms involve aggressively growing tissue that doesn't respond to the body's homeostatic controls.
• Malignant neoplasms spread to other body parts and can lead to death if untreated.

Benign vs Malignant Characteristics

• Benign:*
• Local
• Cohesive
• Well-defined borders.
• Push other tissue out of the way
• Show slow growth
• Encapsulated.
• Easily removed.
• Does not tend to recur.
• Malignant:*
• Invasive.
• Non-cohesive.
• Stop at tissue border.
• Invade and destroy surrounding tissue.
• Fast growth.
• Metastasize to distant sites
• Can recur.

Grading and Staging Tumors

• Tumors classification is based on the anatomical site or tissue of origin e.g., Lymphoma is cancer of lymph nodes.
• Tumor grading assesses the amount of differentiation that occurs in a cell to its parent cell.
  • Grade 1 tumors are most similar with a better prognosis.
  • Grade 4 tumors have a poor prognosis.
• Tumor staging with the Tumor-Node-Metastasis (TNM) system determines the advancement of disease.
  • T: Tumor size.
  • N: Lymph Node involvement.
  • M: Presence or absence of distant Metastasis.

TNM System for Staging Breast Cancer

• T (Tumor Size):*
  • T-1: 0-2 centimeters.
  • T-2: 2-5 centimeters.
  • T-3: Greater than 5 centimeters.
  • T-4: Tumor has broken through skin or attached to chest wall.
• N (Lymph Node Status):*
  • N-0: Surgeon can't feel any nodes.
  • N-1: Surgeon can feel swollen nodes.
  • N-2: Nodes feel swollen and lumpy.
  • N-3: Swollen nodes located near collarbone.
• M (Metastasis):*
  • M-0: Tested nodes are cancer-free.
  • M-1: Tested nodes show cancer cells or micrometastasis.

Clinical Manifestations

• Signs and symptoms include pain, fatigue, anorexia, cachexia and infection.
• Additional signs and symptoms:
  • Palpable mass
  • Altered neurological function.
  • Hemorrhage or hematological alteration.

Risk Factors

• Cancer risk factors:
  • Age.
  • Race.
  • Genetics/heredity.
  • Exposure to chemicals.
  • Tobacco.
  • Alcohol.
  • Sun exposure.
  • Diet.
  • Viruses.
  • Bacteria.
  • Socioeconomic status.

Prevention and Detection

• Reduce specific risk factors.
• Use sunscreen.
• Smoking cessation.
• Balanced diet
• Health screenings.
• Follow occupational health and safety guidelines.
• Early Detection: Cancer's 7 Warning Signs
  1. Change in bowel/bladder habits.
  2. Non-healing sores.
  3. Unusual bleeding or discharge.
  4. Thickening of lump in breast or elsewhere.
  5. Indigestion or difficulty in swallowing.
  6. Obvious change in wart or mole.
  7. Nagging cough or hoarseness.

Diagnostics

• Biopsy
• Bone Marrow Aspiration
• Tumor Markers
• Lab Tests
• Incisional/Excisional biopsies
• Radiology Testing:
  • CT scan.
  • MRI.
  • Mammography.
  • X-ray
  • Ultrasound.

Complications of Cancer

• Hypercalcemia
• Malnutrition
• Infection.

Emergencies and Complications

• Superior Vena Cave Syndrome:*
• Compression of SVC by tumor
• Blood can't return to the heart
• Symptoms:
• Facial edema.
• Head/neck swelling.
• JVD.
• Headache, cough, seizure.
• Treatment:
• Raise head of bed.
• Radiation and chemotherapy.
• Possible surgery.
• ICU monitoring.
• Tumor Lysis Syndrome:*
• Increased number of tumor cells are killed rapidly & intracellular contents release.
• SEVERE electrolyte abnormalities:
• Hyperuricemia.
• Hyperphosphatemia.
• Hyperkalemia.
• Hypocalcemia.
• typically 24-48 hours after chemo.
• Symptoms:
• Muscle cramps and weakness.
• Diarrhea.
• Nausea.
• Vomiting.
• Treatment:
• Increase fluids.
• Give allopurinol.
• Monitor electrolytes closely.
• Spinal Cord Compression:*
• Symptoms:
• Back pain.
• Leg weakness and paresthesia.
• Bladder or bowel incontinence & retention.
• Treatment:
• Radiation.
• Corticosteroids.
• Increased Intracranial Pressure:*
• Symptoms:
  • Headache.
  • Confusion.
  • Unequal pupils.
• Treatment:
  • Corticosteroids.
  • Mannitol
  • May need intubation.
• Malignant Pericardial Effusion:*
• Cancer cells collect in pericardial sac leading to excess fluid.
• Places pressure on the heart.
• Symptoms:
• Respiratory issues.
• Dyspnea.
• Chest pain.
• Cough
• Fatigue.
• Poor prognosis.

Health Promotion and Prevention

• Eat: Healthy, plant-based diet and limit salt, fat intake.
• Avoid: Smoking, to prevent hyperplasia of bronchial cells and increased mucus production.
• Consume: Alcoholic beverages in moderation.
• Avoid: Risky lifestyles, such as recreational/IV drug use and unprotected sexual relations.
• Limit: Exposure to chemical/radiation exposure and take necessary protective precautions.
• Exercise: Daily exercise.

Interventions

• Treatment depends on location and origin of the cancer.
• Treatment options include:
  • Surgery.
  • Radiation.
  • Chemotherapy.

Goals of Cancer Treatment

• Curative
• Control
• Palliative

Treatment Options

• Focus treatment on destruction of cancer cells and prevention of continued abnormal growth.
• Treatment options includes:
  • Patient focused treatments
  • Genetic testing.
  • Medications, radiation, surgery and collaborative therapies.

Surgery

• Diagnostic: Biopsies (lymph nodes)
• Palliative: e.g De-bulking, diversion
• Cure and Control; Tumor margins
• Preventative

Chemotherapy

• Systemic or local CYTOTOXIC medications damage cell DNA.
• Used to cure, control progression or as a palliative measure.
• Selected based on type of cancer and effect on stage of cell division.
• Response depends on size/age of tumor and rate of replication.
• Concurrent agents can be used and classified by action.
• The route of administration is IV, oral, intracavitary, intrathecal.
• Central catheter administration via implanted port.
• Extravasation and vesicant drugs can damage tissue.

Chemotherapy Administration

• Involves safe preparation, administration, and disposal of cytotoxic medications.
• Requires chemo precautions and awareness of facility policy.
• Special certifications for nurses may be required.

Chemotherapy Side Effects

• Nausea and vomiting
• Anorexia.
• Diarrhea/constipatation
• Alopecia.
• Immunosuppression is significant adverse effect
• Loss of weight.
• Neurological symptoms.
• Impact on reproductive organs.
• Bone Marrow Suppression
• Thrombocytopenia.
• Anemia
• Stomatitis
• Fatigue
• Teach the patient how to cope with these effects

Cancer Treatment

• Provide emotional support.
• Medicate for pain and nausea.
• Allow for verbalization of concerns/fears.
• Promote nutrition.
• Maintain fluid balance.

Radiation Therapy

• Application of high-energy x-rays or particles to damage or kill cancer cells.
• Shrinkage of tumor.
• Localized treatment can be internal(brachytherapy), external or systemic
• Approximate 50% of patients will receive radiation.

Radiation Therapy: External (EBRT)

• Treatment Plan & Tumor lethal dose
• Nursing Management:
  • Treat side effects
• Skin Care:
  • Avoid sun
  • No deodorant or fragrances on area.
  • Wear loose clothing and protect the area.

Radiation Therapy: Internal(brachytherapy)

• Sealed source.
• Intra-cavity
• Nursing management.
• Time, distance, shielding are important
• Proper disposal of body fluids.

Nursing Actions

• Monitor patient for side effects and provide supportive care.
• Address potential issues of skin damage and fatigue.
• Measures to maintain tissue/skin integrity,
• Promote nutrition.
• Measures to prevent infection.

Immunotherapy/Biological Response Modifiers/Targeted Therapy

• Immunotherapy/biological response modifiers enhance the patient's own immune response and also have a direct anti-tumor effect.
• Targeted therapy targets specific genes/proteins to stop the growth of cancer cells, preventing tumors from forming new blood vessels.