Cancer therapy

• Cancer therapy includes

  • surgery
  • chemotherapy
  • radiation therapy
  • biological and targeted therapy
  • bone marrow and stem cell transplantation
• Care with cure goal

  • treatment that has the more likelihood of eradicating the disease
  • can induce permanent remission
  • example: surgical removal of skin carcinoma
• Care with control goal:

  • treatment plan for cancers that cannot be completely eradicated but are responsive to cancer therapies
  • no cure but can be controlled for extended period of time, similar to a chronic illness
  • example: chronic lymphotic leukemia
• Care with palliation goal:

  • relief or control of symptoms
  • optimize quality of life is primary goal
  • example: radiotherapy to relieve pain of bone metastasis
• Surgical therapy is the removal of the tumor and a margin of the surrounding normal tissue may cure localized cancer but is ineffective if cancer has metastasized
• Surgical therapy for cure and control goal:

  • cancer with slow rate of cellular proliferation
  • adjuvant therapy used to eliminate residual micrometastases
  • includes lumpectomy, mastectomy, bowel resection, pneumonectomy, thyroidectomy
• Surgical therapy for supportive and palliative care

  • offer supportive care and palliate symptoms
  • feeding tube in stomach for esophagus cancer
  • suprapubic cystomy in advanced prostate cancer
  • debulking tumor to relieve pain
• Surgical therapy for rehabilitive care: follow curative or radical surgery to reestablish function or rebuild for better cosmetic effect (eg: breast reconstruction after mastectomy)
• Chemotherapy goal is to reduce the number of cancer cells present in the primary and metastatic tumor sitesby inhibiting their growth and reproduction
• Chemotherapy influencing factors

  • mitotic rate
  • tumor size and age
  • location
  • presence of resistant tumor cells
• Effects of chemotherapy

  • cannot selectively distinguish between normal and cancerous cells
  • adverse and toxic effects result from destructions of normal cells
  • most affected tissues are fast growing tissues including bone marrow, GI lining, integumentary
• Administration of chemotherapy is done by trained and certified nurses. It is an extreme care for correct dosage, need to double check with physician orders and pharmacist preparation
• Radiation therapy is used when the tumor is located in one area. It consists of killing the cancerous cells through radiation
• Radiation therapy

  • emission and distribution of energy
  • absorbed into tissue producing ionization
  • results in generating free radicals breaking the chemical bonds in DNA
  • causes lethal damage to cell = cannot replicate - cell death
• Biological and targeted therapy consists of biological agents like interferons, interleukins, monoclonal antibodies and growth factors that reshape the dynamic between the host and tumor which impedes tumor growth
• Biological and radiological therapy enhances, restores or regulates the natural immune system mechanisms
• Biological therapy

  • interferon: inhibit tumour growth and increase recognition by immune system
  • monoclonal antibody: attack cancer cells and increase immune response
  • interleukins: activates immune system and alters tumour cell function
  • hematopoietic growth factors: speed up bone marrow recovery, stimulate growth of RBC
• Bone marrow and stem cell transplantation

  • patients with resistant or unresponsive tumor to chemotherapy and radiotherapy
  • goal is to cure, not for palliative care
  • procedure with many risks, highly toxic
• Stem cell transplants

  • autologous stem cell transplant: from yourself to yourself, enable pt to receive intensive chemo
  • allogenic stem cell transplant: from someone else to yourself, rescue bone marrow so subsequent proliferation is normal
• How do we decide goals

  • goals of care
  • patient’s goal (bucket list)
  • global picture
  • quality of life is more important than quantity of life