Systemic Anti Cancer Therapy Flashcards
Describe the types of drugs used in cancer treatment.
- CYTOTOXIC - target DNA structure/segregation during mitosis
- TARGETED AGENTS - interact with specific molecular targets
- HORMONAL - involved in biochemical pathways related to hormone function
- BIOLOGICAL - macromolecules with specific target/can regulate immune response to kill tumor cells
Describe the principles of chemotherapy.
- Cytotoxic agent administered
- Kills differentially - normal cell recovers whilst cancer cells die
What are the aims of anti-cancer therapy?
- CURATIVE - preventative, treatment before surgery, concurrent treatment
- PALLIATIVE
What patient factors are taken into account during anti-cancer therapy?
- Age
- Organ Function
- Co-morbidity
- Past medical history
- Toxicity response
What significant process do cytotoxic cells disturb in cancer cells?
The cell cycle
Describe anti-tumour antibiotics.
- Interefere with DNA function
- Several other mechanisms can occur e.g cell membrane alteration, topoisomerase inhibition
- EXAMPLES - Bleomycin, doxorubicin
Describe alkylating drugs.
- Form methyl cross bridges between 2 strands of DNA base pairs
- Prevents DNA separation in cell division
- EXAMPLE: Cyclosphamide, platinum agents, dacarbazine
Describe antimetabolites.
- Interfere with cell’s ability to utilise cellular metabolites
- Toxic effects induced
- EXAMPLES - methotrexate, 5FU, cytarabine
What are some examples of plant derived cytotoxic drugs?
- VINCA-ALKALOIDS inhibit mitotic spindle formation by binding to bulin e.g Vincristine and Vinblastine
- EPIDOPHYLLOTOXINS interfere with topoisomerase II e.g etoposide
- TAXANES - inhibit mitosis by causing disorganised microtubule assembly
What are the principles behind combination therapy?
- Avoid drugs with overlapping toxicities
- Administer drugs at optimal dose and schedule - determined in clinical trials
- Chemotherapy given at regular intervals - minimise time between cycles
What are three ways chemotherapy is administered?
- Oral
- IV
- Intrathecal
Give an example of a combination therapy for a small cell cancer.
- ETOPOSIDE + CARBOPLATIN/CYSPLATIN
- 4-6 cycles
- 3 weekly
Give an example of a combination therapy given in non small cell cancers.
- Single agent carboplatin/cisplatin
- Added to non-platinum agents like Pemetrexed
What types of healthy cells are most negatively affected by chemotherapy drugs?
- Rapidly dividing cells
- EXAMPLE - cells in skin, bone marrow, GI tract and hair follicles
What are some late side effects of chemotherapy?
- Heart, lung and liver damage
- Fatigue
- Infertility
- Neurological effects
What principle is hormone therapy based on?
- Cancers can be hormone sensitive - require specific hormones to grow/develop
- Hormone therapies reduce ability of organs to produce these hormones
Outline some possible mechanisms of action of biological therapies.
- Act on cellular processes
- Stop cancer cell growth and division
- Encourage immune system to attack cancer cells
- Direct killing of cancer cells
Outline some types of biological therapies
- Monoclonal antibodies
- Immunotherapy
- Cancer growth blockers
- Anti-angiogenics
Describe monoclonal antibodies
- Attach to cell surface antigen
- Block signal from surface antigen that would otherwise lead to cell growth and replication
Describe anti-angiogenics.
- Blocks VEGF - stops growth of blood vessels
- Starves cancer of oxygen and nutrients
- Act on chemicals that cells use to signal each other to grow e.g thalidomide
Describe cnacer growth blockers.
- Oral medications
- Block intracellular pathways leading to replication
- Continous treatment until disease progession
- EXAMPLE - Tyrosine kinase inhibitors
Describe immunotherapy.
- Stimulate innate immunity and remove check points of immune suppression
- Slows growth and stops spreading
- Done through T cell therapy and monoclonal antibodies
Describe checkpoint inhibitors in immunotherapy.
- Cancer suppresses immune response through direct binding to immune cells - undermines clinical efficacy of cancer therapy
- Inhibitors target these methods of immune evasion
- Unblock suppressed immune response - T cells mobilised causing death of cancer cells
What are the side effects of immunotherapy?
- Pneumonitis
- Colitis
- Hepatitis
- Pancreatitis
- Endocrine disorders
Describe vaccines in anti-cancer therapy.
- Trigger immune system
- Used to prevent precursors to cancer e.g BCG/HPV vaccine
- Direct treatment vaccines in development
On a patient level, what should be considered in cancer care?
- See and know the patient - holistic care
- Empower patients
- Concept of ‘no decision about me - without me’
- Be mindful of rollercoaster of emotions that come with tough decisions stemming from cancer diagnosis and treatment
