(SYNOPTIC) Cancer Recap Flashcards
What does the ‘pathobiology’ of cancer refer to?
How a cancer cell forms
What is cancer?
Collection of diseases
Underlying features of uncontrolled cell growth
How is a cancer cell formed?
Normal cell undergoes specific changes
Allows it to proliferate without normal limit
Spread to surrounding/ distant tissues
What are the hallmarks of a cancer cell?
(1) Growth factor independence
(2) Insensitivity to growth inhibitors
(3) Proliferation without limit
(4) Avoid apoptosis
(5) Promote angiogenesis
- Development of new blood vessels
(6) Invade and metastasise
What causes cancer?
A single cell acquiring most/ all hallmarks of cancer via multiple mutations
Why is cancer more prevalent in older people?
Developing enough mutations to progress to a cancerous cell takes time
As it requires multiple mutations to achieve most/ all hallmarks
What are the aims in management of cancer?
(1) Prevention
(2) Early detection
(3) Total eradication
What is the hierarchy of aims in cancer management?
(1) Cure
- Eradication of tumour + metastasis
(2) Remission/ mitigation
- Significant reduction in tumour load
(3) Symptomatic care/ palliation
- Treatment of secondary complications
- Relief of symptoms
(4) Terminal care
- Improve quality of life
- Optimise symptom control
What are the main modes of therapy in cancer?
(1) Surgery
(2) Chemotherapy
(3) Radiotherapy
When is surgery appropriate in cancer therapy?
(1) Well-defined solid tumour
(2) Non-vital region
(3) Non-mutilating result
(4) Resection/ reconstruction possible (e.g. gut)
When is chemotherapy appropriate in cancer therapy?
(1) Adjuvant therapy following surgery/ radiotherapy
(2) Neo-adjuvant therapy prior to surgery/ radiotherapy
(3) Widely disseminated/ metastasised
(4) Diffuse tumour
(5) Palliation
- Reduce symptoms
(6) Some primary tumours
- e.g. Hodgkins lymphoma
When is radiotherapy appropriate in cancer therapy?
(1) Diffuse but localised tumour
(2) Vital organ/ region
- Head/ neck/ CNS
(3) Adjuvant therapy
(4) Palliation
What is the rationale of chemotherapy?
Target cancerous cells during rapid proliferation
What is important when choosing chemotherapeutic agents for use in combination?
Minimal overlap in toxicity
Why should chemotherapy be delivered intermittently?
To allow for recovery of most sensitive tissues
- Rapidly dividing, e.g. bone marrow/ gut mucosa/ hair follicles
What are some rapidly dividing cells in the body?
(1) White blood cells (bone marrow)
(2) Gut mucosa
(3) Hair follicles
How do anti-metabolites function in chemotherapy?
G1 Phase
- Prevent synthesis of components of DNA
How do microtubule inhibitors function in chemotherapy?
G2 Phase
- Prevent cells making components needed to separate
What are some examples of anti-metabolites?
(1) Methotrexate
(2) Azathioprine
What are some examples of microtubule inhibitors?
Vinca alkaloids
- Vinblastine
- Vincristine
- Docetaxol
How do agents binding to DNA function in chemotherapy?
S Phase
- Prevent DNA synthesis
What are some examples of agents that bind to DNA in chemotherapy?
(1) Alkylating agents
(2) Anti-tumour ABx
(3) Platinum compounds
When were single chemotherapy agents used?
Used until early 1960s
When was combination chemotherapy introduced?
1960s
Why is combined chemotherapy used, instead of single chemotherapy?
(1) Increased remission
- More patients
- Longer remission period
What is a downside of combined chemotherapy?
Increased side effects
What are some potential single agent chemotherapies still used?
(1) Tyrosine kinase inhibitor
(2) Monoclonal Antibodies
How can side effects of chemotherapy be minimised?
(1) Close monitoring
- FBCs
(2) Cycle
- Allow for marrow recovery between treatments
- Administration of stem cells to selectively enhance bone marrow proliferation
(3) Forced diuresis
- Given with nephrotoxic/ bladder-toxic drugs
- Reduce contact time + urine conc.
What is forced diuresis, used in chemotherapy?
Modest over-hydration before therapy
Followed by a diuretic
Why is forced diuresis used in chemotherapy?
Maintain a high urine output for at least 24hrs following therapy
Reduce urine conc. + contact time of nephro/bladder-toxic drugs
What is an example of a drug used in forced diuresis?
Mannitol
