Cancer treatment Flashcards
What is the ideal form of cancer treatment?
One that removes all cancer cells without killing healthy cells
What would be a typical treatment for a localised cancer?
Surgical removal & chemotherapy/radiotherapy to kill off residual cancer
What is the basic principle behind cancer treatment?
Kill cancer cells & prevent further growth of tumour
Why is surgery the optimum treatment?
Maximum efficiency on cancer cells minimum efficiency on healthy cells
What solutions cannot be treated by surgery?
Leukaemia & solid cancers metastised to inaccessible are of bone & brain
What is a cytostatic effect?
Prevent cell proliferation - stop growth but not eliminate it
What is a cytotoxic effect?
Killing of cancer cells - can cure patients
Is chemotherapy specific or broad spectrum?
Broad spectrum
What processes do chemotherapy affect?
DNA synthesis & cell proliferation
How do specific chemotherapy drugs target cells?
Based off differentiation properties - treat prostate & breast cancer
Is hormone therapy specific?
Yes affects hormone controlled cancer e.g. breast, ovarian, penal, prostate
What affect does x-rays have on cells?
DNA is irreversibly damaged by ionising radiation - radiotherapy
How can cytotoxic drugs be targeted to specific cells?
Can be attached to antibodies that target proteins on cancer cells
What benefit do angiogenic drugs have?
Prevent metastatic growth - metastasis involves processes such as angiogenesis - these drugs prevent this process
What is prognosis?
Likely future behavior & outcome for patient
What are prognostic factors?
Tumour size, tumour spread, specific biochemical markers, tumour markers in tissue/blood
What is remission?
Decline in cancer size as a result of treatment
What is relapse?
Reappearance of a cancer
What can reduce cancer deaths?
~Screening programmes - cervical, breast, colon
~Vaccination - HPV for cervical cancer
What is complete response to cancer treatment?
When a cancer disappears completely
What is partial response to cancer treatment?
Partially removed / some remains
What is no change as a result of cancer treatment?
Remains static
What is progressive disease in terms of cancer treatment?
Continues to grow
What is the difference between the stage and grade of a cancer?
Stage - tumour size & degree of spread
Grade - cellular characteristics
How is staging of cancers done?
TNM system
1.Tumour size
2. Spread to lymph nodes
3. Metastasis to distant sites
4 stages
How is grading determined?
Low grade - histological resemblance to tissue of origin
High grade - only marginally resembles tissue
Based off mitotic rate & irregularities in nuclear shape , and if cellular architecture resembles tissue of origin
Does early detection affect treatment prognosis?
Cancer detected - developing for long time -1cm tumour - 3 /4 of its lifespan
Increased time = increased cellular change - earlier = better response to treatment
How does surgery work for cancer treatment?
Surgical removal - some remain - debulking makes drug & ionising radiation treatment more successful -
What is radiotherapy?
X-rays damage DNA & kill cancer cells - differ in sensitivity e.g. radiation that kills thyroid cells 4x more than kills bone cells - finely focused and given over several weeks to avoid death of healthy cells
What is chemotherapy?
Drugs that block proliferation - most effective against rapidly dividing cells - conc. of drugs & duration of exposure resulting in effectiveness - side effects on healthy tissue minimised by using combinations of drugs and varying toxicities - mutagens - 10x risk of developing leukaemia
What is primary chemotherapy?
First line of treatment for local disease
What is adjuvant chemotherapy?
Used in addition with surgery - post mastectomy for breast cancer
What are 3 types of chemotherapeutic drugs?
Alkylating, antimetabolites, & natural products
What are alkylating agents & give an example?
Alkylate DNA - transfer alkyl group from one molecule to another - cyclophosphamide affects DNA synthesis treat breast, leukaemia
What are antimetabolities and give an example?
They antagonise metabolites needed for DNA synthesis - methotrexate affects dihydrofolate reductase treat breast, placenta
What are natural product chemotherapeutic drugs?
From plant & fungi - doxorubicin affects DNA & RNA synthesis affect lung, breast, & leukaemia
What are the side affects of chemotherapy?
~Haemopoietic cells affected - anaemia, thrombocytopenia, neutropenia
~Destruction of immune cells
~Loss of hair follicles (rapidly dividing)
~Nausea & vomiting - (use anti-emetic drugs to treat)
What is hormone therapy?
Medicines to block or lower the amount of certain hormones - stop/slow down cancer - (prostate & breast require steroid hormone for growth) - responsive cells contain specific receptors for hormones, unaffected by hormone antagonist - prevents excess steroid synthesis blocking affect of target cell via receptor machinery - tamoxifen in breast cancer & anti-androgens in prostate cancer
What is immunotherapy?
Use or manipulate immune system to facilitate attack & lyse tumour cells
What are tyrosine kinase inhibitors?
Interfere with enzymes & proteins involved in cell signaling pathways controlling cell proliferation
What are monoclonal antibodies?
e.g. Herceptin - targets Her 2 proteins/receptors on cancer cells - interferes with cell signaling pathway & slow cell proliferation
What is gene therapy?
Gene inserted - down regulate growth promoting product
What is CAR-T cell therapy?
Combination of cell therapy, gene therapy, immunotherapy - T cells genetically manipulated - target antigens on cancer cells
