14.6 Treatment options Flashcards
When is cancer treatment most effective?
When the cancer is detected early and is localised
What are the different treatment options for patients with cancer?
Surgery Radiotherapy Chemotherapy Hormonal therapies Targeted biological therapies
What does the choice of treatment depend on?
Cancer type
Stage and grade
Patient’s performance status, a measure which indicates their general health and ability to withstand aggressive treatments
Risk/benefit evaluation of the therapies
Patient’s personal choice
National guidelines for treatment of specific cancers
How are the majority of cancer cases treated?
About 2/3rds of cancer cases can be treated by surgery and/or radiotherapy, sometimes with a course of chemotherapy or hormonal therapy to make sure all malignant cells killed
Who is chemotherapy more suitable for?
Patients who had advanced disease at diagnosis
What are some of the reasons surgical techniques are used to treat cancer?
- To diagnose
- To cure
- Reconstructive
- Control symptoms and extend life
- To assist with other treatments e.g. central line insertion
Which cancers is surgical intervention likely to cure?
Small, early-stage that have not yet spread to other parts of the body
What is radiotherapy?
Use of radiation to destroy cancer cells in the area that is being treated
What is external radiotherapy?
Aims high-energy X-rays at the affected area using an external beam radiotherapy (EBRT) machine
What is conformal radiotherapy?
Computerised control mechanism in EBRT machine. Permits radiation beam to be programmed to give max dose to tumour and minimum to surrounding healthy tissue, reducing damage and side effects
What is internal radiotherapy?
Radioactive material placed inside the body. Radiation can therefore be place inside a tumour, so external damage is limited
What is chemotherapy?
Traditional chemotherapy uses cytotoxic drugs to destroy cancer cells
How does cytotoxic chemotherapy work?
Acts by stopping cell division. Kills dividing cells either by binding in some way to DNA, preventing the manufacture of raw materials of which DNA is made, or prevent cells from separating from each other
What are alkylating agents?
Bind and damage DNA, thus interfering with cell replication. Primarily damage rapidly dividing cells, particularly cells in bone marrow and GI tract. Often used to treat cancers of bone marrow e.g. leukaemias, lymphomas and myeloma
What are some examples of alkylating agents?
Cyclophosphamide Chlorambucil Melphalan Busulfan Lomustine Bendamustine Carboplatin Cisplatin
What are cytotoxic antibiotics?
‘Stick’ to DNA causing it to become tangled and preventing the cell from dividing. Work by preventing cell division or blocking enzymes involved in DNA replication.
What is the action of doxorubicin?
Binds to DNA preventing DNA and RNA synthesis.
Inhibits action of topoisomerase II enzyme that allows DNA to be reproduced.
What are some examples of cytotoxic antibiotics?
Doxorubicin
Bleomycin
Mitomycin
Dactinomycin
What are antimetabolites?
Prevent cell division by interfering with DNA and RNA synthesis. Can either substitute for the normal building blocks of RNA and DNA (purines and pyrimidines), or inhibit enzymes needed for DNA/RNA production
What is an example of an antimetabolite?
Methotrexate
What are vinca alkaloids?
Halt cell division and cause cell death by inhibiting the formation of a protein called tubulin required for microtubule formation, which is essential for mitosis
What are some examples of vinca alkaloids?
Vinblastine
Vincristine
Vinorelbine
Vindesine
What are taxanes?
Disrupt microtubule function by stabilising tubulin in the microtubule, thus inhibiting mitosis
What are some examples of taxanes?
Paclitaxel
Docetaxel
What are topoisomerase 1 inhibitors?
Inhibit the enzymatic activity of topoisomerase 1, which is involved in DNA replication
What are some examples of topoisomerase 1 inhibitors?
Irinotecan
Topotecan
What is hormone therapy and what tumours are they useful for?
Medicines that can block effect of hormones. Therefore only useful for tumours whose growth is stimulated by male or female sex hormones
How do hormone therapies act?
Blocking either the binding sites of these hormones or the production of the hormones by the body
Which hormones is breast cancer dependent on?
Oestrogen, progesterone or both
Which hormone therapies are used to treat breast cancer?
Tamoxifen
Aromatase inhibitors
LH blockers
Which hormone is prostate cancer dependent on?
Testosterone
Which hormone therapies are used for prostate cancer?
LH blockers
Anti-androgens
Gonadotrophin releasing hormone (GnRH) blocker
Novel hormone therapies e.g. abiraterone and enzalutamide
What is anastrozole used for?
Oestrogen-receptor-positive early invasive breast cancer
What is exemestane used for?
Oestrogen-receptor-positive early breast cancer
What is fulvestrant used for?
Oestrogen-receptor-positive advanced breast cancer
What is tamoxifen used for?
Advanced oestrogen receptor positive breast cancer, anovulatory infertility
What is abiraterone used for?
Advanced prostate cancer
What is enzalutamide used for?
Advanced prostate cancer
What are targeted therapies?
Act on processes in cells. May be used to control growth of cancer cells, stimulate the immune system to attack cancer cells, or specifically identify cancer cells and destroy them
What do targeted therapies target?
Specific genes or proteins that make a cancer cell different to a normal cell. Therefore majority of these medicines rely on the knowledge of the abnormal gene or protein
What are the different types of targeted therapies?
Monoclonal antibodies
Cancer growth inhibitors
Immunotherapy (interferon and interleukin 2, cancer vaccines)
What are monoclonal antibodies?
Modified antibodies so that they will attach to artificial targets, including cancer cells. They attach to specific proteins on the surface of cancer cells
How may monoclonal antibodies destroy cancer cells?
- Triggering the immune system to attack and kill cancer cells
- Carrying cancer drugs or a radioactive substance directly to the cancer cells (radio-immunotherapy)
- Blocking signals that tell cancer cells to divide
What do all monoclonal antibodies have at the end of their generic name?
‘mab’
What are targeted small molecular inhibitors?
Block the growth and spread of cancer by interfering with specific proteins (growth factors) that trigger cells to grow and divide or stimulate tumour blood vessel development
How may cancer growth inhibitors stop the progression of disease?
- Reducing the levels of a growth factor in the body
- Blocking the growth factor receptor on the cancer cell
- Blocking the signals in the cells triggered by the growth factor and receptor
What do all small molecule inhibitors have at the end of their generic name?
‘nib’
What is the target of alemtuzumab?
CD52 protein on surface of mature B-lymphocytes (immature B cells do not express CD52 so are able to replenish the B cell population after treatment)
What is alemtuzumab used to treat?
Chronic lymphocytic leukaemia
What is the target of bevacizumab?
Tumours expressing vascular endothelial growth factor (VEGF)
What is bevacizumab used to treat?
Advanced bowel cancer Advanced non-small cell lung cancer Advanced kidney cancer Advanced ovarian cancer Fallopian tube cancer Peritoneal cancer Advanced breast cancer Advanced cervical cancer
What is the target of cetuximab?
Tumours that express epidermal growth factor receptor (EGFR)
What is cetuximab used to treat?
Advanced bowel cancer
Head and neck cancer
What is the target of trastuzumab?
Tumours that express human epidermal growth factor receptor 2 (HER2)
What is trastuzumab used to treat?
Early or advanced breast cancer
Advanced stomach cancer
What is the target of vemurafenib?
Tumours with the mutation in BRAF gene
What is vemurafenib used to treat?
Advanced melanoma positive for BRAF mutation
What is the target of dasatinib?
Inhibits multiple tyrosine kinases
What is dasatinib used to treat?
Chronic myeloid leukaemia
Acute myeloid leukaemia positive for Philadelphia chromosome
Acute lymphoblastic leukaemia positive for Philadelphia chromosome
What is the target of imatinib?
Inhibits multiple tyrosine kinases
What is imatinib used to treat?
Chronic myeloid leukaemia
Gastro-intestinal stromal tumour
Acute lymphoblastic leukaemia positive for Philadelphia chromosome
What is the target of erlotinib?
Tumours that express epidermal growth factor receptor (EGFR)
What is erlotinib used to treat?
Advanced pancreatic cancer
Advanced non-small lung cell cancer
What is the target of lapatinib?
Tumours that express human epidermal growth factor receptor 2 (HER2)
What is lapatinib used to treat?
Advanced breast cancer
What is immunotherapy?
Uses components of body’s immune system to attack and destroy cancer cells
How cytokines engineered for immunotherapy?
Isolate the genes that control their production, then transfer them to bacteria and use the bacteria for cytokine production by growing them in fermenters. The cytokines act by stimulating parts of the natural immune system to attack cancer cells
What is radio-immunotherapy?
Antibodies that can recognise and bind to cancer cells. Can be coupled chemically with a radioactive material such as iodine-131 and used for scanning for tumours or treatment
What are immuno-modulators?
Generated using patient’s own cells which are harvested and stimulated to respond to the tumour
How is chemotherapy delivered?
As it is a systemic treatment, it must get into bloodstream
What are the mechanisms of chemotherapy delivery?
Intravenous Oral Lumbar puncture Intramuscular Cream rubbed into skin Injection into chest cavity Injection into tumour
What are common side effects of cytotoxic chemotherapy?
Anaemia Neutropenia (low no. WBCs) Mucositis (inflammation of and ulceration of lining of digestive tract) Alopecia Tiredness Constipation Nausea and vomiting Diarrhoea Serious infection
What is remission?
No evidence of cancer following treatment. May last for several years or cancer may never return
How do surgeons prevent localised regrowth of tumours?
Take a margin of healthy tissue around a tumour for pathological examination
What are common reasons for return of a tumour?
Medicine may not be powerful enough to eliminate tumour entirely, so when it is stopped cancer cells start to grow again.
Resistance to medicine used
What has been designed to prevent cervical cancer?
HPV vaccine
Does the HPV vaccine protect against all strains of HPV?
No, therefore patients should continue with routine cervical screening
Which cancers have vaccines in clinical trials?
Non-small cell lung cancer Lung cancer Pancreatic cancer Prostate cancer Bowel cancer
