Therapeutic Options Flashcards
1
Q
Prevention methods
A
- Diet
- Stop people smoking
- Screening
- Genetics
- Medication
2
Q
Diet in prevention
A
- Inconsistent evidence, lots of confounding factors
- CRC is probably linked with red meat consumption
- Breast cancer: probably a link with saturated fat intake
- Physical activity decreases risk
- Current advice: 5 or more portions of fruits and vegetables a day, avoid obesity, take regular exercise 30 minutes a day
3
Q
Screening in prevention
A
- Risks are involved with screening, so you may cause harm
- E.g. breast screening might perform a mammectomy on a patient who has a lump that may never turn into cancer
- High quality evidence for smear tests, CRC (faecal occult blood test), breast cancer
- Controversial: PSA blood test for prostate cancer, MR/CR or breath test for lung cancer
4
Q
Genetics in prevention
A
- CRC and familial adenomatous polyposis coli (FAP)
- Autosomal dominant
- Screening families for APC mutations
- Regular colonoscopy
- Offer panprotocolectomy when adenomas found
- Breast cancer: BRCA1, BRCA2
5
Q
Medication in prevention
A
- Also known as chemo-prevention
- More controversial
6
Q
Primary medication in prevention
A
- Oesophageal cancer: high rate in parts of chine, they tried anti-oxidant supplements but there was no benefit
- Breast cancer: at risk women, prophylactic tamoxifen (higher risk of getting endometrial cancer with this)
7
Q
Secondary medication in prevention
A
- Previous head and neck or lung cancers
- Give anti-oxidant supplements
- No benefit
8
Q
Treatment
A
- Local or regional treatment: surgery or radiotherapy
- Systematic therapy: hormonal, chemo, immunotherapy
9
Q
Surgery treatment of cancers
A
- Need anatomical clearance
- Get all the cancer out
- 50% of cancers cured this way
10
Q
Radiotherapy treatment of cancers
A
- Needs anatomical coverage
- Can treat inoperable lesions
- Can treat things you can’t remove and/or allow surgery to be possible
- Approx. 40% of cancers cured by this
- Can be combined with chemo: anal cancer, rectal cancer, oesophageal cancer
- Palliation
- Maintain function and/or appearance
11
Q
Palliation
A
- Reduce pain
- Bleeding
- Swollen limbs
- Aims to improve symptoms
12
Q
Maintaining function with radiotherapy
A
- Gullet cancer, you can’t remove it so you need to maintain function
- Ear lesion, you can keep your ear with radiation therapy
13
Q
5R’s of radiobiology
A
- Radiosensitivity
- Repair
- Re-population
- Re-oxygenation
- Re-assortment
14
Q
Radiosensitivity
A
- How sensitive the tumour is going to be to treatment
- Can anticipate outcome
- Certain drugs have been proven to increase radiosensitivity
15
Q
Repair
A
- Radiation damages cells to a sublethal level, often the cell pathways repair themselves have been suppressed in malignant tumours
- The degree of suppression will affect the repair half-life and how effective the treatment is
16
Q
Re-population
A
- Cells will all be in different parts of the cell cycle
- S phase: typically radioresistant
- Late in G2 or M phase are relatively sensitive
- Idea is you catch them at some point in the cycle when they’re in a more sensitive phase
17
Q
Re-oxygenation
A
- Tumours can be acutely or chronically hypoxic, this makes the resistant to radiation
- The aim of radiation is to make them oxic as oxic cells can be killed
18
Q
Re-assortment
A
- Cells are in a cycle and you catch some cells at different stages, some are sensitive to radiotherapy and some aren’t
- G2 and M are good, late S isn’t so good
19
Q
Systemic therapy
A
- Beneficial for widespread disease
- Can result in widespread toxicity
- Palliation in about 50% of cancers
- Potential to be very specific
- Therapeutic index: aim is to have the anti-tumour effect curve and normal tissue toxicity as far apart as possible. Separates side effects and anti-tumour effects
20
Q
Hormonal therapy
A
- ‘Specific’ or ‘targeted’ therapy
- Benefits in breast cancer (oestrogen receptor positive and tamoxifen) and prostate cancer (luteinising hormone-releasing hormone antagonists)
- Trials in prevention for high risk groups e.g. tamoxifen
21
Q
What are the 4 basic types of chemotherapy?
A
- Curative
- Palliative
- Adjuvant
- Neoadjuvant
22
Q
Curative chemotherapy
A
- Only about 3% of cancers, testicular, lymphomas
- Can be used with radiotherapy
- Important to use biomarkers to see what genes the tumours have, assess treatment methods
23
Q
Palliative therapy
A
- Accounts for around 50% of chemotherapy
- Aim is to relieve symptoms
24
Q
Adjuvant
A
- When there is no longer evidence of pathology
- Can reduce risk of recurrence. Based on population statistics rather than the individual
25
Q
Neoadjuvant
A
- Aim is to improve survival and reduce morbidity
- Precedes surgery or radiotherapy
- Before people have surgery to see how the cancer is going to behave and decide whether to do local or systematic therapy
- Can be used to assist the surgery by ensuring cancer cells are removed in the operation and not in the bloodstream
26
Q
Immunotherapy
A
- Specific and non-specific types
- Antibodies can target cancer, you can have a combination of mouse and human antibodies… one half of the antibody could be targeting one part and the other half of the head could be targeting another
27
Q
Types of immunotherapy
A
- Monoclonal antibodies
- Programmed cell death pathway (PD-1)
- Chimeric antigen receptor (CAR) T-cells
28
Q
Programmed cell death pathway (PD-1)
A
- Uses immune system to attack ‘foreign’ cancer cells
- Cancer hides behind inhibitors, this drug allows the immune system to see the drug
- It can make things worse if you have co-morbidities
- being used in lung cancer and melanoma
29
Q
Chimeric antigen receptor (CAR) T-cells
A
- Artificial T-cell receptors, using retroviral vectors to give a specific cell killing function directed against cancer cells
- Very new
- In lymphomas and leukaemias, not solid cancers
- Side effects: you’re taking lymphocytes out of circulation
- You put them back via T cell adoptive transfer
30
Q
CAR T-Cells monitoring
A
- Disease response: CT scans, bone marrow biopsies, peripheral blood flow cytometry
- CAR T-Cell persistence: Immunohistochemistry of bone marrow biopsy, RT-PCR and flow cytometry of blood and bone marrow aspirate
31
Q
Designer therapies
A
- Specific, based on molecular science
- You look at intracellular growth points
- EGFR inhibitor - in lung cancer need to have a specific mutaiton
