Cancer

Risk factors, genetics, pharmacy, treatments, studies, policy

Primary prevention in cancer aims to:

Prevent cancer from occuring

Name three preventable cancers

Lung, tongue, bowel

What does ‘incidence’ mean?

New cases per year

What percentage of cancers are inherited?

5%

BRCA1 and BRCA2 mutations increase the risk of which cancers?

Breast, ovarian and cervical

Give an example of secondary prevention in cancer.

Cancer screening for early detection

Give two limitations of screening.

False positive and false negatives

Which cancer does the HPV vaccine prevent?

Cervical cancer

What is commonly experienced after cancer treatment ends?

A “cliff edge” feeling

What two other aspects are included in a holistic needs assessment other than health?

Financial and social needs

What is a ‘social death’?

Loss of identity and social roles

What is tumorigenesis?

The formation of tumours

What gives cancer its cell growth advantage?

Multiple mutations

What does "clonal expansion” mean?

Mutated cells replicate and pass on changes

Describes epigenetics.

Gene expression changes without altering the DNA sequence

What does global hypomethylation lead to?

The over expression of certain genes and increased mutations

What does hypermethylation lead to?

An under expression in genes so they become silenced

What percentage of tumour cells are cancer stem cells?

0.1-0.8%

Name two aspects of cancer stem cells

Drug-resistant and self-renewing

How do DNMT inhibitors work?

By reactivating silenced genes

How do HDAC inhibitors work?

By reversing gene repression

What makes epigenetic cancer therapies useful?

Epigenetic changes are reversible

What is a downfall in conventional chemotherapy?

It cannot kill cancer stem cells effectively

What is a good therapy strategy to prevent relapse?

Target cancer stem cells

Why are cancer cells more sensitive to epigenetic therapy?

They cannot tolerate epigenetic disruption

What does ‘bioavailability’ mean?

The percentage of a drug that reaches systemic circulation unchanged

Which drug administration route has 100% bioavailability

IV - intravenous

Where does first-pass metabolism occur?

In the liver

What does ‘pharmacokinetics’ mean?

The action the body takes on the drug

What does a ‘high volume of distribution’ mean?

A drug is widely distributed around the tissues rather than staying in the plasma

If a drug is highly lipid soluble, what ‘volume of distribution ‘does it have?

High Vd

Give an example of a prodrug

Codeine

Where are most drugs excreted?

The kidneys

What is half-life?

The time for the concentration of a drug to halve

What does an agonist do?

Activates receptors

What does a competitive antagonist do?

It competes for the same binding site as the substance

Which cytochrome enzymes affect metabolism?

Cytochrome P450

What does pharmacogenetics explore?

How genetic variation influences drug response

Who is most at risk of adverse drug reactions?

The elderly

What do ‘QALYs’ measure?

Quality and quantity of life

What is the main aim of cancer surgery?

To remove localised tumours

What is the main mechanism of radiotherapy?

Using ionising radiation that causes DNA damage

What is brachytherapy?

Radiation that involves implants

What is external beam therapy?

Radiation that uses rays of gamma or electrons and requires fractionation

Give an example of a radioisotope.

Radioactive iodine

Give two positives for proton therapy

precise targeting and less damage to healthy tissue

What is hypoxia?

Where body tissues don’t have enough oxygen

How does hypoxia affect cancer treatment?

It reduces the treatment response

Which cells does cancer treatment primarily target?

Rapidly dividing cells

Which drug class damages DNA directly?

Alkylating agents

How does paclitaxel work?

By blocking the mitotic spindle

What is a major cause of chemotherapy resistance?

Cancer stem cells

Which pathway do checkpoint inhibitors target?

PD-1 and CTLA-4 pathways to restore T-cell activity

How do “hot tumours” respond to immunotherapy?

Well

What do PARP inhibitors affect?

DNA repair

What does progression-free survival mean?

time after treatment before more tumor growth

Name the four uses for chemotherapy

curative, palliative, neoadjuvant before surgery and adjuvant after surgery

What do antimetabolites do?

Block DNA synthesis

What do mitotic inhibitors do?

disrupt microtubules

What do topoisomerase inhibitors do?

prevent DNA repair

Name three types of immunotherapy

vaccines, cytokines and monoclonal antibodies

Which tumour type respond poorly to immunotherapy?

Cold tumours

What does ‘translational research’ mean?

Applying lab findings to clinical practice

What does a prognostic marker predict?

Disease outcomes

What are case-control study participants selected on?

disease status

Which study design is best for rare diseases? and why?

case-control because can identify risk factors

Which study helps to calculate relative risk?

Cohort studies

Which study cannot establish causality?

Cross-sectional studies

Which study does recall bias affect?

case-control studies

What do polygenic risk scores do?

Combine multiple single nucleotide polymorphisms

What is the improvement of drug effect due to belief?

The placebo effect

What does clinical equipoise mean?

Uncertainty about which is the best treatment

What is the main purpose of healthcare regulation?

To ensure safe and effective care

Name three things that health policy is influenced by

politics, economics and science

Who does NICE provide guidance for?

The NHS

What do NICE decisions consider?

cost and clinical effectiveness as well as patient input

What does ICER assess?

Cost-effectiveness

What does equality in healthcare mean?

The same care for everyone

What does equity in healthcare mean?

Care based on an individuals need

What is a key criticism of NICE?

Delays access to treatments

What is the difference between mortality and morbidity?

Mortality is death, morbidity is illness

What is a pre-conception prevention strategy?

Genetic testing

Name a pro and a con for genetic testing for cancer

Risk identification and cost or anxiety

How do you screen for bowel cancer?

FIT test

What vaccine prevents liver cancer?

Hepatitis B

What is an upstream public health approach?

Policy change

What is a downstream public health approach

Individual behaviour change

Name 4 points of uncertainty in the cancer journey.

diagnosis, treatment decisions, end of treatment, follow up

What is counselling an example of?

Supportive interventions

What was the impact of COVID-19 on cancer pathways?

less screening, delayed diagnosis and increased mental health issues

What is a good death?

location, support, symptom management

What do medical deaths focus on more than home deaths?

Treatment rather than experience

What model is a compassionate community part of?

The social model for care

What is global hypomethylation?

What causes early cancer development and genomic instability

What is the clinical use of epigenetics?

early diagnosis and prediction of treatment response

What does DNMT stand for?

DNA Methyltransferase Inhibitors

What do DNMTs do?

Epigenetic treatment that prevents normal hypermethylation

What does HDAC stand for?

Histone Deacytylase inhibitors

What do HDACs do?

epigenetic treatment that reverses transcriptional repression

Why is epigenetic therapy good?

Cancer cells are highly sensitive to epigenetic disruption but normal cells can adapt to changes