H7: Guest lecture cancer screening

health promotion

Encouragement of activities that facilitate healthy living and well-being

Disease prevention

Assessment of health risks and development of interventions that halt disease progression

Burden of disease of cancer

2nd leading cause of death worldwide

Europa high number but not many die (compared to other countries)

Mortality trends: general decrease across whole population

cancer-specific example of primary prevention

Tobacco cessation programs to prevent lung cancer

cancer-specific example of secondary prevention

Mammography screening for breast cancer

cancer-specific example of tertiary prevention

Pain management during cancer therapy

Screening

checking for disease in individuals who have no symptoms

Two major approaches of screening

opportunistic screening = test is offered during consultation for other reason

population screening = systematic, organized invitation of population (subset) (

Why screen for cancer? (4)

• High disease burden (urgency!)

• Availability of tests and treatment (is it ethical to screen if we don’t have treatment?)

• Possibility of detection before symptoms appear (pre-clinical stage)

• Improve health outcomes

What is the goal of cancer screening? (3)

Reduce cancer mortality

Reduce cancer incidence

  Improve survival and quality of life

Example: colorectal cancer screening

Takes 15 years = BIG WINDOW for detection and do something about it

Can keep growing and spread

Screening itself: All individuals aged 55-75 are invited every two years

- Receive a stool test by mail (fecal immunochemical test, FIT)

- Recognizable purple envelope

- Examination in the lab → results

If the stool test contains more blood than the cut-off value = positive test

→ a follow-up diagnostic test is needed: colonoscopy

Harms of screening?

Balance between benefits and harms!

- Physical

- Psychological

- Economical

→need to be considered for before implementation and continuously evaluated

example of screening harm: false positive stool test in colorectal cancer screening : potential harms on 3 lvls

• Physical: Unnecessary colonoscopy and bowel preparation, small risk of complications

• Psychological : Anxiety/distress due to positive test, altered self-perception

• Economical: Colonoscopy costs, wasted medical capacity, transportation, productivity loss

example of screening harm: false negative stool test in colorectal cancer screening : potential harms on 3 lvls

• Physical : Missed findings, worse survival outcomes and quality of life

• Psychological : Emotional burden, false reassurance, potential continuous engagement in risk factors

• Economical: High treatment costs in late cancer stages, productivity loss

Other potential harms and considerations of screening (5)

Overdiagnosis

• Diagnosing disease that would not negatively affect an individual during their lifetime

Equity

• Access to screening: socioeconomic, geographic, health insurance coverage (less in EU, but like US health reassurance companies)

• Racial/ethnic disparities in health outcomes

Health literacy

• maybe some ppl don’t understand etc: display and phrased very important

• for example; the letter and envelop for colorectal screening

Cultural barriers

Environmental impact

Cancer screening: PARTICIPATION

Decreasing trend observed in various European countries over last few years

• Lowest point during COVID-19 pandemic and only slight recovery of participation in the Netherlands

=> Low screening participation meaningfully reduces the effectiveness of screening programs!

Multiple factors influence screening participation (3)

• Fear (can work in 2 ways: motivator or avoidance)

• perception of risk

• social influence

Fear as influence of screening participation

Can be a powerful motivator (intention to participate)

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Too much fear can lead to avoidance (lower participation)

Perception of risk as influence in screening participation

• People with higher perceived risk of cancer are more likely to participate

• Emotional sensitivity to probabilities and bias for action

  • Commission bias = tendency to choose active treatment even when watchful waiting is less risky

• People are bad at interpreting risks (relative vs. absolute risks)

• Absolute risks are generally easier to interpret

• Visualizations are helpful and often used in information material

social influence in screening participation

o   Social norms and influence from family, friends, and doctors can significantly impact a person’s decision to get screened

o   Family support may be particularly important in younger individuals

o   Interaction with health professionals may positively affect screening behavior in older individuals

o   High-profile events can meaningfully influence behaviors in other health domains (e.g., COVID-19 pandemic)

Different strategies are used to increase awareness and attendance (5)

• Research, education and information

• adressing cultural barriers (language, aversians, …)

• general opportunities for counseling and to resolve questions (conversation, more info, specialized phone line)

• motivational interviewing

• social marketing

How to implement and improve cancer-screening programs in other countries?

Ideally, conduct large, RCTs to investigate which screening strategies are effective

However, this would be:

o   difficult to set up

o   take a long time (decades)

o   extremely expensive

o   unethical

a way around problems of conducting large RCTS to investigate screening strategies

simulation modelling

simulation modelling (microsimulation)

a way around problems of conducting large RCTS to investigate screening strategies

• Computer program to simulate the life of individuals (from birth to death)

• Uses data such as life expectancy, cancer incidence, screening attendance

  • For the simulation we aggregate and use many information that exists like life expectancy

  • Ok 2 babies, eventually they die, but difference in when they die, life varies

• Simulate many individuals, count outcomes (life-years, colonoscopies, cancer deaths…)

=> Compare strategies

(example: If we go back to savepoint and act what if he does a screening

→ See what is effect of screening: has 4 additional years of life )

EU-TOPIA

Online platform to use country-specific data in a simulation model

Quantify future harms and benefits of different cancer screening scenarios in their country

→ Help governments and medical societies to make better decisions

EU-TOPIA-EAST 3 steps

1. Implement feasible interventions in some regions and monitor short-term screening performance (participation and detection)

2. Estimate resources, health outcomes and cost-effectiveness of scaling up the interventions to a national level

3. Communicate good implementation practices from participating countries to other MIC in Eastern Europe and the Mediterranean

How can we improve screening?

- Develop and implement better screening tests in current screening programs

- Develop effective tests for diseases without current screening programs

- Improve the balance of harms and benefits

Personalization of screening

Goal: Reducing the burden for people with low risk and focus on high-risk groups

«» Now: everyone has same criteria etc → personalize more

Challenges with the personalization of screening

• Requires extensive pilot testing to show benefits

• Focus on high-risk individuals → screening some people more and some people less!

• Screening programs become more difficult to understand for participants

• Some changes may take a long time to be implemented