Q3 Colorectal Cancer

Question 1

Key stages of colorectal cancer overview

Answer 1

Develops in different stages
Single cell cancer and then grows to form a tumour and cancerous damaging the cells around it

Question 2

Cancer Cell formation

Answer 2

Single genetic variation
Survives due to Darwin effect suggesting it either lives longer, proliferates quicker, avoid cell death
This advantage causes more cells to grow and this can lead to further mutations

Question 2

Tumour Colorectal Cancer Formation

Answer 2

Hyper-proliferation (non-cancerous)
Large adenoma polyps
If continue to grow from here will become cancerous and damages cells around it

Question 3

Medical conditions that may increase risk of Colorectal cancer

Answer 3

p53 mutation
APC

Question 4

p53 mutation

Answer 4

Error in code for cell regulation resulting in an increased risk in a tumour becoming cancerous

Question 5

APC

Answer 5

Increase risk of hyper-proliferation forming

Question 6

Intro to evidence implicating a role for diet in aetiology

Answer 6

70% of cases appear to be sporadic and without genetic reason
Major reason will be the environment of the cell
One major environmental impact of colon is our diet

Question 7

Global cancer update

Answer 7

Role is to analyse all literature regarding colon cancer as to its scientific value and update findings to summarise different risks
Evidence also separated into convincing, probable and limited suggestive

Question 8

Convincing Evidence for increased risk

Answer 8

Diet high in processed meat
High Body fat percentage
Alcohol intake

Question 9

Convincing Evidence decreased risk

Answer 9

Physical Activity

Question 10

Swedish Conscript Study

Answer 10

Longitudinal study
If obese at 18 increases risk of colon cancer later in life
Large sample size
Mostly male
Military trained have a higher level of fitness

Question 11

Ning et al

Answer 11

Obesity review
Every 5 points higher in BMI resulted in 18% increased risk of Colon Cancer
Systematic review supports Swedish Conscript Study
Meaning results are replicable

Question 12

Fibre

Answer 12

Asides from someone’s weight the type of food eaten is also important

Question 13

Epic data

Answer 13

High fibre diet reduces risk of colon cancer.
Believed it is due to butyrate intake
Provides energy for gut microbiome and prevents it from utilising gut mucosal layer for energy.
EPIC large observation study
Theory can be suggested but no way to determine if it is correct

Question 14

Why do we need RCTs for cancer

Answer 14

Observational studies can be quite heavily relied on.
Useful for initial hypothesis but to understand mechanisms need RCT

Question 15

Unethical

Answer 15

Main challenge with RCT is it is unethical to give someone cancer or give someone a diet we think might increase risk of cancer
SO RCTs have to focus on preventative measures
Preventative measures in diet are often hard to follow than a standard diet
Overcome with continued educational intervention

Question 16

Blinding

Answer 16

During pharmaceutical intervention double blind participants and researchers
However, with diet it is almost impossible to blind someone to what group they are in.
Have to consider risk of placebo effect

Question 17

Who takes part in the trial

Answer 17

Older individuals - million women study
Cancer is complex disease that starts forming earlier in life