Environmental Factors Flashcards
What place in the top 10 most commonest cancer in the world is mouth cancer?
6
What type of cancer accounts for 90% of mouth cancers?
squamous cell carcinoma
are men or women more likely to get mouth cancer
Men 2x more likely
True or false: mouth cancer is more common than testicular and cervical cancer combined?
true
What is the biggest risk factor for oral cancer?
tobacco
In combination, alcohol and tobacco increase your risk of mouth cancer by what?
24 times
What genetic conditions predisposes a patient for mouth cancer?
Fanconi’s anaemia - progressive deficiency of all bone marrow production of blood cell
Dyskeratosis Congenita - inherited bone marrow failure
What autoimmune condition can predispose a patient to mouth cancer?
Lichen Planus
Where is the most common site for mouth cancer?
Tongue and floor of the mouth
How is alcohol a risk factor for oral cancer?
Alcohol is metabolised to acetaldehyde = mutagen and carcinogen
It can be broken down by bacteria in the oral cavity and salivary glands - exposure to acetaldehyde
In combination with tobacco:
- acts as a solvent for carcinogens in tobacco
- also causes thinning/atrophy of the mucosa making it more permeable for the carcinogens
What is a current smokers relative risk of mouth cancer?
RR 3.4
How long after qutting smoking do you reduce the risk back to a non-smoker?
20 years
What cancer causing chemicals does tobacco contain?
Polycyclic aromatic hydrocarbons (PAH) - e.g. benzopyrene
Arsenic
Nitrosamines
acrolein
Hydrogen cyanide
What can be a source of acetaldehyde (carcinogen and mutagen)?
Alcohol
Tobacco
Bacteria (can produce its own source of ADH) - poor OH
Food?? - overly ripe foods
What are the alcohol recomendations?
Daily limit - 2 units
Weekly limit - 14 units
Binging - Male: >8 units, Female: >6 units
what enzyme converts ethanol to acetaldehyde?
alcohol dehydrogenase (ADH)
Why was the alcohol limit lower in women?
Women have higher blood alcohol levels due to lower gastric ADH activity (the enzyme that breaks down ethanol)
Women have higher proportion of body fat and less water = higher conc of alcohol
If a male and female drank the same amount of alcohol how much higher would a womens blood alcohol levels be?
1/3rd higher
What lip is UV light most likely to cause cancer in?
the lower
