Oncology 17 Flashcards
What is oncology
Study and treatment of cancer
What is the name of a physician who practices oncology?
Oncologist
What is the name of a mass of tissues than grows faster than normal in an uncoordinated manner?
Neoplasm
What is a tumour
Means ‘swelling’ in Latin. Describes a mass of growth of tissue - can be malignant or benign.
3 ways to tell if a tumour is malignant?
It no longer responds to normal growth factors
Grows faster than normal
Grows in an uncoordinated manner
Why is cancer more common in developed countries?
Environment
Lifestyle
Diet
Medications
Drugs
How many deaths per year does cancer cause globally?
10 million
What is mitosis?
The growth and repair of somatic cells
What is meiosis?
The process that produces sex cells (gametes)
What do non-cancer cells have in common?
They are differentiated and specialised
What happened if cells become disorganised and grow in an uncontrolled manner?
Their function is lost
What is cancer the result of?
An underlying cause
Genetic mutations
Patients genes with the environment
In cancer, what happens to tumour suppression genes?
They become inactivated and new genes called oncogenes are formed
What is angiogenesis?
New blood cells form
As malignant cells can only grow 1-2mm without blood supply
3 environments cancer cells thrive in and why
Acidic - red meat, processed, diary, sugar & smoked foods
Anaerobic environment - lacking oxygen. Stress, breathing, diet and exercise
Glucose-rich - malignant cells dependent on glucose.
What is contact inhibition
Proteins produced by cells that prevents cells diving beyond the space available
What happens to contact inhibition in cancer?
Cancerous cells lose contact inhibition
What is a change in generic information called?
Mutation
What is a mutagen? Give some examples
An agent that changes the genetic info
Environment, chemicals, radiation, viruses, inflammation, immunity
What is a carcinogen and give some examples?
A cancer-causing agent - nitrosamines, heavy metals, asbestos, X-rays
What is carcinogenesis?
Process by which normal cells are transformed into cancel cells
What percentage of cancers are attributed to environment and lifestyle?
90-95%
How long can some tumours take to develop?
20-40 years
Cancer risk factors
Genetic BRCa, family history
Chronic inflammation
Radiation
Smoking
Drugs & cosmetics
GIT dysfunction
Vitamin D deficiency & thyroid
Stress
Sexual behaviour
Excess alcohol
Obesity
Metal toxins
Medications
Vaccine ingredients
Why is obesity a cancer risk factor?
Excess body fat changes hormone metabolism - increases oestrogen - drives oestrogen positive tumours
Why is chronic inflammation a cancer risk factor and give 2 pathology examples
Promoted proliferation of cancer cells
Inflammatory bowel disease and gastro-oesophageal reflex diseases
Why is GIT dysfunction a cancer risk factor?
Liver - detoxifies substances
Intestines - excrete body waste, absorb nutrients and immune function
What a dietary risk factors of cancer
Red meats
Burnt food
Low fibre
N-nitroso compounds eg cured meat
Refined sugar
Dairy
Table salt, pesticides and aspartame
Why is diary a cancer risk factor?
Pro-inflammatory and contains insulin-like growth factors
Why is a low fibre diet a cancer risk
Fibre is high in phytochemicals and clear toxins and hormones such as oestrogen
In chronic immunodeficiency what is deficient which would normally destroy abnormal cells
Cytotoxic t-lymphocytes
Natural killer cells
Macrophages
How the host’s immune system compromised in HIV?
HIV targets CD4 cells (t-helper and macrophages) which compromise the hosts immune system
How does stress compromise the immune system
Chronic stress elevates cortisol levels which suppress the immune system
Describe a usual benign tumour
Differentiated cells
Appear similar to normal cells so may be functional
Reproduce at a higher rate than normal
Often encapsulated
Grow slowly
Usually not life-threatening
Example of when a benign tumour can be life threatening
Brain tumour that raised intracranial pressure
Key points about malignant tumours
Usually undifferentiated, non-functional cells, varies shapes and sizes and large nuclei
Reproduce free
Not encapsulated
Often systemic
Life-threatening
What do cancer grades measure?
Degree cell differentiation / abnormality
