17. Oncology Flashcards
Define ‘oncology’
The study and treatment of cancer / malignant tumours
Define oncologist
A physician who practices oncology
Define neoplasm
A mass of tissue that grows faster than normal in an uncoordinated manner
Define a tumour
Translates to “swelling”
Primarily used to describe a mass/growth of tissue. This growth can be either malignant or benign.
What 5 types of cancer are currently the most common cause of death in the world?
Lung
Colon and rectum
Liver
Stomach
Breast
Where are the highest rates of cancer and why might this be?
In developed countries which emphasises the link to environment, lifestyle, diet, medication and drugs.
How do cancerous cells appear under the microscope?
Disorganised
Growing in an uncontrolled manner.
Cell architecture is lost.
Explain what is meant by ‘angiogenesis’.
The creation of more blood vessels
Describe the genetic mutation that occurs to cause cancerous growth.
Tumour suppression genes become inactivated and new genes called oncogenes are formed that cause the over production of growth factor and increase cell division.
What environment will cancer most thrive in?
Acidic environment
Anaerobic environment
Glucose rich
What external factors can produce acidity in the body?
Red meats
Processed foods
Dairy
Sugar
Salt
Smoked foods
How might the body develop an anaerobic environment?
Stress
Shallow breathing
Diet
Lack of exercise
Why is a glucose-rich environment preferable for cancer cells?
Malignant cells are dependent on glucose for their own metabolism.These cells have many more glucose receptors on their membrane.
What is contact inhibition?
Contact inhibition prevents cells from dividing beyond the space available.
Cancerous cells lose contact inhibition resulting in uncontrolled growth.
Define mutation.
The change in the genetic information (change in DNA sequence / number)
What is a mutagen and list 4 examples?
It’s an agent that changes the genetic information causing a mutation.
- Environmental hazards
- Chemicals
- Radiation
- Viruses
- Chronic inflammation
- Defective immunity
- Stress / emotional trauma
Define carcinogen
Any cancer-causing agent
E.g. heavy metals, asbestos, x-rays, UV rays
Define carcinogenesis
The process by which normal cells are transformed into cancer cells.
What percentage of cancer is attributed to inherited genetic defects?
Only 5-10%
The remaining 90-95% are attributed to environment and lifestyle.
List 5 risk factors (excluding genetics) for cancel
Chronic inflammation
Radiation
Smoking
Drugs and cosmetics
GIT dysfunction
Vit D deficiency
Chronic stress
Sexual behaviour
Compromised immunity
Excess alcohol
Obesity
Excessive exposure to sunlight
Metal toxins
Medications
Vaccine ingredients
Describe how chronic inflammation could increase the risk of cancer
It promotes the proliferation of cancer cells.
Inflammatory bowel disease
Gastro-oesophageal reflux disease
Gastritis
Describe how smoking could increase the risk of cancer
Causes 1 mutation every 15 cigarettes
Describe how GIT dysfunction could increase the risk of cancer
The liver detoxifies substances and the intestines excrete body waste, absorb nutrients and is vital in the body’s immune function. If these aren’t working effectively, toxins can accumulate in the body causing damage.
Describe how chronic stress could increase the risk of cancer
Suppresses the immune system
Describe how alcohol could increase the risk of cancer
It puts extra strain on the liver which is needed to detoxify and eliminate toxins.
Describe how Obesity could increase the risk of cancer
Excess body fat changes hormone metabolosm
This causes higher oestrogen in the body.
This drives oestrogen-positive tumours.
Describe how a low fibre diet could increase the risk of cancer
Fibre is important to help pull waste, toxins, and hormones out of the body. Without these can end up being reabsorbed into the body rather than being eliminated.
Describe how refined sugar could increase the risk of cancer
Feeds cancer cells and promotes growth.
Also increases acidity.
Describe how dairy could increase the risk of cancer
Proinflammatory
Contains insulin-like growth factor (IGF) that promote tumour growth
Describe how chronic immunodeficiency could increase the risk of cancer
A healthy, functioning immune system is essential to providing support against malignant cell development.
Cytotoxic T-lymphocytes, natural killer cells, and macrophages are needed to destroy abnormal cells.
Describe THREE key differences between ‘benign’ and ‘malignant’ tumours.
Benign:
Consist of differentiated cells
Very often encapsulated (cant break off)
Grows very slow in comparison to malignant.
Malignant:
Undifferentiated cells
Not encapsulated so can spread
Cells reproduce much faster
Using definitions explain the difference between ‘grading’ and ‘staging’ of cancer.
Grading is the measure of the degree of cell differentiation / abnormality.
Grade ranges from 1 - 4
Staging is the classification of malignant tumours according to the extent of the disease at the time of diagnosis.
Stage 0 = precancerous
Stage 5 = Distant metastisis
Explain the TNM staging system
Tumour, node, metastasis (TNM)
T is for the size of the primary tumour
scored 1-4
N is the degree of lymph node involvement
Scored 0-3
M is whether there is metastasis
Scored 0 or 1
An X for any of these means it couldn’t or wasn’t assessed.
List TWO local effects of a tumour.
- Compression ofblood vessels leading to necrosis of surrounding tissues.
- Pain caused by pressure or inflammation
- Obstruction may occur in tubes/ducts
- Infection from ulceration or necrosis
Describe the following systemic effects in cancer:
Cachexia
Cachexia is weight loss and muscle atrophy
Normally a later symptom.
Patients may still have a strong appetite.
Describe the following systemic effects in cancer:
Para-neoplastic syndrome
Symptoms that occur at site distant from a tumour or metastases
E.g. lung cancers may produce ACTH leading to Cushing’s syndrome
List TWO ways by which malignant tumours spread in the body.
Blood or lymph
List FOUR common sites of metastasis in the body.
Bone, liver, lungs and brain
Because of their routes to lymph and arteries.
List 4 early signs that may present in cancer patients.
Unexplained weight loss
Anaemia and fatigue
Night sweats
Unusual bleeding
Persistent indigestion / heartburn
Difficulty swallowing
Change in bowel or bladder habits
A solid lump
Swollen lymph nodes
Discuss the following statement:
‘Tumour markers can provide an absolute diagnosis of cancer’.
This is not true - false positives and false negatives are possible.
Tumour markers are 1 possible diagnostic tool
List ONE blood born tumour marker that may be elevated in:
a. Colorectal cancer
b. Prostate cancer
Colorectal cancer =
Carcinoembryonic antigen (CEA)
Low sensitivity and specificity.
Used more for monitoring
Prostate cancer =
Prostate Specific Antigen (PSA)
Normally present in small quantities in the blood.
PSA used to assist in diagnosis or monitor metastasis post-treatment
Name ONE tumour marker used to diagnose testicular cancer.
Human chorionic gonadotrophin (hCG)
Men do not naturally produce this hormone.