17. Oncology Workshop Flashcards
Define the following terms
a) Neoplasm
b) Tumour
a) A mass of tissue that grows faster than normal in an uncoordinated manner.
b) Literally means ‘swelling’ but is used to describe a mass/growth of tissue.
Why do developed countries display higher cancer rates.
Due to the influence of environment, lifestyle, diet, medications and drugs.
Discuss: “Cancer is the result of underlying causes”
Cancer is the end result of genetic mutations that occur as a result of interaction with the environment. When tumour suppression genes are inactivated and proto-oncogenes turn into oncogenes, they cause the overproduction of growth factors and increase cell division, resulting in malignant neoplasms.
Define ‘angiogenesis’
Angiogenesis is the process through which new blood vessels are formed from pre-existing blood vasculature. While this is a normal and vital process in the body, it is also a fundamental step in the transition of tumours from benign to malignant.
Describe how the following environments allow cancer cells to thrive:
a. Acidic environment
b. Anaerobic environment
c. Glucose-rich environment
a. Cancer cells thrive in an acidic environment and not in an alkaline environment. Diets high in red meat, processed foods, dairy, sugar, salt and smoked foods adds to the acidity of the body.
b. An environment lacking in oxygen is favourable for the formation of cancer cells since they can meet their energy needs by fermentation instead of respiration. A lifestyle with high stress, lack of exercise, shallow breathing contribute to this state.
c. Malignant cells are dependant on glucose for their metabolism and they have many more glucose receptors in their membrane than healthy cells.
Explain the relationship between ‘contact inhibition’ and cancerous cells
Healthy cells produce proteins which serve as stimuli for contact inhibition which stops the cells dividing beyond the space available. Cancerous cells lose their contact inhibition and continue to grow
Define ‘mutation’
Mutation is the change in genetic information (DNA sequence/number)
List four mutagenic agents
- Chemicals (environmental, household, drugs, vaccines)
- Radiation (x-rays, microwaves, mobile phones)
- Inflammation
- Viruses (Hepatitis, HPV, HIV)
- Defective immunity
- Stress / emotional trauma
Describe how the following factors could increase the risk of cancer:
a. Chronic inflammation
b. Smoking
c. Gastrointestinal dysfunction
d. Chronic stress
e. Alcohol
f. Obesity
g. Red meats
h. Low fibre
i. Refined sugar
j. Dairy
k. Immune suppression
a. Chronic inflammation - promotes the proliferation of cancer cells
b. Smoking - causes one mutation every 15 cigarettes
c. Gastrointestinal dysfunction - of the liver and intestines causes suboptimal detoxification, excretion of waste products, absorption of nutrients and immune function.
d. Chronic stress - elevates cortisol levels and suppresses the immune system and the function of tumour suppressor genes
e. Alcohol - can cause DNA damage and interfere with hormone balance
f. Obesity - Excess body fat changes hormone metabolism, leads to higher oestrogen, which drives the growth of oestrogen-positive tumours
g. Red meats - processed and chargrilled, smoked and cooked at high temperatures, meat increases the risk of colorectal, gastric, pancreatic, prostate, breast and bladder cancers.
h. Low fibre - Fibre is high in phytochemicals that clears toxins and hormones such as oestrogen through the bowels; lack of fibre can lead to constipation and reabsorption of waste products.
i. Refined sugar - feed cancer cells and promote growth by increasing acidity
j. Dairy - is pro-inflammatory and contains IGFs that promote tumour growth.
k. Immune suppression - creates an environment for cancerous cells to thrive in. A healthy, functioning immune system is essential to provide protection against malignant cell development.
Describe three key differences between ‘benign’ and ‘malignant’ tumours
- Benign tumours contain differentiated, functional cells while malignant tumours contain undifferentiated cells that are non-functional.
- Benign tumours are encapsulated, limiting their spread. Malignant tumours are not encapsulated and infiltrate other tissues (metastasise).
- Benign tumours grow slowly and do not spread to cause systemic effects. Malignant tumours reproduce much faster and their effects are often systemic as they can spread to other organs.
What is the difference between ‘grading’ and ‘staging’ of cancer?
Grading is the measure of the degree of cell differentiation/abnormality and it ranges from Grade 1 (normal) to Grade 4 (very abnormal cell architecture).
Staging is the classification of malignant tumours according to the extent of the disease at the time of diagnosis. It ranges from Stage 0 (pre-cancerous) to Stage IV (Distant metastasis).
Explain the TNM staging system
T = Tumour (1-4): Size of primary tumour N = Node (0-3): Degree of lymph node involvement M = Metastasis (0-1): 1 indicates metastasis X = cannot be assessed
List two local effects of a tumour
- Tumours can compress blood vessels, leading to necrosis of surrounding tissues.
- Obstruction may occur of tubes or ducts in the body.
Describe the following systemic effects in cancer:
a. Cachexia
b. Para-neoplastic syndrome
a. Cachexia is weight loss and muscle wastage
b. Symptoms that occur at a site that is distant from a tumour/metastasis such as lung cancer producing ACTH which leads to Cushing’s syndrome.
List two ways by which malignant tumours spread in the body
Via venous or lymphatic flow
List four common sites of metastasis in the body
Bone
Liver
Lungs
Brain
What kinds of diagnostic tests are used in cancer diagnosis?
- Blood tests
- Tumour Markers
- Imaging
- Biopsies
True or false: “Tumour markers can provide an absolute diagnosis of cancer”
False. Tumour markers MUST be used within the context of the patient presentation and other clinical findings. Some markers are found in non-cancerous conditions and some are more sensitive and indicative of certain types of cancer.
List one blood borne tumour marker which may be elevated in:
a. Colorectal cancer
b. Prostate Cancer
a. CEA (Carcinoembryonic Antigen)
b. PSA (Prostate Specific Antigen)
Name one tumour marker used in the diagnosis of testicular cancer
hCG (human Chorionic Gonadotropin)
Name a tumour marker elevated in:
a. Ovarian cancer
b. Breast cancer
a. CA-125
b. CA15-3
Name one stool tumour marker used to diagnose testicular cancer
M2-PK
Describe the difference between ‘curative’ and ‘palliative’ treatment approaches in cancer
Curative treatment is used in an attempt to resolve the malignancy whilst palliative care is focused on reducing the severity of symptoms in order to enhance quality of life.
What are the following surgical treatments better known as:
a. Removal of testes
b. Removal of breast
c. Removal of prostate gland
a. Orchiectomy
b. Mastectomy
c. Prostatectomy
Why does radiotherapy cause immunosuppression?
Radiotherapy affects those cells which divide most rapidly, whether healthy or malignant. This includes the depression of bone marrow cells which leads to aplastic anaemia and pancytopenia which induces a state of immunosuppression.
List two adverse effects of chemotherapy
Bone marrow depression Hair loss Diarrhoea Vomiting Pruritis Organ damage Cancer
What are the following cancers called?
- Cancer which forms in the epithelial tissue
- Cancer which develop in the connective tissue
- Cancer which evolve in the blood and/or bone marrow
- Carcinomas
- Sarcomas
- Leukaemias
List the main cause of lung cancer
Smoking
Why would a person with HIV be at greater risk of developing Kaposi’s sarcoma?
HIV targets CD4 cells, which compromises the host’s immune system.
List three characteristic signs/symptoms of lung cancer (not weight loss)
- Dry, persistant cough
- Dyspnoea and chest pain
- Haemoptysis (bloody sputum)
- Clubbing of nails
- Voice hoarseness
Name three risk factors for the development of colorectal cancer
- Diet high in meat and low in fibre
- Lack of vitamin D
- Polyps
- Family history
List two characteristic signs and/or symptoms of colorectal cancer
- Rectal bleeding and/or mucus in stool
- Colicky abdominal pain caused by obstruction
- Consistent change in bowel habits (diarrhoea / constipation)
