17. ONCOLOGY 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 use about 200 times more glucose for their metabolism than healthy cells and they have many more glucose receptors in their membrane.
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 suppress the immune system and the function of tumour suppressor genes
e. Alcohol - can cause DNA damage and interfere with hormone balance and lead to mouth, oesophageal, breast and colorectal cancer
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 support 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)
Describe the differences between a benign breast mass and a malignant breast mass
A benign breast mass presents with breast pain / tender masses or nodules. They are also mobile, smooth and with regular borders.
Malignant breast masses are usually not painful and present as fixed lumps with possible overlying skin changes like dimpling or orange peel appearance.
List two nipple/breast changes observed in breast cancer
Painless, unilateral fixed lump Overlying skin changes: Dimpling and orange peel appearance Asymmetry of breasts Inverted and discharging nipple Enlarged axillary lymph nodes
Describe the role of oestrogen in breast cancer
Most breast tumours are oestrogen dependent and 80% of the receptors are usually for oestrogen, a hormone which promotes growth. Thus, high oestrogen exposure increases the risk of breast cancer.
What is meant by ‘triple negative’ breast cancer?
When there are neither oestrogen, progesterone or epidermal growth factor receptors in the tumour which means that the biological treatments targeting these would be ineffective. This is generally an aggressive type of breast cancer.
Explain how a longer reproductive life could increase the risk of breast cancer
A longer reproductive life (early menarche and late menopause) provides higher oestrogen exposure
Name two genetic mutations which may increase the risk of breast cancer
Mutations on the BRCA1 and BRCA2 genes
Explain why aluminium and parabens may increase the risk of breast cancer
Aluminium, which is in many antiperspirants, may be absorbed and cause oestrogen-like hormonal effects.
Parabens can also mimic oestrogen.
Describe the main difference between ‘mammography’ and ‘thermography’.
Mammography uses x-ray radiation directed into the breast tissue to detect larger and calcified tumours.
Thermography uses infrared imaging to detect areas of higher temperature, indicating possible angiogenesis in a tumour.
Name one hormone strongly associated with ovarian cancer
Oestrogen
List four risk factors for ovarian cancer
Family history BRCA1 and 2 genes Long reproductive life HRT Poor lifestyle: Smoking, obesity, lack of exercise Talcum powder
List two characteristic signs/symptoms of ovarian cancer
Vague abdominal discomfort and bloating
Abdominal mass with pelvic pain
Late symptoms: changes in bowel habits (metastasis)
Name two risk factors for cervical cancer
Persistant HPV infection
Sexual behaviour (multiple partners, younger age)
Smoking
Name two characteristic signs and/or symptoms of cervical cancer
Abnormal vaginal bleeding (after intercourse, metorrhagia)
Vaginal discharge
White/red patches on cervix
List two characteristic signs/symptoms of liver cancer
Jaundice
Ascites
Hepatomegaly
Pruritus
Describe the pathophysiology of liver cancer due to:
a. Liver cirrhosis
b. Hepatitis B/C
a. In liver cirrhosis, the toxins built up from alcohol leads to necrosis of liver tissue which give rise to chronic inflammation and cell proliferation.
b. In hepatitis B/C there is viral integration into the host genome which lead to DNA deletions and the activation of oncogenes.
List two dietary risk factors for gastric cancer
Diet rich in salted, pickled and smoked foods (N-nitroso compounds)
Low fruit and vegetable diet
Name one diagnostic tumour marker for gastric cancer
CA19-9
CEA
Describe two differences in the signs/symptoms associated with ‘early stage’ and ‘advanced stage’ gastric cancer
In early stages the symptoms are quite vague, but include persistent indigestion, frequent burping, heartburn, bloating, feeling full quickly and abdominal discomfort.
In advanced stages there is black blood in stools (melaena), loss of appetite, weight loss, tiredness, anaemia and jaundice.
List one red flag symptom associated with oesophageal cancer
Difficulty swallowing (dysphagia).
List two lifestyle risk factors for the development of oesophageal cancer
Smoking
Alcohol consumption
Obesity
Low fruit and veg diet
List two causes of pancreatic cancer
Smoking, Age, Family history
H. Pylori
Diabetes
Chronic pancreatitis
Describe the pain associated with pancreatic cancer
Epigastric pain radiating to the back
List two characteristic signs/symptoms of prostate cancer
Urinary symptoms: Dribbling, incomplete emptying
Nocturia and haematuria
Explain the relevance of back pain in prostate cancer
Back pain can indicate bone metastases.
List four factors (not age) that increase the risk of prostate cancer
Diet: High red meat, refined sugar and dairy intake
Ethnicity: Men of black ethnicity are at highest risk
Family history
Genetics: BRCA1/2
Obesity
A patient displays the following symptoms:
‘Painless haematuria, increased urinary frequency, urgency, dysuria, lower spine pain’
What pathology could this patient be experiencing?
Bladder cancer
Explain how smoking can contribute to bladder cancer
Carcinogens from cigarette smoke is detoxified from the blood into urine and while being pooled in the bladder, can cause mutations.
Describe two characteristic signs/symptoms of testicular cancer
Hard, fixed, painless unilateral mass on testes.
Dragging sensation and a dull ache
List two risk factors that increase the risk of skin cancer
Excessive UV light exposure
Chemicals in sunscreens
List two body locations commonly associated with skin cancer
Head and neck or back
Describe the lesions associated with:
a. Basal cell carcinoma
b. Squamous cell carcinoma
c. Melanoma
a. Basal cell carcinoma: Smooth, raised pearly bump
b. Squamous cell carcinoma: Red, scaling thickened nodule which can be hard with central necrosis
c. Melanoma: Brown/black lesions occasionally pink or red in colour
Describe five warning signs that might indicate a melanoma
Changes in size, shape, colour, elevation of a mole or a new mole
Describe what is meant by ‘osteosarcoma’
Ostoesarcoma is a malignant bone tumour
Describe one feature of the pain associated with osteosarcoma
Malignant bone tumours cause worsening pain that becomes unremitting and even wake a patient at night.
Describe the difference between ‘high grade’ and ‘low grade’ brain tumours.
Brain tumours that grow rapidly and aggressively are often referred to as high-grade tumours whilst slower replicating tumours are ‘low-grade’.
Describe the headache associated with a brain tumour
Unexplained headaches that are worse in the mornings
List one sign of a brain tumour (not headache)
Papilloedema
Using definitions, compare ‘lymphoma’ with ‘leukaemia’
Lymphoma is a malignancy of lymphatic cells while leukaemia describes a group of bone marrow cancers, characterised by an abnormal over-production of leukocytes.
Name one lymphocyte commonly involved with lymphoma
B-lymphocytes
List one viral risk factor found in 50% of patients with Hodgkin’s lymphoma
EBV (Epstein-Barr virus)
List two characteristic signs/symptoms of lymphoma
Enlarged and asymptomatic lymph node in the neck.
Drenching night sweats, fever, weight loss
Chest discomfort, cough, dyspnoea
Discuss the differences between acute and chronic leukaemia.
Acute leukaemia can affect all ages and has a rapid onset and aggressive course. There are more immature leukocytes with variable count and thrombocytopaenia and anaemia is prominent. Lymph node enlargement and splenomegaly is mild.
Chronic leukaemia has an insidious onset and usually affects adults. The leukaemic cells are mature and anaemia and thrombocytopenia is mild. The leukocyte count is increased with prominent display of lymph node enlargement and splenomegaly.
How does leukaemia affect blood cells?
The uncontrolled proliferation of leukocytes, results in supressed erythrocyte production (anaemia) and thrombocytes (thrombocytopenia).
List four characteristic signs/symptoms of leukaemia.
Malaise (fatigue) Anaemia (pallor) Frequent infections Easy bleeding/bruising Fever Weight loss Splenomegaly Lymph node enlargement
List the four types of leukaemia
- Acute Myelogenous leukaemia (AML)
- Acute Lymphocytic leukaemia (ALL)
- Chronic Myeloid leukaemia (CML)
- Chronic Lymphocytic leukaemia (CLL)
How is leukaemia diagnosed?
Blood tests: FBC, low thrombocytes, variable leukocytes, blood film
Bone marrow biopsy
What age group is commonly affected by testicular cancer?
15-35 year olds
Who is commonly affected by primary osteosarcomas?
Teenagers and young adults.
