S10: neoplasia (4)

Question 1

List the most common types of cancer in adults and children and the leading causes of cancer-related death

Answer 1

Men – prostate, lung & bowel
Women – breast, lung & bowel
Children – leukaemia, CNS & lymphoma
Leading causes of death: lung, breast/prostate & bowel

Question 2

Describe what is meant by tumour staging and give examples of different systems

Answer 2

Measure of the overall burden of the malignant neoplasm
TNM staging system = standardised across the world
T = size of primary tumour, N = extent of regional lymph node involvement & M = metastatic spread via the blood
Stage 1 = early local disease, stage 2 = advanced local disease, stage 3 = regional metastasis & stage 4 = advanced disease with distant metastasis (varies with each cancer)
Eg. Ann-arbor (lymphoma)

Question 3

Describe what is meant by tumour grading

Answer 3

Describes the degree of differentiation of a neoplasm 
G1 = well-differentiated
G2 = moderately differentiated 
G3 = poorly differentiated 
G4 = undifferentiated/anaplastic 
Eg. Bloom Richardson (breast)

Question 4

List the different types of treatments for neoplasms

Answer 4

Surgery
Radiotherapy
Chemotherapy 
Hormone therapy 
Immunotherapy 
Treatments targeted to specific molecular alterations

Question 5

Define adjuvant & neoadjuvant treatment

Answer 5

Adjuvant = treatment is given after surgical removal of a primary tumour to eliminate subclinical disease
Neoadjuvant = treatment is given prior to surgical excision to reduce the size of the tumour

Question 6

Explain radiation therapy

Answer 6

Kills proliferating cells by triggering apoptosis/interfering with mitosis (either direct or free-radical induced DNA damage)
Given in fractioned doses to minimise normal tissue damage
Kills rapidly dividing cells in G2 of cell cycle
Double stranded DNA breakages causes damaged chromosomes that prevent M phase from completing correctly

Question 7

Describe different types of chemotherapy

Answer 7

Antimetabolites = mimic normal substrates involved in DNA replication
Alkylating & platinum-based drugs = cross link the two strands of the DNA helix (cisplatin)
Antibiotics = inhibits DNA topoisomerase needed for DNA synthesis (doxorubicin)

Question 8

Explain the action of tamoxifen (hormone therapy)

Answer 8

Binds to oestrogen receptors -> blocking the receptors which stops oestrogen from binding
Used for hormone receptor positive breast cancer

Question 9

Give examples of drugs which target oncogenes

Answer 9

Herceptin

Imatinib

Question 10

Explain immunotherapy

Answer 10

Targets the immune system to help to fight cancer by recognising & killing cancer cells
Cancer immunity cycle highlights points where immune treatments can be used

Question 11

What are tumour markers? Give examples

Answer 11

Various substances released by cancer cells into the circulation
Can be measured for:
-diagnosis
-monitoring tumour burden
-assess recurrence
Examples include: hCG – testicular tumours, alpha fetoprotein – hepatocellular carcinoma, prostate specific antigen – prostate carcinoma & CA125 – ovarian cancer

Question 12

What screening programmes are available in the UK?

Answer 12

Breast screening 
-women, 47 – 73 years of age, every three years 
-mammogram 
Cervical screening (smear test)
-women, 25-64 
-every 3 years for women aged 25-49 
-every 5 years for women aged 50-64 
Bowel screening 
-home testing kit: men & women 60-74
-bowel scope screening: offered to men & women at age of 55 in some parts of England

Question 13

List some problems with screening programmes

Answer 13

Lead time bias
Length time bias
Overdiagnosis