Session 10 Flashcards
What are the four most common cancers accounting for over half of all new cancers in the UK?
Breast
Lung
Prostrate
Bowel
All carcinomas
Why are the four most common cancers all carcinomas?
Epithelium is a labile tissue with a high turnover —> increased chance for mutation
The great majority of cancer is diagnosed amongst which ages?
Over 65
In children younger than 14, which cancers are most common? (3)
Leukaemias
CNS tumours
Lymphomas
What type of cancer is the biggest cause of cancer-related deaths in the UK?
Lung cancer
The survival for different cancer types in the UK is very variable.
Name 3 cancers that have a particularly high 5 year survival rate
Testicular
Melanoma
Breast cancer
The survival for different cancer types in the UK is very variable.
Name 3 cancers that have a particularly low 5 year survival rate
Pancreas
Lung
Oesophagus
What factors can be used to predict the outcome of malignant neoplasms on individuals? (7)
Age General health status Tumour site Tumour type Grade Stage Availability of effective treatments
The commonest method for assessing the extent of a tumour is…
The TNM staging system
What does the letters in the TNM staging system stand for?
Tumour
Nodes
Metastases
What does the T in TNM stand for? What does it describe? How is it expressed?
Tumour
Size of the primary tumour
T1 - T4 (increasing size of tumour)
What does the N in TNM stand for? What does it describe? How is it expressed?
Nodes
Extent of regional node metastasis
N0 - N2 (increasing spread in regional nodes, N0 = no presence in regional nodes)
What does the M in TNM stand for? What does it describe? How is it expressed?
Metastases
Extent of distant metastatic spread
M0 or M1
For a given cancer the T, N and M status are then converted into a…
Stage
Cancer is staged in stages…
I - IV
Describe the broad status of cancer in stages I - IV
Stage I - early local disease (T, 1 or 2)
Stage II - advanced local disease (T, 3 or 4)
Stage III - regional metastasis (T, any, N, 1+)
Stage IV - advanced disease with distant metastasis (T, any, N, any, M1)
Which system is used for the staging of lymphoma?
Ann Arbor staging
What is Ann Arbor staging used for?
The staging of lymphoma
Describe the Ann Arbor staging of lymphoma
Stage I - single node region
Stage II - two separate regions on one side of the diaphragm
Stage III - spread to both sides of the diaphragm
Stage IV - disseminated involvement of one or more extra-lymphatic organ (e.g. Bone marrow, Lung)
Staging of cancer is a powerful predictor of…
Survival
What staging system is used for colorectal carcinoma?
Dukes staging
Describe the Dukes staging of colorectal carcinoma
Dukes’ A - invasion into but not through the bowel
Dukes’ B - invasion through the bowel wall
Dukes’ C - involvement of lymph nodes
Dukes’ D - distant metastases
Tumour grade describes…
The degree of differentiation of a neoplasm
Which is more standardised, grading or staging of cancer?
Staging of cancer
How is the grading of malignant neoplasms expressed?
G1 - G4
Describe what the stages G1-G4 mean in the grading of malignant neoplasms
G1 - well-differentiated
G2 - moderately differentiated
G3 - poorly differentiated
G4 - undifferentiated or anaplastic
Which system is used for the grading of breast carcinoma?
Bloom-Richardson system
What does the Bloom-Richardson system assess in the grading of breast carcinoma? (3)
Tubule formation
Nuclear variation
Number of mitoses
Tumour grade is important for…
Give 3 examples of types of cancer where tumour grading is particularly important
Planning treatment and estimating prognosis
Lymphomas
Breast
Prostate
Name 5 types of treatment for cancer
Surgery Radiotherapy Chemotherapy Hormone therapy Treatment targeted to specific molecular alterations Treatments targeting the immune system
What is the mainstay of treatment for most cancers?
Surgery
What is adjuvant treatment?
Treatment given after surgical removal of a primary tumour to eliminate subclinical disease
What is neoadjuvant treatment?
Treatment given to reduce the size of a primary tumour prior to surgical excision
Radiation therapy kills proliferating cells by.. (2)
Triggering apoptosis
Interfering with mitosis
Why is radiotherapy given in fractioned doses?
To minimise normal tissue damage
X-rays or other types of ionising radiation are used in radiation therapy to kill rapidly dividing cells.
These cells are typically in which phase of the cell cycle?
G2
How does high dosage radiation therapy kill cancer cells?
Causes either direct or free-radical induced DNA damage detected by cell-cycle checkpoints, triggering apoptosis
Double stranded DNA breakages cause damaged chromosomes that prevent…
M phase from completing
Chemotherapy drugs affect which type of drugs?
Proliferating cells
Do chemotherapy drugs act in a specific or non-specific way?
Non-specific
Give 4 different classes of chemotherapy agents
Antimetabolites
Alkylating and platinum-based drugs
Antibiotics
Plant-derived drugs
How do antimetabolites work as chemotherapy agents?
Give an example
Mimic normal substrates involved in DNA replication
Fluorouracil
How do alkylating agents/platinum based drugs work as chemotherapy agents?
Cross-link the two strands of the DNA helix
Give an example of an antibiotic that is used in chemotherapy and its mechanism of action
Doxorubicin
Inhibits DNA topoisomerase
Give an example of a plant-derived chemotherapy agent and its mechanism of action
Vincristine
Blocks microtubule assembly and interferes with mitotic spindle formation
Give some examples of side effects of chemotherapy due to the non-specific action of the agents
Hair loss - hair follicles damaged
GI upset - GI tract
Immunosuppression - bone marrow suppression
Is hormone therapy a relatively toxic or non-toxic treatment for certain malignant tumours
Non-toxic treatment
What is a disadvantage of hormone therapy?
It has limited scope and can only be used for some malignancies
Give an example of a cancer that hormone therapy is used to treat and how it works
Hormone receptor-positive breast cancer
Selective oestrogen receptor modulators (SERMs) such as tamoxifen bind to oestrogen receptors preventing the binding of oestrogen
Give an example of a SERM (selective oestrogen receptor modulator)
Tamoxifen
Androgen blockage is used as hormone therapy for the treatment of…
Prostate cancer
Give two examples of drugs that work by targeting cancer-specific molecular alterations in cells
What are usually the cancer-specific alterations?
Herceptin (Trastuzumab)
Gleevec (Imatinib)
Herceptin can be given in the treatment of which type of cancer?
How does it work?
Breast cancer
Many breast cancers have over-expression of the HER-2 gene. Herceptin can block the HER-2 signalling.
Gleevec can be given in the treatment of which type of cancer?
How does it work?
Chronic myeloid leukaemia
Inhibits the fusion protein produced by an oncogene
Give an example of a drug that blocks immune checkpoints
Nivolumab
Tumour markers allow the monitoring of…
Cancer burden
What are tumour markers useful for?
Monitoring of tumour burden
Give 4 examples of types of tumour markers
Hormones
Oncofetal antigens
Specific proteins
Mucin/glycoproteins
What is the aim of cancer screening?
To detect cancers early as possible when the chance of cure is the highest
Name three problems associated with cancer screening
Lead time bias
Length bias
Overdiagnosis
Describe what is meant by the lead time bias seen in cancer screening
Screening may not affect survival but may affect survival statistics, as it was detected earlier, so will survive longer with the disease according to statistics - appearing that screening was effective
Describe what is meant by the length bias seen in cancer screening
Slower growing tumours are more likely to be detected
In the UK there are established national screening programmes for which cancers?
Cervical
Breast
Bowel
What colour does immunohistochemistry stain?
Brown
What does H&E stain contain?
Haemotoxylin
Eosin
What does H&E stain in a cell?
Haemotoxylin stains the nucleus most strongly blue
Eosin stains the cytoplasm/ECM most strongly pink
What is histology? What is cytology?
Histology - study of sections of tissues
Cytology - study of disaggregated cells in fluid
Give three examples of histological procedures
Core biopsies
Cancer resection specimens
Excised skin lesions
Give three examples of cytological procedures
Cervical smears
Fine needle aspirates of breast/thyroid/salivary glands
Urine
Give three advantages of using histological investigations rather than cytological investigations
Often therapeutic as well as diagnostic
Can assess tissue architecture as well as cell atypia
Can differentiate invasive from in situ disease
Give three advantages of using cytological procedures over histological procedures
Faster and cheaper
Non-invasive/minimally invasive
Can be used for cells in fluid
How do lymphocytes typically appear under a microscope?
High nucleus:cytoplasm ratio, so stain dark blue/purple
Lymphocytes have a high nucleus:cytoplasm ratio and so stain darkly blue under a microscope. Dark staining and the presence of many cells in a microscope slide may indicate…
Inflammation
Neoplasm
How do neutrophils appear under a microscope?
With a multi-lobe nuclei (polymorphs)
How do eosinophils appear under a microscope?
Sunburnt face with glasses (bilobe nucleus, red cytoplasm)
How do macrophages appear under a microscope?
With a kidney shaped nucleus to one side and foamy cytoplasm
Name the cells that are commonly seen in lymphoma
Reed-Sternburg cells
> ____ % occlusion of coronary arteries results in a risk of sudden cardiac death
80
