Overview of Cancer: L1 Flashcards
(92 cards)
1
Q
What is cancer?
A
Cancer is a group of diseases that are characterised by uncontrolled and spread of abnormal cells. If the spread is not controlled, it can result in death.
2
Q
What is dysplasia?
A
It is the change in shape or morphology or cytology which causes cells to grow into large masses of unusual sizes.
3
Q
What are the steps leading to invasive cancer? Hint 5
A
- Cell with genetic mutation
- Hyperplasia
- Dysplasia
- In situ cancer
- Invasive cancer
4
Q
What is the name of cancer that kills patient and normally what we think of when we refer to cancer?
A
Malignant cancer
5
Q
What is a neoplasm?
A
A tumour
6
Q
What can neoplasms be?
A
Neoplasms can be benign, premalignant or malignant
7
Q
What is the cause of cancer?
A
The main causes of cancer remain largely unknown however there are many factors known to increase risk
8
Q
What are these risk factors?
A
Some of these risk factors are modifiable such as tobacco use and excess body weight, while others are generally unmodifiable such as inherited mutations and immune conditions
9
Q
Is cancer a complicated process?
A
Yes, cancer is a complex disease and it is a sequential series of events leading to it, it is not caused by just one event
10
Q
What is statistic for cancer?
A
1 in 2 get cancer at some point in their life
11
Q
What is the leading cause of death in developed countries?
A
Cancer is the leading cause of death in developed countries and the 2nd leading cause of death worldwide
12
Q
Stats for Cancer in 2018:
A
17 million cancer cases and 9.5 million cancer deaths estimated worldwide by IARC - International agency for research on cancer
13
Q
What are the 3 costs of cancer?
A
Human toll
Financial costs
Costs will increase with growing ageing populations
14
Q
What is a societal concern for cancer?
A
Major societal concern in forthcoming years as ageing populations grow as 1 trillion US dollars per year and this will increase via new targeted therapies, etc.
15
Q
What financial costs are associated with cancer? Hint 3
A
- There are direct costs such as treatment, care and rehabilitation
- Indirect costs such as loss of economic outcomes within morbidity and mortality costs
- Hidden costs such as health insurance and non-medical costs
16
Q
Why is cancer increasing?
A
Main reason is that we are living longer, however lifestyle factors plays a role within this
17
Q
What are the 4 ways that cancer is classified?
A
Cancer is classified by the origin of it such as breast, prostate, lung, etc
Then it is classified by tissue types
Classification by grade takes place
There is classification of cancer by its stage
18
Q
How is cancer classified by tissue types?
A
By being either carcinoma (epithelia) and then falling under: adenocarcinoma (glandular epithelia) or squamous cell carcinoma (squamous epithelia).
Or by being sarcoma such as mesenchymal cells: muscle, bone, cartilage, fat, etc
Then split into Rhabdomyosarcoma, osteosarcoma, chondrosarcoma and liposarcoma
19
Q
What has its own classification?
A
Blood cancers have their own classification
20
Q
What are haematological disorders?
A
They are blood disorders
21
Q
What 3 fall under haematological malignancies?
A
Leukaemia, Lymphoma and Myeloma
22
Q
What is Leukaemia?
A
It is blood cancer which affects bone marrow
23
Q
What is leukaemia split into?
A
Acute lymphocytic leukaemia, acute myeloid leukaemia, chronic lymphocytic leukaemia, and chronic myeloid leukaemia
24
Q
What is Lymphoma?
A
Blood cancer that affects the lymphoid organs
25
What can Lymphomas be split into?
Hodgkin's lymphoma and non-Hodgkin's lymphomas such as indolent or high grade
26
What is myeloma?
It is blood cancer that affects plasma cells in the bone marrow
27
What does acute and chronic refer to?
Acute and chronic refers to how quick the onset of disease sets into patients
28
What does lymphocytic or myeloid refer to?
They refer to the lineage of cancer
29
What are high grade tumours?
They are more progressive versions of the disease and they are undifferentiated and highly abnormal
30
How are many cancer tumours classified?
Many cancers tumours are classified by their stage
31
What does it mean when cancer is classified by Grade?
Grade describes tumours by their cell dfferentiation
32
What are tumours split into?
Into low grade tumours or high grade tumours
33
What are low grade tumours?
They are well differentiated and they closely resemble normal specialized cells.
34
What are the 4 Grades of cancer?
1. Well differentiated cells with slight abnormality
2. Cells are moderately differentiated and slightly more abnormal
3. Cells are poorly differentiated and very abnormal
4. Cells are immature and primitive and undifferentiated
35
What does it mean to classify cancer by stage?
This describes cancer by the extent or severity of it
36
What does classification by stage involve?
It involves TNM staging where T stands for tumour size, N stands for the degree of regional spread or node involvement and M stands for distant metastasis
37
What are the different TNMs and what do they mean?
T0 - no evidence of tumours
T1-4: increasing tumour size and involvement
N0 - No nodal involvement
N1-4: Increasing degrees of lymph node involvement
M0- no evidence of distant tumours
M1-4: evidence of distant spread of tumour
38
What does ALL stand for and discuss it?
ALL stands for acute lymphoblastic leukaemia
Treatments are very effective and 90% of patients will be cured from the disease
39
What does FL stand for and discuss it?
FL stands for Follicular Lymphoma
Patients might die with disease rather than from the disease, however it may transform into a more aggressive form of the disease. They will look like pretty normal cells except the lymph nodes which will be packed full
40
How are cancers distinguished from one another ? hint 5
By parameter, clinical, morphology, immunophenotype, and molecular/genetic
41
Explain how ALL is split up into these 5:
Parameter is acute lymphoblastic leukemia
Clinical shows it is mostly found in children in the bone marrow and blood and that it is aggressive but curable
Morphology shows lymphoid blasts
Immunophenotype is B-lineage progenitors
Molecular/Genetic analysis usually shows no lgH rearrangement and translocations seen mainly at chromosomes at 12/21
42
Explain how FL is split into these 5:
Parameter is Follicular Lymphoma
Clinical analysis shows FL mainly in older patients, observed at lymph nodes. It is indolent but incurable and it may transform into more aggressive disease
Morphology shows follicle centre cells
Immunophenotype shows mature B cells
Molecular/genetic analysis shows cloncal lgH rearrangement with somatic lg mutations and translocations observed at chromosomes 14 and 18
43
What are the causes of cancer?
Cancer is a genetic disease caused by mutations, chromosomal abnormalities and epigenetic effects which effect genes that cause control growth, cell division and cell death
Cancer is caused by external and internal factors
44
Are cancers preventable?
Over 50% of cancers are potentially preventable
45
What are external factors causing cancer?
Tobacco, chemicals, radiation, infectious organisms, etc
46
What are internal factors causing cancer?
Inherited mutations, hormones, immune conditions, etc.
47
What is the number 1 risk factor?
Age - 78% of all newly diagnosed cancer cases in developed countries happens at ages 55 or greater
48
What are the risk factors? Hint 11
1. Age
2. Exposure to carcinogens
3. Alcohol
4. Chronic inflammation
5. Diet
6. Immunosuppression
7. Infectious agents
8. Obesity
9. Radiation
10. Sunlight
11. Tobacco
49
What are the risk factors for breast cancer? Hint 8
1. Age
2. Presence of a substantial family of breast cancer
3. Mutations in breast cancer susceptibility genes: BRCA1+BRCA2 account for 5-10% of all breast cancer
4. Long menstrual history
5. Never having children
6. Recent use of oral contraceptives
7. Having one's first child after age 30
8. Obesity after menopause
50
What percent of breast cancer is caused by BRCA mutations?
5-10% of breast cancer is caused by these mutations
51
Are there other cancer susceptible genes, or is it only from BRCA mutations?
There are other cancer susceptible genes it is not all these BRCA mutations
52
What are BRCA genes?
They are unrelated tumour suppressor genes. They are involved in DNA repair of double stranded breaks, so they are genes which function allows them to stop cellular change to cancer, so they are involved in DNA repair.
53
What is the issue with BRCA mutations in relation to cancer?
Cancer is a genetic disease and anything that affects the repair of double stranded breaks will increase changes of developing cancer.
54
What do inherited mutations in BRCA1+2 predispose someone to?
Inherited mutations in BRCA1+2 predispose to high risks of breast and ovarian cancer
55
What are lifetime risks of breast cancer with BRCA mutations?
They can be as high as 80%.
56
What are lifetime risks of ovarian cancer with BRCA mutations?
Lifetime risks of ovarian cancer are greater than 40% for carriers of the BRCA1 mutation and greater than 20% for carriers of the BRCA2 mutation
57
What percent of ovarian cancer are due to inherited mutations in BRCA1+2?
10-15% of ovarian cancer cases are due to inherited mutations in BRCA1+2
58
What is another inherited mutation that influences risk of breast cancer?
ATM, BARD1, etc.
59
What are the risk factors for prostate cancer?
Age, race, family history
60
What are the risk factors of colorectal cancer?
Age, history of chronic inflammatory bowel disease, obesity, diet high in red and processed meat, smoking, heavy alcohol consumption
61
What are the risk factors of stomach cancer?
50% of new cases due to H. pylori infection, smoking
62
What are the risk factors of lung cancer?
80% of cases in men and 50% in woman worldwide due to smoking
63
What are the risk factors of liver cancer?
Strongly associated with chronic hepatitis B and C infection (>50%)
64
Who has a higher rate of prostate cancer in the US, White/African American/Asian men?
African America in US have higher rate of prostate cancer when compared to white and Asian men
65
What can decrease the incidence of colorectal cancer?
Decreasing alcohol and wine consumption can decrease the incidence of colorectal cancer
66
What is the number one risk factor for lung cancer?
Smoking
67
What percent of lung cancer is due to smoking in men and women?
80% in men and 50% in women of lung cancer worldwide is due to smoking and the incidence of women is increasing each year
68
What type of process is cellular transformation?
Cellular transformation is a multistage process
69
How do we get cancer? Using Blood Cancer is an example
Acute myeloid leukaemia:
- Normal blood cells which are stem cells in bone marrow or progenitor cells down by stem cells in differentiating cascade leading to myeloid cells.
Cells undergo a genetic event and in lots of cases this can be a gross genetic event such as a chromosomal translocation when you get a major defect in chromosomes
- 1st genetic deficit but can also be other ones and this causes other cells to accumulate inside here, and this altered genotype and can give rise to pre-leukaemic state of cells
- This first hit gives pre cancer cell some sort of survival advantage so it can grow and accumulate
- Second hit then happens, and this may be genetic mutations, aberrant microenvironment signals or epigenetic mutations such as methylation in gene promoters.
- Can give rise then to acute myeloid leukaemia a
70
What is found in most cancer cells, is it all the same type of cell?
You find a ponderance of many cells, not just one type of cancer cell is found
71
Can the microenvironment influence the development of cancer?
Yes the microenvironment can influence development of cancer
72
How many mutations take place every day in the body?
70,000 per cell per day, mutations and DNA damage are common
73
What are most of mutations?
Most mutations are repaired
74
What do deleterious mutations lead to?
Deleterious mutations usually lead to cell death
75
What can happen to some mutations?
Some mutations persist and can lead to cancer and these can be called driver mutations such as oncogenes and tumour suppressor genes.
76
What is the other type of mutation called?
The other type of mutations are passenger mutations
77
What are passenger mutations?
They are mutations which have no direct effect on cellular transformation, they can be silent or have a non-essential role in supporting transformation.
78
What can proto-oncogenes do?
Proto-oncogenes perform physiological functions that are necessary for normal cellular homeostasis, such as processes of growth, proliferation, and survival
79
What happens to proto-oncogenes during malignant transformation?
During malignant transformation regulation of the activity of proto-oncogenes is circumvented either by mutation or over-expression
80
How many proto-oncogenes when mutated/over-expressed become oncogenes?
More than 200 proto-oncogenes when mutated or over-expressed become oncogenes
81
What are some functions of proto-oncogenes?
Functions of proto-oncogenes include growth factors (PDGF, EGF), GF receptors (EGFR, HER2), signal transduction (RAS, ABL, RAF), transcription factors (MYC, FOS)
82
What is the basic function of oncogenes?
Oncogenes promote growth
83
What is another name for tumour suppressor genes?
Tumour suppressor genes are the opposite to oncogenes, they are anti-oncogenes
84
What is the basic function of anti-oncogenes (TSGs)?
They suppress growth
85
With TSG what is associated with malignancy?
Loss of inactivation associates with malignancy
86
What to TSG and oncogenes work in concert to drive?
TSG and oncogenes work in concert to drive cellular transformation. Mutation and loss work together in cellular transformation into cancer
87
Give some examples of TSGs:
TSG include BRCA1-2, APC, PTEN, TP53, Retinoblastoma
88
How do TSG protect cells from transformation?
TSG protect cells from transformation by, for example controlling abnormal cell proliferation
89
With cellular change from normal cell to a cancerous ones with colorectal cancer an example, what is an early event?
The mutation and loss of tumour suppressor gene: APC is an early event and this causes dysplasia in early adenoma.
90
What is the second step towards colorectal cancer as the disease progresses?
Mutations occur in oncogenes such as KRAS and altered DNA methylation and this gives an intermediate adenoma
91
After mutations in KRAS and altered DNA methylation, what is there a loss in for the 3rd step of colorectal cancer progression?
There is a loss in signal transduction of tumour suppressor genes such as SMAD2/4 associated of progression to late adenoma
92
What is the final step and mutation of in the progression of colorectal cancer?
Finally, mutation and loss of TP53 tumour suppressor gene is associated with sequence of adenoma to carcinoma
