Neoplastic growth Flashcards
1
Q
What is neoplasia?
A
Neoplasia = Greek for “new” (neo) “growth” (plasia)
2
Q
Define neoplasm.
A
Neoplasm = mass of new cells, also known as a tumour
3
Q
What does oncology study?
A
Oncology = study of neoplasms, which may be benign or malignant
4
Q
What is the common term for malignant tumours?
A
Cancer
5
Q
Describe cancer.
A
Cancer is a heterogeneous and multifactorial disease with uncontrolled cell growth and proliferation
6
Q
What is the result of cancerous growth?
A
Rapid increase in tissue mass in the affected parts of the body
7
Q
What is a pre-cancerous lesion?
A
Morphologically altered tissue where cancer is more likely to occur than in normal tissue
8
Q
Give an example of a pre-cancerous lesion.
A
Barrett’s oesophagus
9
Q
What is a pre-malignant condition?
A
A generalized state associated with a significantly increased risk of cancer
10
Q
List examples of pre-malignant conditions.
A
- Oral carcinoma from leukoplakia
- Melanoma from changing skin moles
- Colorectal carcinoma from polyposis
11
Q
What is the global cancer mortality rate?
A
Accounts for 9.3 million deaths per year, projected to increase to 16.5 million
12
Q
What percentage of people will get cancer at some point in their lives?
A
47%
13
Q
How many new cancer cases are there annually in the UK?
A
Around 370,000 new cases
14
Q
What is the predicted survival rate for cancer patients in England and Wales?
A
Half of patients are predicted to survive at least ten years
15
Q
What are general risk factors for cancer?
A
- Age
- Diet (e.g., processed foods)
- Obesity
- Genetic predisposition
- Inherited neoplastic conditions (e.g., BRCA)
- Defective DNA repair syndromes
- Chronic inflammatory conditions
16
Q
List modifiable habits contributing to cancer diagnoses.
A
- UV radiation exposure (3.2%)
- Smoking (20.3%)
- Alcohol (2.4%)
- Diet (5.0%)
- Obesity (5.0%)
- Lack of exercise (0.8%)
- Hormone use (0.4%)
- Infections (5.0%)
17
Q
What characterizes benign tumours?
A
Slow exophytic growth, resemble parent tissue, non-invasive, localized
18
Q
What are the clinical problems caused by benign tumours?
A
- Pressure on neighboring tissues or nerves
- Obstruction of fluid flows
- Production of active hormones/cytokines
- Potential malignant transformation
19
Q
What characterizes malignant tumours?
A
Rapid invasive growth, variable resemblance to original histology, ability to metastasize
20
Q
List features that differentiate benign from malignant tumours.
A
- Growth rate: Slow (benign) vs. Rapid (malignant)
- Mitotic activity: Low (benign) vs. High (malignant)
- Histological similarity: Good (benign) vs. Variable to poor (malignant)
- Invasion: No (benign) vs. Yes (malignant)
- Metastasis: No (benign) vs. Frequently (malignant)
- Border: Encapsulated (benign) vs. Poorly defined/irregular (malignant)
- Necrosis: Rarely (benign) vs. Common (malignant)
- Ulceration: Rarely (benign) vs. Common (malignant)
- Direction of growth: Exophytic (benign) vs. Endophytic (malignant)
21
Q
What are the two components of tumours?
A
- Neoplastic cells (parenchyma)
- Supportive connective tissue and blood vessels (stroma)
22
Q
What is stroma made of?
A
- Fibroblasts
- Myofibroblasts
- Extracellular matrix (ECM)
23
Q
What is the role of myofibroblasts in tumours?
A
Responsible for ‘puckering’ of local tissues and providing mechanical support
24
Q
What are the hallmarks of cancer cells?
A
- Genomic instability
- Self-sufficiency of growth stimulators
- Insensitivity to growth inhibitors
- Limitless replication potential
- Evasion of apoptosis
- Evasion of the immune system
- Sustained angiogenesis
- Ability to invade and spread (metastasis)
25
What are proto-oncogenes?
Normal genes involved in positive regulation of the cell cycle
26
What are oncogenes?
Mutated proto-oncogenes that lead to unregulated cellular growth
27
What are tumour suppression genes (TSGs)?
Genes that inhibit cell proliferation and tumour development
28
What happens to TSGs in cancer?
TSGs lose expression or become inactivated, removing negative regulators of cell proliferation
29
What are the principal targets for genetic damage leading to cancer?
* Growth genes (proto-oncogenes and TSGs)
* Assistance genes (apoptosis-regulating and DNA-repair genes)
30
What is the process of carcinogenesis?
A 4-step pathway: Mutation, Growth & differentiation, Local invasion, Spread (Metastasis)
31
What is the first step in carcinogenesis?
Mutation – change in the target cell
32
What defines the growth fraction in tissues?
The proportion of cells in the proliferative pool
33
How long does it take for a transformed cell to produce a clinically detectable tumour?
90 days (assuming all daughter cells remain in the cycle and no cells are lost)
34
What does differentiation refer to in the context of cancer?
Degree to which neoplastic cells resemble the host tissue
35
What are the two types of differentiation in malignant tumors?
* Well-differentiated
* Poorly-differentiated
36
What is a poor prognostic sign in malignant tumors?
Poor differentiation
37
What characterizes local invasion in cancer?
Malignant cancer cells infiltrate and invade surrounding tissues
38
What is metastasis?
Spread of cancer cells to distant sites in the body
39
Which organs are the most common sites of metastases?
* Lungs
* Liver
* Brain
* Bones
40
True or False: Metastatic cells resemble the cells of the new host tissue.
False
41
What are the routes of metastasis?
* Haematological
* Lymphatic
* Transcoelomic
* Canilicular
42
What is cancer cachexia?
Advanced syndrome of loss of body fat and lean body mass, leading to weakness and anorexia
43
What factors determine cancer prognosis?
* Tumor cell characteristics
* Treatment effectiveness
* Tumor type
* Degree of cellular differentiation
* Extent of tumor spread
44
What is the difference between grading and staging of cancers?
* Grading assesses aggressiveness based on cell appearance
* Staging assesses extent of cancer spread
45
What does the T in the TNM staging system indicate?
Primary tumor dimensions (1-4)
46
What does the N in the TNM staging system indicate?
Lymph node involvement (0-3)
47
What does the M in the TNM staging system indicate?
Distant metastasis (0-1)
48
What are the categories of cancer treatment?
* Surgery
* Radiotherapy
* Chemotherapy
* Hormone therapy
* Immunotherapy
* Targeted therapies
49
What is the purpose of radiotherapy?
To treat disease using high-energy rays, either externally or internally
50
What are common side effects of radiotherapy?
* Nausea
* Epithelial damage
* Infertility
* Fibrosis
* Cognitive decline
* Secondary cancer development
51
What is chemotherapy?
Use of drugs to inhibit or kill proliferating cancer cells
52
What is the fractional cell kill hypothesis?
A given dose of chemotherapy kills a given proportion of cells, not a specific number
53
What are the main compartments of tumor cells?
* Growth fraction (actively dividing cells)
* Resting cells (G0)
* Non-proliferating cells
54
What is the goal of cancer therapy?
* Curative or palliative treatment
* Maximize cell kill with tolerable toxicity
55
What is a major limitation of current cancer therapies?
Targeting cell proliferation rather than lethal properties of neoplastic cells
56
What are some newer approaches to cancer treatment?
* Monoclonal antibodies
* Anticyclins
* Telomerase inhibitors
* Anti-angiogenesis therapies
57
What is the significance of developing combination chemotherapy regimens?
To provide maximal cell kill, prevent resistance, and allow optimal dosing
58
What is the role of immunotherapy in cancer treatment?
Enhancing host immunology to fight cancer
59
What is a key challenge in cancer treatment regarding malignant cell lines?
Total eradication of malignant cell lines not possible using current therapeutic doses.
## Footnote
This highlights the limitations of current cancer therapies in fully eliminating cancer cells.
60
What is the host immune response's limitation in cancer treatment?
Host immune response not adequate to deal with remnant cells.
## Footnote
This indicates that even with treatment, some cancer cells may remain undetected by the immune system.
61
What are some mechanisms of resistance in cancer similar to?
Similar mechanisms to those encountered in antimicrobial Rx.
## Footnote
This suggests that cancer cells can develop resistance in ways akin to bacterial resistance against antibiotics.
62
What are some types of anti-cancer drugs?
* Hormone related compounds
* Hormone analogues
* Hormone antagonists
* Targeted therapy
* Monoclonal antibodies
* Protein kinase inhibitors
* Immunotherapy
* CAR T-cell therapy
* Cancer vaccines
* Immunomodulators
* Antibody-drug conjugates (ADCs)
* Cytotoxic drugs
* Alkylating agents
* Antimetabolites
* Cytotoxic antibiotics
* Antimitotics
## Footnote
This list encompasses various categories of drugs used in cancer treatment.
63
What are classical anti-neoplastic (cytotoxic) drugs primarily designed to do?
Interfere with DNA synthesis or inactivate DNA by disrupting its structure.
## Footnote
This mechanism is critical for the effectiveness of many chemotherapy agents.
64
What is the difference between cell cycle specific agents (CCSA) and cell cycle non-specific agents (CCNSA)?
* CCSA: Work only when cells are in the appropriate place in the cell cycle
* CCNSA: Effective throughout the cell cycle
## Footnote
Understanding these differences is crucial for timing chemotherapy administration.
65
What types of tumors may be hormone-dependent?
Tumours derived from tissues responding to hormones.
## Footnote
This indicates that some cancers may rely on hormonal signals for growth.
66
What treatments are used for hormone-dependent tumors?
* Hormone antagonists
* Other hormones with opposing actions
* Pharmacological antagonists of relevant hormone
## Footnote
These treatments can inhibit the growth of hormone-dependent tumors.
67
What is the role of LHRH agonists in cancer treatment?
Act as physiological antagonists of hormone action or antagonists of hormone synthesis.
## Footnote
LHRH agonists are often used in treating hormone-sensitive cancers.
68
What is the function of monoclonal antibodies in targeted therapy?
Used against HER2 receptors in breast cancer to inhibit cell growth and proliferation signals.
## Footnote
Monoclonal antibodies can also activate proteins that act as cell cycle inhibitors.
69
What is cancer immunotherapy?
Involves using components of the immune system to inhibit the function of proteins expressed by cancer cells.
## Footnote
This is a novel approach that utilizes the body's own defenses to combat cancer.
70
What are cancer vaccines designed to do?
Educate the immune system about what cancer cells 'look like' to recognize and eliminate them.
## Footnote
Cancer vaccines aim to enhance the body's immune response against tumor-specific antigens.
71
What do checkpoint inhibitors do in cancer treatment?
Prevent the 'off' signal from being sent to T-cells, allowing them to kill cancer cells.
## Footnote
This approach enhances the immune response against tumors by blocking inhibitory signals.
72
What is CAR T-cell therapy?
Uses patient’s own immune cells modified to seek out and eliminate cancer cells.
## Footnote
This specialized treatment has shown promise in aggressive forms of cancer.
73
What is an oncolytic virus?
A virus that preferentially infects and kills cancer cells.
## Footnote
Oncolytic viruses can also stimulate immune responses against tumors.
74
True or False: Tumors may appear to grow before shrinking due to inflammation from immune cell infiltration during immunotherapy.
True
## Footnote
This phenomenon is known as pseudoprogression, specific to immunotherapy treatments.
