PP 8+9+10 Neoplasia Flashcards
Tumour meaning
Swelling
Palpable bump
Neoplasm meaning
Abnormal growth of cells that persist after initial stimulus is removed
Oncology
Study or tumours + neoplasms
Neoplasia meaning
New, abnormal tissue growth
Is neoplasia reversible or irreversible?
Ireversible
Benign neoplasm meaning
Growth which remains localised + won’t spread
Cancer meaning
Malignant neoplasm
Malignant neoplasm meaning
Abnormal growth of cells that persists after initial stimulus is removed which can spread
Metastasis meaning
Malignant neoplasm which has spread from primary site
Dysplasia meaning
Pre-neoplastic alteration where cells show disordered tissue organisation
Examples of non neoplastic tumours
Abscess
Haematoma
Is dysplasia reversible or irreversible?
Reversible
How is a benign tumour differentiated?
Well differentiated
What does a benign tumour look like in histology?
Well differentiated
Closely resembles parent tissue
Normal nuclear:cytoplasmic ratio
Uniform cells
Few mitoses
What is a primary malignant tumour?
Tumour at original site
Has not spread yet but has potential to
What is a secondary malignant tumour?
Tumour has spread from original site
How is a malignant tumour differentiated?
Well to poorly differentiated
More often poorly
What does a malignant tumour look like in histology?
High nuclear:cytoplasmic ratio
Necrosis?
Irregular outer margin + shape
Pleomorphism
Many mitoses
Anaplastic meaning
Cells with no resemblance to any tissue
Poor differentiation presentation on histology
Increase in nuclear size
Increase in nuclear:cytoplasmic size
Increase in nuclear staining - hyperchromasia
Increase in mitotic figures
Abnormal mitotic fibres - Mercedes logo
Pleomorphism
Pleomorphism meaning
Variation in size + shape of cells + nuclei
What is a description of an abnormal mitotic fibre in poor differentiation histology?
Mercedes logo
Low grade vs high grade tumour
Low grade - well differentiated
High grade - poorly differentiated
Reasons for neoplasia
Carcinogensis
Non-lethal genetic damage
Describe the process of neoplasia
1- accumulated mutations in somatic cells
2- mutations caused by initiators (mutagenic agents)
3- promoters cause cell proliferation
4- clonal expansion of single precursor cells > tumour
5- neoplasm formed by progression
What is a monoclonal growth?
Growth which has originated from a single cell
List some mutagenic agents/initiators
Chemicals - smoking, diet + obesity, alcohol
Infectious agents - HPV
**Radiation **
Inherited mutations
List classes of normal regulatory genes
Growth promoting proto-oncogenes
Growth inhibiting tumour suppressor genes
Genes that regulate apoptosis
Genes involved in DNA repair
What genes are targets of cancer-causing mutations?
Growth promoting proto-oncogenes
Growth inhibiting tumour suppressor genes
Genes that regulate apoptosis
Genes involved in DNA repair
Function of proto-oncogenes
Part of signally pathway which drive proliferation
What does a mutation in proto-oncogenes do?
Proto-oncogene > oncogene > oncoprotein
What type of mutation effect proto-oncogene?
Dominant mutation
Only 1 allele need to be impacted
What happens when proto-oncogenes become mutated?
Favour neoplasm formation
Function of tumour suppressor genes
Stop cell proliferation
What type of mutation effects tumour suppressor genes?
Recessive
Both alleles must be damaged
What happens if there’s a mutation in tumour suppressor genes?
Inactivate them
Failure of growth invitation
Tumour grows
What happens as a result of a mutation in apoptosis regulating genes?
Less cell death
Enhanced survival of cells
What happens as result of a mutation with DNA repair genes?
Impaired ability of cells to recognise + repair non-lethal genetic damage
Cell mutations occur at increased rate
What do benign tumours often end in?
-oma
What do malignant tumours often end in?
-carcioma (epithelial)
-sarcoma (stromal)
Name of benign neoplasm in strafited squamous epithelium
Squamous papilloma
Name of benign neoplasm in transitional epithelium
Transitional cell papilloma
Name of benign neoplasm in glands
Adenoma
Cystadenoma
Name of malignant neoplasm in stratified squamous epithelium
Squamous cell carcinoma
Name of malignant neoplasm in transitional epithelium
Transitional cell carcinoma
Name of malignant neoplasm in glands
Adenocarcinoma
Name of neoplasms in testis
Malignant teratoma
Seminoma
Name of neoplasm in ovary
Benign treatoma (dermis cyst)
Invasion meaning
Breach of basement membrane with progressive infiltration and destruction of surrounding tissues
Describe the process of metastasis
1- neoplasm grows + invades at primary site
2- enters transport system + lodges at secondary site
3- growth at secondary site to form a a new tumour (colonisation)
Haematogenous spread meaning
Spread via blood vessels
Transcoelomic spread meaning
Spread via fluid in body cavities
Transport systems metastases can travel in
Blood vessels
Lympathic vessels
Fluid in body cavities
What does invasion involve?
Altered adhesion
Stromal proteolysis
Motility
What is epithelial to mesenchymal transition?
Cells take on phenotype for like mesenchymal cells than epithelial
What causes epithelial to mesenchymal transition?
Altered adhesion
Stromal proteolysis
Motility
What is the greatest barrier to successful metastasis?
Failed colonisation
What is the size of most malignant cells at secondary site?
Tiny
Undetectable
What happens to most malignant cells at the secondary site?
Die
Failed growth to detectable tumour
What are micrometastases?
Surviving microscopic metastatic deposits that fail to grow into tumours
What determine the site of secondary tumours?
Regional drainage of blood, lymph or coelomic fluid
Where do lymaphtic metastasis predictability drain to?
Lymph nodes
How does breast cancer typically travel to secondary site
Via ipsilateral axillary lymph nodes
Where is transcoelomic spread often to?
Other areas in coelomic space
Adjacent organs
Where do blood borne metastasis often spread to?
Next capillary bed that the malignant cell encounter
How do carcinomas often travel?
Via lymph
How do sarcomas often travel?
Via blood stream
What is the ‘seed + soil’ phenomenon?
When one metastases don’t go to expected location
What is the ‘seed + soil’ phenomenon usually due to ?
Due to interactions between malignant cells + local tumour environment at secondary site
Where does metastatic disease in bone often take place?
Axial skeleton
How does metastases travel to bone?
Haematogenous sread
Symptoms of metastatic disease to bone
Mostly asymptomatic
Mainly pain if symptomatic
What are common neoplasms that spread to bone?
Great
Bronchus
Kidney
Thyroid
Prostate
What type of metastases does prostate neoplasms cause?
Osteosclerotic metastases
What is the most common site of neoplasm spread to bone in women?
Breast
What is the most common site of neoplasm spread to bone in men?
Prostate
What does it mean if a neoplasm is more aggressive?
It will metastasise very early on
What are tumour cells recognised by?
Immune system recognised them as non-self and destroy them
How are immunosuppressive people more at risk of cancer?
Tumours can avoid the immune system via:
- loss or decreased expression of histocompatibility antigens
- expression of certain factors that suppress IS
- failure to produced tumour antigen
What is tumour cell recognition mediated by?
Cell mediated mechanisms
Where do tumour antigens present?
On cell surface of major histocompatibility complex molecules
What are tumour antigens recognised by?
CD8+ cytotoxic T cells
What are local effects of neoplasms?
Direct invasion + destruction of normal tissue
Ulceration > bleeding
Compression of adjacent structures
Blocking tubes + orifices
Increased pressure due to tumour growth
Systemic effects of neoplasia
- ^ tumour burden > parasitic effect on host
-
secreted cytokines - decreased appetite
- weight loss
- malaise
- immuosuppresion
- thrombosis - hormone secretion
What is paraneoplastic syndrome?
When some cancers exert signs + symptoms are hard to explain based in anatomical distribution or hormone production
What can paranoplastic syndrome mimic?
What is the effect of this?
Metastatic disease
Wrong treatment gvien
What are the processes of hypercalcaemia?
1- osteolysis : due to cancer from primary bone lesions or secondary metastases
2- production of calcaemic humoral substances by extraosseous neoplasms
What does syndrome of inappropriate ADH secretion normally occur with?
Small cell lung cancer
Hyponatraemia
Hyponatraemia meaning
Decreased sodium conc
Myositis meaning
Inflammation of muscle
List some miscellaneous effects of neoplasm
Neuropathies
Skin problems
Fever
Clubbing of rings
Myositis
Hyperglycaemia
Carcinogenesis meaning
Causes of cancer
Intrinsic carcinogens
Hereditary e.g. breast cancer
Age
Sex- horomones
Chronic inflammatory disease
Extrinsic carcinogen
External
Behaviour
Environment - chemical
- radiation
- infection
- viruses
Prevention of cancer
Stop smoking - tobacco
Healthy weight - BMI
Healthy balanced diet - ^ fruit + veg
Sun safety
Less alcohol
Exercise
How does obesity increase the chance of cancer?
1- fat cells increase inflammation + make extra hormones and growth factors
2- hormones, GFs + inflammation cause cells to divide more
3- increased chance of cancer cells being made
4- if made, will divide + cause a tumour
How does smoking increase the chance of cancer?
1- cigarettes smoke releases harmful chemicals
2- chemicals enter lungs + effect body
3- chemicals damage DNA
4- other chemicals make it harder for cells to repair damaged DNA
5- DNA damage an cause cancer cells > tumour
What are the main modifiable risk factors for cancer?
Smoking
Obesity
Alcohol
Unhealthy diet
Lack of exercise
What is 2-napthylamine?
- An industrial carcinogen
- Used in dye manufacturing industry
- In cigaretters
What can 2-napthylamine cause?
Malignant neoplasms
Bladder cancer
What did the study of 2-napthylamine show?
- risk of cancer depends on total carcinogen dose
- sometimes there’s organ specificity for carcinogens
- long delay between carcinogen exposure + malignant onset neoplasm
What does chemical carcinogenesis involve?
Initiation + promotion
1- initiator must be given first
2- then second class of carcinogen - promoter
What is a complete carcinogen?
Acts as initiator and promoter
Example of a complete carcinogen
Tobacco
What is the precursor for a carcinogen?
Pro-carcinogen
What converts pro-carcinogen to carcinogen?
Cytochrome P450
How does asbestos cause cancer?
What cancer does it increase the chance of?
1- causes chronic irritation in lungs
2-chronic inflammation
3- more regeneration
4- increased chance of cancer cells
Mesothelioma - cancer of pleura
What type of cancer does Aflatoxin B1 increase the chance of?
Liver cancer
Radiation definition
Any type of energy travelling through space
How can radiation damage DNA?
- directly
- indirectly via free radicals
What causes ionising radiation?
Radon gas
Medical tests e.g. x-rays
How do infections cause cancer?
- directly affect gene that control cell growth
- indirectly by causing cynic issue injury > regeneration- acts as promoter or causes new mutation from DNA replication errors
Example of infection which has a direct effect on causing cancer
Human papilloma virus
Example of infection which has an indirect effect on causing cancer
Hepatitis B + C
Bacteria + parasites
Example of infection which causes reduced immunity
Human immunodeficiency virus
What cancer is HPV associated with?
Cervical carcinoma
How does HPV cause cancer?
Direct carcinogen
Expresses proteins E6+E7 - inhibit p53 - prevents cells from apoptosing
1- virus infects cell + ensures it doesn’t die
2- hijacks DNA replication machinery (interferes with Retinoblastoma protein
3- more viruses made
What type of gene is the retinoblastoma gene?
Tumour suppressor gene
Function of retinoblastoma gene
- negative regulator or G1/S cell cycle checkpoint
- controls cellular differentiation
What does inactivation/mutation of the retinoblastoma gene cause?
Uncontrolled cell division
What does retinoblastoma gene germ line mutation cause?
Familial retinoblastoma
What is the two hit hypothesis?
1- person with a germ line mutation of TSG on 1 chromosome is more likely to develop a neoplasms
- 1st hit is inherited mutation, only 2nd hit needed
2- person with no germ line mutation - less of a chance of tumour growth - need both hits
Function of P35 gene
- repairs damage in S phase
- causes apoptosis if damage is to extensive
What do inherited mutation in p35 gene cause?
Li-Fraumeni Syndrome
How does Helicobacter pylori cause cancer?
- Causes chronic gastric inflammation + parasitic flukes
- Which causes inflammation in bile duct + bladder mucosa
- Increases risk for gastric + bladder carcinomas
Why do tumour suppressor genes need two hits?
Both alleles must be inactivated
Why do proto-oncogenes need one hit to be activated?
Only be allele needs to be inactivated
What genes inhibit neoplastic growth?
Tumour suppressor genes
What was the first human oncogene to be discovered?
RAS gene
What type of gene is the RAS gene?
Oncogene
Function of RAS gene
Codes for G protein which signals for cells to pass restriction point in cell cycle
What does a mutation in RAS gene cause?
Constant activation of gene
Constant divisions as cells pass restriction point
What type of condition is Xeroderma Pigmentosa?
Autosomal recessive
What is Xeroderma pigmentosa due to?
Mutation in genes which affect DNA nucleotide excision repair
Why are people with Xeroderma pigmentosa more likely to develop skin cancer at a young age?
Sensitive to UV damage
Reduced ability to repair UV damage
What type of disease is Hereditary Non-Polyposis Colon Cancer Syndrome?
Autosomal dominant
What causes Hereditary Non-Polyposis Colon Cancer Syndrome?
Germ line mutation affects DNA mismatch repair genes
What causes familial breast carcinomas?
Mutation in BRCA1+BRCA2 genes
Function of BRCA1+BRCA2 genes
Help to repair double strand DNA breaks
What is a caretaker gene?
Gene that maintains stability
Class of TSG
What are the 6 hallmarks of cancer?
- self sufficiency in growth signals - no longer need GFs for cancer to grow
- resistance to growth stop signals - TSG can’t stop cancer growing
- cell immortalisation
- sustained ability to start angiogenesis
- apoptosis resistance
- ability to invade + produce metastases
What is cell immortalisation?
No limitation of the number of times a cell can divide
What can proto-oncogenes encode?
- growth factors
- growth factor receptors e.g. RAS
- plasma membrane signal trsnducers
- intracellular kinases e.g. BRAF
- transcription factor
- cell cycle regulators
What does TNM stand for?
Tumour size at primary site 0-3
Node involvement 0-2
Metastatic spread in blood 0-1
What are the four most common cancers worldwide?
Lung
Female breat
Bowel
Prostate
Stages of TNM staging system
Stage 1 - early local disease
Stage 2 - advanced local disease N0, M0
Stage 3 - regional metastasis N1, M0
Stage 4 - advanced disease with distant metastasis M1
What is TNM stage 1?
Early local disease
What is TNM stage 2?
Advanced local disease
N0, M0
What is TNM stage 3?
Regional metastasis
N1, M0
What is TNM stage 4?
Advanced disease with distant metastasis
M1
What does grading of neoplasm describe?
The degree of differentiation of a neoplasm
Explain the stages of grading neoplasms
G1 - well differentiated
G2 - moderately differentiated
G3 - poorly differentiated
G4 - undifferentiated or anaplastic
What grade is the best differentiated?
G1
What grade is the worst differentiated?
G4
Treatments of cancer
Surgery
Radiotherapy
Chemotherapy
Horomone therapy
Immunotherapy
Treatments targeted to specific molecular alterations
What is adjuvant treatment?
Treatment is given after surgical removal of a primary tumour to eliminate sub clinical disease
What is neoadjuvant treatment?
Treatment is given prior to surgical excision to reduce the size of the primary tumour
What are the most common cancers in children younger than 14?
Leukaemia
Central nervous system tumour
Lymphomas
The majority of cancers are diagnosed in what age group?
Over 65 years old
Explain radiation therapy
- Kills proliferating cells by triggers apoptosis or interfering with mitosis
- This kills rapidly dividing cells in G2 of cell cycle
- Causes direct or free-radical induced DNA damage - detected at checkpoints of cell cycle
- Double stranded DNA breakages causes damaged chromosomes that prevent M phase from completing correctly
Dose of radiation therapy
Why?
Fractionated doses
To minimise normal tissue damage
Types of radiation therapy
External bean radiotherapy
Internal radiation therapy
Explain external bean radiotherapy
External machine aims radiation of cancer
Explain internal radiation therapy
- Source of radiation put into body
- Brachytherapy (local) - seeds, ribbons or a capsules are placed in or near tumour
- Systemic - radioactive iodine or I-131
Explain brachytherapy
Type of internal radiation therapy
Seeds, ribbons or capsules are placed in or near the tumour
Local
What can be used to treat some thyroid cancers?
Radioactive iodine
What can radioactive iodeine be used to treat?
Some types of thyroid cancer
Explain chemotherapy
- Systemic treatment
- Kills cancer cells that have spread to other parts of body
- Used in isolation or in conjunction with other chemotherapeutic agents
- Often used together with other cancer treatments
Effects of chemotherapy
Hair loss
Mouth sores
Pain
Trouble breathing
Immunosuppressed
Nausea + vomiting
Constipation or diarrhoea
Bruising + bleeding
Neuropathy
Rashes
Types of chemotherapy
Antimetabolites
Antibiotics
Plant derived drugs
Alkylating + platinum based drugs
How does antimetabolites work?
What type of treatment is it?
Example
Mimic normal substrates involved in DNA replication
Chemotherapy
e.g. fluorouracil
How do alkylating + platinum based drugs work?
What type of treatment is it?
Example
Prevent the cross link the two strands of DNA helix
Chemotherapy
e.g. crisplatin + cyclophosphamide
What is rumour grade determined by?
Degree of differentiation
Appearance of nuclei
Presence of mitoses
What is remission of cancer?
Partial or complete
Partial - all signs + symptoms of cancer have reduced
Complete - all signs + symptoms have disappeared
When is cancer most likely to come back after treatment?
Within 5 years
How do antibiotics work to treat cancer?
What type of treatment is it?
Example
doxorubicin inhibits DMA to poison erase needed for DNA synthesis
bleomycin causes double stranded DNA breaks
Chemotherapy
How do plant based drugs work to treat cancer?
What type of treatment is it?
Example
Block microtubules assemble + interfere with mitotic spindle formation
Chemotherapy
vincristine
What does TNM stage 4 cancer normally mean?
Metastasis involved
Explain biomarker testing
Process to look for genes, proteins, bio markers etc.
Therapies selected based on gene profiling
Explain hormone therapy of cancer
Selective oestrogen receptor modulators
ramioxifen binds to oestrogen receptors and prevents oestrogen from binding - to treat hormone receptor positive breast cancer
What is tamoxifen used for?
To treat hormone receptor positive breast cancer
Binds to oestrogen receptors and prevents oestrogen from binding
What is Dukes staging system used for?
Bowel cancer
What is Ann Arbor staging system used for?
Lymphomas
Explain immunotherapy
- Target immune system to help it fight cancer by recognising and attacking cancer cells
- Detects and destroys abnormal cells
What do tumour infiltrating lymphocytes indicate?
The immune system is responding to the tumour
What is a sign that the immune system is responding to the tumour?
Tumour infiltrating lymphocytes
Types of immunotherapy
Immune checkpoint inhibitors
T-cell transfer therapy
Monoclonal antibodies
Treatment vaccine
Immune stem modulators
How do immune checkpoint inhibitors work?
What type of treatment is it?
Block immune checkpoints
Allow immune cells to respond more strongly
Immunotherapy
How does T cell transfer therapy work?
What type of treatment is it?
Boosts the natural ability of T cells to fight cancer
Immunotherapy
How do monoclonal antibodies work?
What type of treatment is it?
Immune system proteins that bind to specific targets on cancer cells
Immunotherapy
How do treatment vaccines work?
What type of treatment is it?
Boost the immune response against cancer cells - strengths natural immune system
Immunotherapy
Importance of tumour markers
Measured for diagnosis
Asses response to therapy
Assess recurrence
Monitoring tumour burden during treatment
Who is cancer screening meant for?
Healthy people with no symptoms
Purpose of cancer screening
Attempts to detect cancer as early as possible
Benefits of cancer screening
- Can detect problems early
- Treatment is more effective the earlier it’s done
- Can reduce the chance of developing complications
- Reduce deaths
- Allow patient to make better informed decisions about general health e.g. no smoking
Risks of cancer screening
- Not 100% accurate
- False positives + negatives
- Even with a negative result person could still develop cancer later on
- Anxiety associated with knowledge of health issue
Results of cancer screening
Normal result - negative
High risk result - positive
What does a normal result to cancer screening mean?
At low risk of having cancer
Doesn’t mean that you will never develop it in the future
What does a high risk result to cancer screening mean?
May have cancer
Offered further tests to confirm
What does sensitivity of screening mean?
The ability of the screening test to identify people with the condition as positive
What does specificity of screening mean?
The ability of the screening programme to identify health people as negative
What makes a good screening programme?
- disease must constitute a significant public health issue
- readily available treatment must be available
- detected at stage where treatment is more effective than if developed
- can detect high proportion of disease in its preclinical state
- safe
- reasonable in cost
- improves health outcomes due to early detection
- widely available
What can blood spot tests on newborn babies be used to screen for?
Sickle cell disease
Cystic fibrosis
Congential hypothyroidism
Phenylketonuria
Homocystinuria
Severe combined immunodeficiency
Explain cervical screening programme?
Smear test
All women 25-64
Cells are taken from cervix
Check for high risk HPV
Future developments for screening
Self sampling
Extending recall intervals
How long after exposure to asbestos does malignant mesothelioma usually occur?
20–40 years
How does asbestos cause cancer?
- Is a complete carcinogen - promoter + initiators > forms free radicals
- Fibres cause chronic irritation in lungs > chronic inflammation > increased repair > increased chance of cancer cell
Staging system for lymphomas
Ann Arbor staging system
What can teratomas contain?
Hair
Teeth
Bones
Muscle
What tumours can contain hair and teeth?
Teratomas
What type of cancer in most common in young people’s testis + ovaries?
Germ cell tumours
What is the common germ cell tumour in testis?
Seminoma
Examples of non-seminoma tumours
Teratoma
Yolk sac tumour
Embryonal
Chriocarcinoma
Tumour markers in testicular cancer
hCG
AFP
What is tumour marker alpha fetoprotein raised in?
Hepatocellular carcinoma - liver
Yolk sac - testi or ovaries
Types of tumours in testis
Seminoma
Non Seminoma - malignant teratoma
- yolk sac tumour
- embryonal
- choriocarcinoma
Properties of a Seminoma
Negative tumour markers
No basement membrane
Many lymphocytes
No tumour markers in testis is indicative of what?
Seminoma
Hodgkin’s lymphoma
Fever
Night sweats
Weight loss
Histological presentation of Hodgkin’s lymphoma
Eosinophil
Reid sternburg cells
Grading system name for breast cancer
Bloom Richardson Easton system
Major side effect of tamoxifen
Agonist for oestrogen receptors in endometrium
Increased risk of endometrial carcinoma
Menopausal symptoms
Increased risk of DVT and pulmonary embolism
How does tamoxifen work?
Antagonist of oestrogen receptors in breast
Agonist of oestrogen receptors in endometrium
What drugs can be used against HER2 positive tumours? (Breast cancers)
Herceptin
What ages are women screen for breast cancer?
How often ?
47-73 years old
Every 3 years
How are women screened for breast cancer?
Mammogram
Are BRCA1+2 proto-oncogenes or TSG?
Tumour suppressor genes
What cancers are associated with BRCA1+2 genes?
Breast
Ovaries
Fallopian tube
Prostate
What is a triple negative breast cancer?
What does this mean for treatment?
HER2 negative
ER negative
GR negative
Limited treatment
Who do we screen for bowel cancer?
Anybody with a bowel
60-74
How do sarcomas commonly metastasise?
Via blood stream
How do carcinomas tend to metastasise?
Via lymphatics