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Year 2 Medicine Leeds > EMS > Flashcards

EMS Flashcards

1
Q

What is a nucleosome?

A

200 base pairs of double stranded DNA wrapped around a histone core octamer

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2
Q

Describe the mitochondrial genome

A

Circular, cytoplasmic material inherited via oocyte cytoplasm

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3
Q

What its satellite DNA?

A

Large blocks of repetitive sequence heterochromatin, tenderly repeated sequences with possible polymorphic blocks
- alphoid DNA 171bp repeat unit required for centromere assembly

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4
Q

What are interspersed repeats?

A

Alu repeats

  • Scattered around the genome, individual copies at many locations
  • Short interspaced nuclear element
  • Dispersed into retro transposition
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5
Q

What is a de novo mutation?

A

A new mutation which has occurred during gametogenesis - parents are not affected and do not have the mutation in their somatic tissue

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6
Q

What is anticipation?

A

Symptoms of a genetic disorder becoming more severe as the gene is passed on through each generation

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7
Q

What is Mocaicism?

A

A new mutation occurrence post-zygotically

- distribution of mutant cells is unpredictable and could involve lethal mutations if non-mosaic

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8
Q

Describe Sanger sequencing

A
  • Use PCR as a template DNA in the reaction
  • Template DNA, nucleotides and polymerase to reaction (+primer)
  • Add dye terminator nucleotides (ddNTPs) to terminate the sequence reaction labelled with fluorescent dyes
  • cycle through denaturing, annealing and extension 35 times
  • DNA will be different lengths due to random incorporation of terminator bases and separate as they leave the capillary based on their size
  • Excited with a laser and each dye gives off a different signal which can be collected and decoded
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9
Q

Describe next generation sequencing

A
  • Clonal sequencing machines which sheer the DNA wanted and make small clones using PCR onto a flow cell
  • Similar to Sanger
  • Sequencing reads are small (150bp)
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10
Q

Describe whole exome sequencing

A
  • Generate an exam library - sheer genomic DNA, amplify, tag, hybridise it with a library of probes matching axons in the genome
  • have small magnetic bead on the end so we can pull out the sequences that have hybridised
  • Go into standard ilumino ex gen sequencing to produce the sequencing reads
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11
Q

Describe comparative genome Hybridisation (aCGH)

A
  • Standard reference DNA and patient DNA
  • Cut and label with patient DNA green fluorescent dye and reference DNA with red dye
  • Hybridise it to an array - lots of probes and expand genome
  • if equal red and green = yellow
  • can see different quantities of DNA but not where it is in the genome
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12
Q

What is the dosage effect?

A

Copy number variation, CNV - loss usually worse phenotype than gain
Types:
- Aneuploidy, polyploidy
- Chromosome structure - deletion/duplication
- Mosaicism

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13
Q

What is the position effect?

A

Gene in a new chromosomal environment functions inappropriately - unmasking of a recessive disorder

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14
Q

What are the three viable trisomy’s?

A

Trisomy 13 - patau syndrome
- microcephaly, holoprosencephaly, cleating, polydactyly

Trisomy 18 - Edward’s Syndrome
- microcephaly, growth retardation, rocker-bottom feet, clenched hands and cardiac abnormalities

Trisomy 21 - Down’s syndrome
- Aneuploidy, resulting from meiotic errors, strong maternal age effect, little or no paternal effect

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15
Q

Describe Polyploidy

A
  • Errors at fertilisation, most usually triploidy

- Parental origin effect

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16
Q

Describe reciprocal translocation?

A
  • Breaks and exchanges of chromosomes
  • Stem from meiotic errors in segregation and can produced unbalance gametes
  • Pachytene cross
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17
Q

Describe Robertson Translocation

A
  • Whole arm fusion
  • Acrocentrics - short arm loss
  • No phenotype, reproductive risk
  • Full genetic makeup just 45 chromosomes not 46
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18
Q

What are 4 types of normal genetic variations?

A
  1. Single nucleotide polymorphisms
  2. INDEL’s - insertion or deletion of one or more nucleotides
  3. SNP + INDEL’s - target site for nuclease enzymes - restriction fragment length polymorphisms RELPs
  4. CNVs - large indwells change copy number of sequence greater than 100 nucleotides in length
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19
Q

Describe allelic heterogeneity

A

Different pathogenic variants in a single gene leading to multiple different phenotypes

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20
Q

Describe a point mutation

A

Mutation that effects a single nucleotide

- most common cause of disease

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21
Q

Describe variant consequences

A 
Protein effect:
- No effect 
- Exchange for reference amino acid for alternate 
- Null effect - complete absence of the genes protein product 
People Effect:
- No effect 
- Contribution to individual variation 
- Cause of mendelian disease 
- Contribution to normal disease
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22
Q

Describe missense mutation

A
  • DNA change
  • Incorporation of different amino acid at that position substitution
  • effect on protein depends on the degree of difference between the reference and substituted amino acids
  • Conservative - substitution within the same group
  • Non-conservative - amino acid substitution to one in a different group
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23
Q

Describe Null Variants

A
  1. Nonsense
  2. Frameshift
  3. Canonical splice site variants - occur at the boundary of an exon and intron impacting splicing
  4. Loss of start codon
  5. Single exon or multiexon deletion
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24
Q

Describe Atheroma

A

intimal lesion that protrudes into vessel wall
- Raised lesion with soft core of lipid (Mainly cholesterol and cholesterol esters) covered by a fibrous cap
Commonly affected vessels:
Bifurcations, abdominal aorta, coronary arteries, popliteal arteries, carotid arteries, circle of wills

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25
Q

Describe atherosclerosis formation

A

Starts with damage or injury to the inner layer of an artery

  • Development of a chronic inflammatory response of the arterial wall to endothelial injury
  • Lesion progression through interactions of modified lipoproteins, monocyte-derived macrophages, T-lymphocytes and normal cell constituent of artery wall
  • Fatty Streak - earliest lesion in atherosclerosis composed of lipid filled foamy macrophages - begins as multiple flat yellow spots and begin to form in adolescence
  • Intermediate lesion
  • Atheroma
  • Fibroatheroma
  • Complicated lesion
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26
Q

Describe a thrombus

A
  • Solid mass of blood constituents formed within the vascular system in vivo
  • Commonly superimposed on atheroma
  • Venous thrombosis commonly caused by stasis
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27
Q

Describe Virchow’s triad

A

Endothelial Damage
Hypercoagulability - Heredity (Factor V Leiden, prothrombin G2021OA, Protein C and S deficiency) or acquired
Stasis

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28
Q

Describe an embolus

A

A mass of material in the vascular system able to become lodged in the vessel and block its lumen
- Most derived from thrombi

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29
Q

What is ischaemia and Hypoxia?

A

Ischaemia = interruption of blood flow to cells and tissues reducing oxygen supply
Hypoxia - when the oxygen supply to tissues is impaired
ischaemia always results in hypoxia

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30
Q

Describe the mechanisms of ischaemic cell injury

A
  • Decreased oxidative phosphorylation
  • Switch to anaerobic respiration
  • Failure of Na pump
  • Membrane damage and leakage of intracellular proteins - enzymatic digestion of cell
  • Failure of Ca pump
  • Decreased protein synthesis
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31
Q

Describe detection of ischaemic cell injury

A

Increased lactate
Creatine kinase, troponins - cardiac muscle damage
Transaminases, alk phosphate - liver damage

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32
Q

What are the 6 causes of ischaemia?

A
  1. Vascular occlusion
  2. Vasospasm
  3. Vascular Damage
  4. Extrinsic compression
  5. Mechanical interruption
  6. Hypoperfusion
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33
Q

What are the 5 factors for ischaemia outcome dependence?

A
  1. The nature of the blood supply - alternative?
  2. The duration of ischaemia
  3. The rate of vascular occlusion
  4. Tissue vulnerability - brain takes 3-4 mins for irreversible damage, heart takes 20-30mins
  5. The blood oxygen content
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34
Q

Describe necrosis and the two types

A

Coagulative - denaturation, basic outline of cell is preserved but DNA and internal material is lost - eosinophilic ghost cells
Liquifactive - enzyme digestion from inside out

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35
Q

What are the types of shock?

A

Hypovolaemic - haemorrhage and non-haemorrhagic
Cardiogenic - myopathic, arrhythmia related, mechanical, extra-cardiac
Distributive - anaphylactic, septic, TSS, neurogenic
Obstructive

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36
Q

Symptoms of peripheral Arterial Disease

A
  • Hairloss of legs and feet
  • Numbness or weakness in the legs
  • Brittle slow growing toenails
  • Ulcers on feet and legs - non-healing
  • Skin colour changes
  • Shiny skin
  • Painful numb limb
  • Wounds and ulcers
  • Gangrene
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37
Q

What is ischaemic heart disease and its syndromes? (4)

A 
Cardiac muscle dysfunction due to inadequate blood supply to the myocardium 
Syndromes:
Angina pectoris 
Acute coronary syndrome 
Sudden cardiac death 
Chronic ischaemic heart disease
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38
Q

Describe MI gross morphology

A

< 24h - normal
1-2 days - pale, oedematous, myocyte necrosis, neutrophils
3-4 days - yellow with haemorrhage edge, myocyte necrosis, macrophages
1-3 weeks - red-grey to grey-white, pale, thin, granulation tissue then fibrosis
3-6 weeks - dense fibrous scar

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39
Q

Describe NSTEMI (Subendocardial MI)

A
  • Can infarct without any acute coronary occlusion
  • Normally relatively poorly perfused
  • Need for oxygen cannot be met
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40
Q

What are the blood markers for cardiac myocyte damage (Cardiac enzymes) (5)

A

Troponins T&I
- detectable 2-3 hours after, peaks at 12-48 hours - detectable for 7 days post MI
Creatine Kinase MB - 2-3 hours after, peaks 10-24 hours and detectable up to 3 days
Myoglobin - peak at 2 hours and also released from damaged skeletal muscle
Lactate Dehydrogenase Isoenzyme 1 - peaks at 3 days detectable to 14 days
Aspartate Transaminase - also present in liver so less useful for cardiac damage

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41
Q

Describe MI Treatment

A
  • M.O.N.A - Morphine, oxygen, nitrates and aspirin
  • Reperfusion
  • Ace-1, anti platelets and anticoagulation
  • Anti-arrhythmics, beta-blockers
  • Statins
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42
Q

What are some complications of MI?

A
  • Arrhythmias, ventricular fibrillation
  • Sudden death
  • Myocardial rupture
  • Cardiac mural thrombus and emboli
  • Pericarditis
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43
Q

Describe familial hypercholesterolaemia

A
  • Mutation in genes involved in cholesterol metabolism
  • LDL receptor gene
  • Apolipoprotein B
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44
Q

Describe left and right sided heart failure

A

Left - problems with pumping of blood outside the main circulation
Right - problems coming from the central circulation and pumping into the lungs

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45
Q

Describe Alzheimers disease and the two dominant genes

A
  • Familial clustering 3 to 10 relative risk to second sibling
  • Two genes dominant for Alzheimers - PSEN1 and PSEN2
  • 95% multifactorial
  • Most implicated because of heart disease gene APOE which has three alleles
    E2 - protective effect
    E3 - low risk
    E4 - increased risk to 90%
  • Mean age of consent decreases with increased risk from 84 to 68
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46
Q

Describe Linkage disequilibrium

A
  • Most disease bearing chromosomes in populations are descended from a few ancestral chromosomes
  • Can detect association <2-3 cM
  • Careful selection of control groups in GWAS
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47
Q

What are the causes of cell death? (6)

A 
Hypoxia 
Physical agents - temperature, trauma, radiation 
Chemical agents 
Immunologic agents 
Genetic rearrangements 
Nutritional imbalance
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48
Q

What are the types of cell injury?

A

Reversible
- cell swelling, pallor, hydropic change, vacuolar degenerations
Irreversible
- mitochondrial swelling, lysosomes swells, damage to membranes and leakage of enzymes
Ischaemic Reperfusion Injury
- New damage on repercussion mediated by free oxygen radicals

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49
Q

What are the factors determining the outcome of injury?

A
  • Ability of cells to replicate

- Ability to rebuild complicit architectural structures

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50
Q

Describe labile cell populations

A
  • High normal turnover
  • Active stem cell population
  • Excellent regenerative capacity
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51
Q

Describe stable quiescent cell populations

A
  • Low physiological turnover
    Turnover can massively increase if needed
  • Good regenerative capacity
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52
Q

Describe the permanent cell populations

A
  • No physiological turnover
  • long life cells
    No regenerative capacity
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53
Q

Describe organisation of cells (scar formation)

A
  • The repair of specialised tissue by formation if a fibrous scar
  • basic stereotyped pathological process
  • Production of granulation tissue - acting as a scaffold of fibrin and removal of dead tissue by phagocytosis
  • Granulation tissue contracts and accumulates collagen forming a scar - type 1 + 3
  • organisation is a common consequence of pneumonia and infarction
    Organised area = firm and puckered
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54
Q

Describe healing by first and second intention

A 
First 
- Clean surgical wounds 
- Good haemeostasis 
- Edges opposed with sutures or staples
Second 
- Wound edges are not opposed 
- Extensive loss of tissue 
- More florid granulation tissue reaction 
- More extensive scaring
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55
Q

Describe control of healing

A
  • Blood coagulation and platelet degranulation releases growth factors which are chemotactic for macrophages
  • Macrophages migrate into the wound and phagocytose bacteria and necrotic debris
  • Growth factors are also released by platelets and activate basal epidermal cells
  • Growth factor released forms dermal myofibroblastic cells, epidermal cells and saliva
  • Nutrients, oxygen, hormones and growth factors diffuse in from blood supply and contribute to epidermal growth
  • Lack of nutrients, inhibitors factor presence - infection, steroids, or poor blood circulation inhibit wound healing
56
Q

Describe fracture healing

A
  • Haemorrhage around and within the bone
  • Haematoma is organised
  • Removal of necrotic fragments
  • Osteoblasts lay down disorganised woven bone (callus)
  • Remodelling according to mechanical stress
  • Replacement by more orderly lamellar bone
57
Q

Describe healing of the brain

A
  • Neurones are terminally differentiated
  • Supporting tissue is glial cells rather than collagen and fibroblasts which can proliferate
  • Damaged tissue is removed and often leave cyst
  • Gliosis rather than scarring
58
Q

Describe acute inflammation

A
  • Initial response to injury
  • Can last minutes, hours or days
  • Characteristic is cell neutrophil polymorph
59
Q

Describe the physical characteristics of acute inflammation

A

Rubor, calor, tumor, dolor, laesa

60
Q

What are the major components of acute inflammation?

A
  1. Change in vessel calibre
  2. Increased vascular permeability and fluid exudate formation
  3. Cellular exudate formation
61
Q

What is fluid exudate?

A

Extravascular fluid with a high protein concentration containing cellular debris

62
Q

What is a transudate?

A

Low protein, little or no cellular component

63
Q

What is pus?

A

Inflammatory exudate rich in neutrophils dead cell debris and microbes

64
Q

Describe chronic inflammation

A

Inflammation of prolonged duration, concomitant tissue destruction and repair

65
Q

Describe granulation/granulomatous tissue

A
  • Collection of activated epithelioid macrophages
  • Surrounded by mononuclear leukocytes
  • May contain multinucleate giant cells
66
Q

What is the treatment of paracetamol overdose?

A
  • Activated charcoal

- N-acetyl cysteine - L-cysteine Glutathione

67
Q

What is suppuration?

A

Formation of pus in abscess

- usually staphylococcus, streptococcus or gonococcus

68
Q

What are prions?

A

Misfloded protein, no genetic material, can be inherited spread via contaminated material or occur spontaneously

69
Q

What is cell wall of fungi made of?

A

Chitin

70
Q

What is the cycle of infection?

A 
Encounter
Entry
Spread
Evade Defence
Multiply & Damage 
Disperse
71
Q

Describe pneumococcal surface protein A

A
  • Prevent complement mediated killing IgA protease
  • Secretory immunoglobulin A found in mucosal secretions of respiratory and urogential tract
  • Bind to pathogens to prevent them adhering to host tissues
72
Q

What is Pneumolysin?

A
  • Secreted by S.Pneumoniae
  • Multiple monomers come together and bind to cholesterol in host plasma membrane
  • Pore formation, host cell releases internal contents and dies
73
Q

Describe Hyaluronidase & Neuraminidase’s

A
  • Enzyme capable of degrading hyaluronic acid, silica/neuraminic acid
  • Both targets are components of interstitial cement in connective tissue or epithelial cells
74
Q

Describe type 1 hypersensitivity

A
  • IgE antibody mediated mast cell and basophil degranulation
  • Degranulation causes histamine, proteases and chemotactic factors to be released
  • Hayfever, asthma, hives etc
75
Q

Describe type 2 hypersensitivity

A
  • IgG mediated cytotoxic
  • Directed against cell surface antigens mediates cell destruction via complement
  • Blood transfusion reactions
76
Q

Describe type 3 hypersensitivity

A
  • Immune complex mediated
  • IgG/ IgM against soluble antigen immune complex deposition
  • Vasculitis
  • Traditional cause of serum sickness
  • Arthus reaction
77
Q

Describe type 4 hypersensitivity

A
  • Antigen specific T cell mediated cytotoxicity
  • Sensitised Th1 cells release cytokines which activate macrophages or Tc cells which mediate direct cellular damage
  • Contact dermatitis, tubercular lesions and graft rejection
78
Q

What is an ulcer?

A

Local defect or excavation of surface of an organ or tissue that is produced by sloughing of inflammatory necrotic tissue

79
Q

What are the causes of leg ulcers?

A 
Vascular - Venous most common 
Neuropathic 
Inflammatory 
malignant 
Latrogenic 
Infection 
Metabolic 
Traumatic
80
Q

What is lipodermatosclerosis?

A
  • Inflammatory skin condition resulting from underlying venous insufficiency
  • resulting venous hypertension causing increased leukocytes within veins which migrate to surrounding tissues
  • Leukocytes are activated and attract pro inflammatory cells and cytokines inducing a chronic inflammatory state
  • Increased collagen production leading to fibrosis of subcutaneous fat
81
Q

Describe pyoderma gangrenosum

A
  • Inflammatory ulcer

- One of a number of neutrophilic dermatoses

82
Q

Describe pentoxifylline

A

Licensed for venous leg ulcers - 400mg BD-TDS

- Increase microvascular blood flow thereby enhancing oxygenation of ischaemic tissue

83
Q

What is the most allergenic drug in the anaesthetic cupboard?

A

Teicoplanin

84
Q

Describe chlorohexidine anaphylaxis

A
  • Causes 10-15% of all preoperative anaphylaxis
  • Severe IgE mediated reactions
  • Hidden allergen
85
Q

Describe hyperammonaemia in the liver

A
  • Liver unable to perform urea cycle to convert toxic ammonia to urea for excretion in urine
  • Ammonia stimulates the respiratory centre causing hyperventilation and blows off CO2 leading to increased blood pH - respiratory alkalosis
86
Q

Describe mechanisms of disease

A
  1. accumulation of a toxin - hyperammonaemia + porphyrins
  2. energy deficiency
  3. deficient production of essential metabolite/structural component
87
Q

Describe inborn errors of metabolism (IEM) diagnosis

A
  • Pre symptomatic screening
  • Investigations of symptomatic individuals
    Test body fluids for abnormal metabolites
    measure enzyme activity
    Histochemical staining
    DNA analysis
88
Q

What are the 9 disorders screen for in newborns and what is screened for?

A
  1. Congenital Hypothyroidism
  2. Sickle cell and Hb disorders -
  3. CF -
  4. PKU - phenylketonuria
  5. MCADD - medium chain acyl CoA dehydrogenase deficiency - acylcarnitines urine organic acid for confirmation
  6. MSUD - maple syrup urine disease - leucine target for confirmation
  7. IVA - isovaleric acidaemia - carnitine C5 for screening target
  8. Homocystinuria - non-pyridoxine responsiveness -methionine screening target
  9. GA1 - glutaric acuduria type 1 - glut aryl carnitine C5DC for screening target
89
Q

What are porphyrins?

A

Natural chemicals made of proteins - making of haem for haemoglobin

90
Q

What is treatment for hyperkalaemia?

A
  • Correct the acidosis if this is the cause
  • Stop unnecessary supplements/intake
  • Give Glucose and insulin to drive potassium into cells
  • Ion exchange resins
  • Dialysis
91
Q

Describe Base excess

A

Amount of acid or alkali to titrate blood pH to 7.40
Normal = purely respiratory disorder
Negative BE < -2.3 mmol/L - metabolic acidosis
Positive BE > 2.3 mmol/L - metabolic alkalosis

92
Q

What is hyperplasia?

A

Increased number of cells caused by cell division - possible in labile and stable cell populations

93
Q

What is atrophy?

A
  • Reduction in size of organ or tissue by decrease in cell size and number
  • Reduction in volume of individual cells and death of individual cells
94
Q

What is agenesis?

A

Complete failure of organ to develop

95
Q

What is aplasia?

A

Failure to maintain size or function

96
Q

What is dysgenesis?

A

Abnormal organ development

97
Q

What is hypoplasia?

A

Underdevelopment of tissue/ lack of cells

98
Q

What is metaplasia?

A
  • Transformation of one differentiated cell type into another
  • Trans differentiation of stem cells
  • Can affect epithelium and mesenchymal tissue
99
Q

What is dysplasia?

A
  • Earliest morphological manifestation of multistage process of neoplasia
  • In-situ disease - non invasive
  • Shows cytological features of malignancy but no invasion
100
Q

What is anaplasia?

A

A neoplasm that is poorly differentiated and highly pleomorphic

101
Q

What does pleomorphic mean?

A

A high number of cells that show variability in cell size and shape

102
Q

Describe tumour stroma

A

Desmoplastic - stromal cells have different function to normal stoma - tumour stroma has a role in the hallmarks of cancer

103
Q

Describe the effects of primary tumour invasion

A
  • Invasion into and replacement of normal tissues
  • Pressure on normal tissue, invade into blood vessel causing bleeding
  • Growth into lumen causing obstruction
104
Q

Describe the effects of distant tumour metastases

A
  • Cause the same effects as a primary tumour in an alternative place
105
Q

Describe the effects of paraneoplastic syndromes

A
  • Signs and symptoms that are not related to the local effects of the primary or secondary tumours
  • Develop as a result of proteins, hormones and secreted by tumour cells
  • Immune cross reactivity between tumour cells and normal tissues
106
Q

Describe the cancer prefix for: smooth muscle, skeletal muscle, adipose, blood vessel, bone, cartilage and fibrous tissue

A 
Smooth muscle - leiomyo- 
Skeletal muscle - rhabdomyo-
Adipose - lipo- 
Blood vessel - angio-
Bone - osteo- 
Cartilage - chondro- 
Fibrous - fibro-
107
Q

Describe homologous recombination in DNA repair

A
  • Type of genetic recombination where genetic information is exchanged between two similar
  • Used by cells to accurately repair harmful breaks that occur on both strands of DNA
108
Q

Describe non-homologous end joining in DNA Repair

A
  • Repairs double strands and breaks
  • Break hands are directly ligated without the need for a homologous template
  • Non-homologous end joining is the primary repair pathway used by cells when the experience DNA damage
  • Prior to replication in G1 or early S phase this provides rapid but sometimes imprecise way to maintain genomic integrity
  • Preferred repair pathway when cells reach later stages G2 + M phase sister chromatids are used as templates
  • Kinases trigger activation of key gate keeper of genome P53
109
Q

What is the key gate keeper of the genome and what activates it?

A

P53 tumour suppressor activated by kinases

110
Q

What is genomic imprinting?

A
  • Ensures functional non-equivalence of the maternal and paternal genomes
  • Non encoded in the DNA nucleotide sequence
  • Depends on modifications to the genome during gametogenesis
111
Q

What is the transformation zone?

A

The area between original and new SCJ where the columnar epithelium has been and/or is being replaced by new metaplastic squamous epithelium

112
Q

What are the risk factors for cervical intraepithelial neoplasms?

A

Women: HPV, first coitus<17 yrs, multiple sexual partners, long term oral contraception
Men: penile warts, multiple sexual partners, cervical cancer in previous partner

113
Q

What is a colposcopy used for?

A

To diagnose cervical intraepithelial neoplasia and differentiate high grade lesions from low grade abnormalities

114
Q

Describe Paget’s disease in relation to the reproductive system

A
  • 1% of vulval cancers
  • Usually seen in 70 +
  • Pruitus, burning, eczematous patch
  • 30% of patients have synchronous or metachronus internal carcinoma - most common of breast of genitourinary system
115
Q

What is triple assessment of breast lumps and describe each stage?

A 
Clinical, Imaging and Pathology 
Clinical:
- Mobile or fixed
- Well defined or not 
- Smooth or irregular 
- Firmness 
- Location 
- Nipple inversion/rash/discharge 
- Tethering/retraction
- Oedema 
- Ulceration/fungating lesion

Imaging:

  • Ultrasound
  • Fat - hypoechoic white
  • Fibroglandular breast tissue - echogenic black
  • Identify lesions: size, solid or fluid filled
  • Mammogram

Pathology:

  • Core biopsy
  • Pathological examination
  • Tissue embedded in wax before being cut ready for examination
  • Cytology - fine needle aspiration to show some of the cells
116
Q

Describe acquisition of motility and loss of adhesion

A
  • Cell to cell adhesion molecule - cadherins, mutation causes reduced cell-cell adhesion
  • Cell matrix adhesion molecule interns, mutation causes expression changes leading to decreases cell-matrix adhesion
117
Q

Describe proteolytic enzymes

A
  • Most important enzyme in neoplastic invasion is matrix metalloproteinases
  • Secreted by malignant neoplastic cells
  • Can digest 3 surrounding major connective tissue types
    1. Interstitial collagenases - degrade type 1,2,3 collagen
    2. Gelatinases degrade type 4 collagen and gelatin
    3. Stromelysins degrade type 4 collagen and proteoglycans
118
Q

Describe tumour stage

A 
T- extent of tumour spread 
T0 - no evidence of primary tumour 
T1-T4 - increasing size/invasion of tumour 
N - extent of nodal spread 
N0 - no regional node metastases 
N1-N3 - increasing involvement of nodes 
M - presence or absence of distant metastases 
M0 - no distant metastases 
M1 - distant metastases
119
Q

Describe tumour grade

A

How aggressive a tumour is
1. how much do the cancer cells resemble the normal tissue- differentiation
Well differentiated - low grade
Poorly differentiated - high grade
2. The variation in size and shape of the cancer cells - pleomorphisms
3. How many cells are actively dividing, can count mitotic figures - proliferation

120
Q

Describe the evasion of growth suppressors in carcinogenesis

A
  • Rb protein is key regulator of cell cycle by preventing progression from G1 to S phase
  • Negative GFs inhibit progression of cell cycle by activating Rb protein
  • Inactivation of Rb gene is common event in tumours and results in resistance to negative growth regulation
121
Q

Describe avoiding of immune destruction in carcinogenesis

A

Binding of PD-1 and PD-L1 inhibit T cell from killing tumour cell

122
Q

Describe enabling of replicative immortality in carcinogenesis

A
  • Telomeres shrink with each cell cycle
  • Telomere shortening in cancers does not follow the path its meant to so cells replicate for a much longer time that they usually would
123
Q

What are the 9 hallmarks of carcinogenesis?

A
  1. Sustaining proliferative signalling
  2. Evading of growth suppressors
  3. Avoiding immune destruction
  4. Enabling of replicative immorality
  5. Tumour Promoting inflammation
  6. Activating invasion and metastasis
  7. Inducing of angiogenesis
  8. Resisting cell death
  9. Deregulated metabolism
124
Q

Describe proto-oncogenes

A

Normal genes that promote cell proliferation, survival and angiogenesis

  • Encode for protein directly
  • Involved in control of cell proliferation
  • Allow for checkpoints to be overcome - Ras, myc
  • Dominant
125
Q

Describe oncogenes

A

Mutated versions/increased expression of proto-oncogenes causing increased/uncontrolled activity of expressed proteins

126
Q

Describe 5 tumour suppressor genes

A 
Act to maintain checkpoints, control genome stability 
P53
Rb 
APC
BRACA1/2
hMLH1/hMSH2
127
Q

What are the typical investigations for a suspected ovarian tumour?

A
  1. Refer urgently to gynaecology
  2. Baseline bloods including LFTs
  3. Serum CA125 tumour marker in ovarian cancer
  4. Pelvic and abdominal ultrasound
  5. CT pelvis and abdomen to confirm previous tests
128
Q

Describe epithelial ovarian cancer and its symptoms

A
  • Responsible for more deaths than any other gynaecological malignancy in the UK
  • Presents late
    Non-specific symptoms
  • Weight loss
  • Bloating
  • Fatigue
  • Urinary frequency increase
  • PV bleeding
129
Q

Describe teratomas

A
  • Most common germ cell tumour
  • Nearly all are benign
  • Arise from oocyte once they have completed the first mitotic division
  • Tumour that contains elements of all three germ cell layers
130
Q

What is a dysgerminoma tumour and what can be used as a tumour marker?

A

Germ Cell tumour
Malignant, very rare
- LDH used as tumour marker, sensitive to chemotherapy

131
Q

What is a yolk sac tumour and what can be used as a tumour marker?

A

Germ cell tumour
Malignant
- sensitive to chemotherapy
- Alpha-Feto protein used as tumour marker

132
Q

What is a choriocarcinoma tumour?

A

Germ cell tumour Extremely rare and malignant
- Differentiation towards placenta
produces betaHCG as tumour marker

133
Q

Describe sex cord stromal tumours

A
  1. Thecoma/fibrothecoma/fibroma
    - Benign
    - Thecoma and fibrothecomas produce estradiol
  2. Granulose cell Tumours
    - Low grade malignant tumour producing estradiol
  3. Sertoli Leydig cell tumours
    - Produces androgens - 10-25% malignant
134
Q

What is Meig’s Syndrome?

A

Triad of ovarian tumour (fibroma) right sided pleural effusion and ascites

135
Q

Describe BRAF inhibitors

A
  • 50% of melanomas have somatic mutation in the BRAF gene

- New target therapy vemurafenib recently showed a 48% response rate compared with 5% for standard chemotherapy

Year 2 Medicine Leeds (4 decks)

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