IBSc: Question 3 By Alan McLeod Tested by Natalie Hayes.
-
Upload
sherman-park -
Category
Documents
-
view
222 -
download
2
Transcript of IBSc: Question 3 By Alan McLeod Tested by Natalie Hayes.
Getting the best marks
Read the whole question – a latter section may give you a
clue about an earlier one.
To see how many points you need look at the marks
allocated – for example a 3 point question is generally looking for 3 salient points
If giving a list answer put the best answers first – examiners will not usually mark answers too
far down a list
Always write something – it may get you part of a mark and is anonymised so
no one will think you are stupid!
If you genuinely have no clue then re-write the question to see if this sparks
some ideas.
If not then move on and come back at the end. And remember – always
write something.
Good luck!
Question 4
Mr Jackson, a 62 year old retired bricklayer has
been experiencing haemoptysis for
three weeks.
Q4.1• List 4 differentials for
haemoptysis (4)
Question 4
Cigarette smoke is a known carcinogen.
Q4.3• List two other
carcinogens (1)
Q4.4• What are the three
stages of carcinogenesis (3)
Question 4
You suspect lung cancer.
Q4.5• What additional
symptoms might you ask about to support your hypothesis (2)
Q4.6• What cancer specific
tests might you order (3)
Question 4
Tests reveal a squamous cell
carcinoma of the lung with liver metastases.
Q4.7• Aside from SCC, list two
other common types of lung cancer (2)
Q4.8• What changes occur in a
cancer cell to allow metastasis? (5)
Question 4
Tests reveal a squamous cell
carcinoma of the lung with liver metastases.
Q4.9• Compare the
characteristics of normal and neoplastic cells (4)
Question 4
When you tell him the diagnosis, Mr Jackson becomes
very angry - accusing you of
negligence for not spotting this
earlier.
Q4.10• Aside from anger,
what are the stages of grief in the model proposed by Kubler-Ross (4)
Question 4
You describe to Mr Jackson the
probable prognosis and progression of
the disease.
Q4.11• List one local and two
systemic effects that cancers in general may produce (3)
The Answers
View these on ‘note view’ rather than on full screen – additional
notes are provided for some slides
Haemoptysis? Where’s that wine…
I Infectious / inflammatory Pulmonary tuberculosis
G Genetic / idiopathic
E Endocrine
T Trauma Chest trauma
V Vascular Pulmonary embolism
I Iatrogenic / ingested
N Neoplastic Bronchial carcinoma
O Organs / otherNose: epistaxis; oesophagus: mallory weiss tearLung: bronchiectasis; Heart: mitral stenosis
Two Useful Concepts
Body Mass Index (BMI)
20-25: Ideal
26-30: Overweight
31-35: Obese
Pack Years
> 20 = increased chance complications
PY=Cigs / day
x Yrs20
BMI=Wt (kg)
Ht2 (M)
Carcinogens
Cigarette smoke
Chemicals• PAH• Aromatic amines• Nitrosamines
UV Radiation
Ionising radiation• Radiotherapy• Radon gas (lung)• Industry/military
Carcinogens
Viruses• EBV (Epstein-Barr)• HPV (Papilloma virus)• HBV (Hepatitis B
virus)
Stages in carcinogenesis
• Initiation• Promotion• Progression
Lung cancer
• Male: Female 7:1• Decreasing
• Male peak in 60s• Female peak in 70s• Rare under 25 years
Presenting complaints• 90% symptomatic
– 40% Haemoptysis– 75% Anorexia– 75% Dyspnoea– 75% Cough– 75% Pain
• Remember Weight Loss
• 10% Incidental imaging
Lung Cancer - Diagnosis
• Imaging– Plain film– CT– MRI
• Cytology– Sputum– Bronchoscopic
washings
Biopsy• Peripheral lesions
– Percutaneous biopsy
• Proximal lesions– Bronchoscopic biopsy
• Pleural Effusions– Fine needle aspiration
Lung Cancer
Types
• Small Cell (20-30%)
• Non-small Cell– Large Cell (10-15%)
– Adenocarcinoma (~20%)• Commonest non-smoking
– Squamous cell carcinoma (40-60%)
• Commonest smoking related
Treatment
• Small cell– Early metastasis
– Chemotherapy and radiotherapy first line
• Non-small cell– Surgery first line
• Lobectomy
• Pneumonectomy
– Radio / chemo as req
Invasion and Metastasis
• Invasion is the spread into adjacent tissues – may occur along natural tissue planes such as along nerves
• Metastasis is the spread of cells to distant parts of the body – there are several mechanisms for this
To Metastasise
• Changes occur in only some cells of the tumour
• By random mutation
• Binds to basement membr
• Becomes motile• Becomes able to attach
to extracellular matrix• Becomes able to degrade
extracellular matrix
• Must be able to survive and grow at site of implantation
Growth Characteristics
Benign Malignant
Expands onlyGrows locally
Expands and invades local tissuesMay metastasise
Generally slower Generally faster
Cytoplasmic Characteristics
Benign Malignant
Normal or slight increase in nucleus:cytoplasm ratio
High nucleus:cytoplasm ratio
Resembles cell of origin (well differentiated)
Failure of differentiation
Retains specialisations Loses specialisationsDiploid Range of ploidy
Histological CharacteristicsBenign Malignant
Few Mitoses Many mitoses – some of which are abnormal
Cell uniform throughout tumour
Cells vary in shape and size (cellular pleomorphism) and/orNuclei vary in shape and size (nuclear pleomorphism)
Organised tissue Disorganised tissue
Local and systemic effects
Local• Pressure• Invasion• Ulceration• Obstruction
Systemic• Weight loss
(cachexia)• Loss of appetite
(anorexia)• Fever• Anaemia• General Malaise• Paraneoplastic