Week 3 - Lecture 3a - Clinical Models Pt.1 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Lung cancer pathophysiology

A

leading cause of cancer deaths world wide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

lung cancer patho # 2

A

tumour growth is initiated by mutations that can

  • activate oncogenes
  • subdue tumour suppressor genes
  • cause deletion in chromosome 3

lung cancer is the end stage of multiple mutations and cellular transformation

  1. tumour enlarges
  2. penetrates epithelial layer
  3. moves into lung tissue, pleural cavity, chest wall (Seeding)
  4. metastatic spread : lymph channels, blood vessels

lung cancer metastases are tropic to bone, liver, brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

lung cancer patho #3

A
tumours originate most frequently in the epithelial lining of the 
- bronchi
-bronchioles 
-alveoli 
four subtypes 
1. adenocarcinoma (35%) - C
2. squamous cell carcinoma (30%) - A
3. small cell carcinoma (20%) - B
4. Large cell carcinoma (15%) - D
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

adenocarcinoma (lung cancer)

A

develop in peripheral bronchiolar and alveolar lung tissue
leads to pleural fibrosis and adhesions
further subdivisions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

squamous cell carcinoma (lung cancer patho)

A

cell injury of bronchiolar columnar epithelium (smoking) triggers metaplasia – dysplasia – carcinoma in situ – invasive carcinoma

tumour cells can be detected in sputum (coughed up from respiratory tract)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

small cell carcinoma

A

highly malignant
grows and develops metastases rapidly
tumour cells cause hemorhharge and necrosis
strongly linked to smoking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

large cell carcinoma

A

tumour cells are large
high levels of anaplasia
metastasise readily
diagnosis is based on exclusion of others

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

subtypes prevalence vary by gender

A

adenocarcinoma : most common in women and non smokers
small cell carcinoma : higher rate in males
squamous cell carcinoma : higher rate in males, linked to smoking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

clinical manifestations of lung cancer

A
common clinical manifestations relates to location 
- persistent cough 
-hemoptysis 
-chest pain
-shortness of breath 
often ignored as 'smoker's cough' 

common general manifestations are present
paraneoplastic manifestations are present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Lung cancer diagnostic criteria

A

history taking, physical examination, imaging

  • bronchoscopy
  • chest x ray
  • MRI/CT/ultrasound
  • carcinoembryonic antigen (CEA) may be present
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

prognosis for lung cancer is dependant on

A

CEA level
ability to surgically remove the tumour
lymph node involvement
presence of metastasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Lung cancer treatment

A

based on tumour type

  1. small cell carcinoma
    - chemotherapy
    - - more likely to respond
    - - more likely to be widely disseminated at diagnosis
      • patients develop distant metastases
      • surgical resection and radiation : limited contribution to long term survival

non small cell carcinoma : treatment depends on the ability to resect (surgery) (adenocarcinoma, squamous cell carcinoma, and large cell)
-resectable : may be cured by surgery alone or with chemotherapy combination.

  • non resectable : local control of tumour growth with radiation, cure is unlikely
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

lung cancer treatment part 2

A

least favourable prognosis

  • small cell carcinoma
  • large cell carcinoma
many lung carcinoma are not detected until tumour is well advanced 
early symptoms (chronic cough ) often ignored

overall 5 year survival rate 15%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

colorectal cancer patho

A
exact cause is often not clear 
primary risk factor : age
90% of cases in adults diagnosed over >50 
multiple lifestyle risk factors 
protection 
- selenium, ACE vitamins, veggies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

colorectal cancer

A

tumours are most often of epithelial origin

  • adenoma (benign)
  • adenocarcinoma (malignant)

three groups of colorectal cancer

  1. non - neoplastic polyps (not generally considered a cancer precursor)
  2. neoplastic polyps (adenomatous polyps, adenomas, increased carcinoma development, considered a cancer precursor)
  3. cancers (most often adenocarcinoma)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

colorectal cancer patho cont’ 3

A

number of major deleterious mutations required to promote tumour development : average 5-7
number of major deleterious mutations in cancerous tumours of the colon/rectum : average 9

two pathways identified to lead to carcinoma development

  • series of events triggering chromosomal instability (85%)
  • loss of tumour suppressor ability
  • -imparied DNA repair
  • mutations in the APC tumour suppressor gene (adenomatous polyposis coli) lead adenomatous polyp (precursor to malignant tumour)
replication errors (15%) 
-  chromosomes remain intact, defects in DNA repair
17
Q

colorectal patho pt 4

A

in both mutations (chromosomal instability and replication errors)

  • cellular transformation in mucosal epithelium begins at the base of the crypts
  • cells move to the surface, die and slough off
  • with APC (adenomatous polyposis coli) mutation, tumour cells resist apoptosis and accumulate on the bowel surface
  • continue to proliferate to form benign adenomatous polyps (precursor)
  • mutation of DCC (deleted in colon cancer) and P53 tumour suppressor gene leads to further transformation and malignant tumour
18
Q

colorectal cancer : clinical manifestations

A

manifestations depend on location and characteristics pf the tumour

early stages : asymptomatic
enlargement of tumour : ulceration and haemorrhage
- tumour is along ascending colon : occult blood in stool
-tumour is along descending colon or rectum : frank blood in stool
- abdominal pain
- bowel obstruction
-anaemia : the result of blood loss in the stool
- change in bowel habits

common general manifestations are present
paraneoplastic manifestations are present

19
Q

diagnostic criteria : colorectal cancer

A

history taking, P/E
rectal cancer : Digital examination

colon cancers : colonoscopy (direct visualisation )
recommended >50 yrs

20
Q

treatment of colorectal cancer

A

when localised in bowel : highly treatable and often curable

  • localised tumour : surgery- results in cure in 50% of patients

locally advanced or metastatic disease : combination drug chemotherapy and radiation

prognosis depends on

  • location of the tumour
  • degree of penetration
  • bowel obstruction or perforation
  • lymph node involvement
  • presence of distant metastasis (usually liver)

resectable (surgically cut) hepatic metastasis at diagnosis (50% of patient) 5 year survival rate of 25-40%

21
Q

Brain cancer patho

A

brain cancer affect men more frequently than women
caucasians are affected more than other races
cause is unknown
- exposure to ionising radiation during treatment increase risk

metastasis of other cancer types to the brain is much more common than primary brain tumours (10:1 ratio)

metastasis originates most commonly : lung, breast, skin, colon

tropic tumours

  • preference for cerebral hemispheres (80%)
  • cerebellum (15%)
  • Brainstem(5%)
22
Q

pt 2 Patho brain cancer

A

primary tumour originate from

  • glial cells : non-neurone in the CNS and PNS
    • astrocytes, oliodendrocytes, microglia

Meninges : membranous covering of the brain

schwann cells : produce myelin and collagen

  • schwannoma : within the brain, spinal nerve, peripheral nerves
  • rarely malignant

ectopic tissues : embryonic cells migrated to brain and spinal cord

  • lipoma (embryonic adipose tissue)
  • slow growth - undetected for lifetime
23
Q

Brain cancer patho : primary tumour

A
glial cell origin: glioma
specific astrocyte origin : astrocytoma 
- most common tumour originating in brain 
-differentiation level varies at diagnosis 
-20% well differentiated 
-40% highly undifferentiated 
(rest in between) 
Benign or malignant 
-as glioma enlarge 
-- impinge on vital brain structures 
--become fatal 
--metastases development is rare
24
Q

Brain cancer patho

A

meninges meningioma
-emerge middle/late adulthood
slow growing
erode the cranium

25
Q

brain cancer clinical manifestation

A

depend on size and location of tumour
- neurologic deficit appear as the tumour erodes functional neurons
- sensory and motor loss
– visual changes, numbness, weakness paralysis
-cognitive and personality changes
pressure increase in cranium : growing tumour/inflammation /fluid accumulation
- headache
-vomiting

cell irritation
- seizures

tumour compression of respiratory and cardiac centre : death

26
Q

brain cancer diagnostic criteria

A

history P/E

neurological examination

  • testing cranial nerve
  • reflexes
  • sensory
  • motor
direct visualisation 
Brain scan 
CT/MRI
-X-ray
-Cerebral angiography
PET scan
27
Q

Brain cancer diagnostic criteria classification

A

TNM classification is not used for brain tumours

  • tumour size is less relevant than the location and histology
  • the brain and spinal cord have no lymphatics
  • metastatic disease spread is rare
28
Q

brain cancer treatment

A

treatment depends on
location
extent
nature of neoplasm

primary tumours : surgical resection

  • goal to remove it completely
  • preserve neuro function

radiation
chemo
- spinal canal
-directly in brain during surgery

widespread tumours : whole brain radiation
palliative care for seizures