Tutorial 3 - Inflammation, cancer & case studies Flashcards
chronic hepatitis leads to? % probabilities?
- fibrotic liver (fibrous scar tissue),
- liver cirrhosis (25% chance), which can then lead to
- liver cancer (3-5%)
state main causes of chronic liver disease?
hepatitis C 26%
alcohol 24%
hepatitis C with alcohol 14%
hepatitis B 11%
t/f: spontaneous regression of HCC is a rare phenomena where it basically just goes away
true
HCC = hepatocellular carcinoma; liver cancer
possible causes spontaenous regression?
- ischaemia
2. immunologic mechanisms
what is Trans-catheter arterial chemoembolization (TACE)?
- restrictive blood supply tumor
- minimally invasive
- chemotherapy + embolization = chemoembolization
how does TACE work?
small embolic particles coated in therapeutic drugs injected selectively through a catheter into an artery which supplies the tumor
these particles block blood supply and induce cytotoxicity
most tumors in liver supplied by which artery?
hepatic proper
by attacking the hepatic proper artery, how does this fight off the tumor (TACE)?
prevents nutrient delivery over time until neovascularisation can take place
what is (typically) the limiting factor for chemotherapy?
systemic exposure
state the 2 mechanisms by which TACE works?
overall effect of this on physiological level?
- block arterial blood supply until neovascularisation
- focused chemotherapy of higher dose. This effect augmented as chemotherapeutic drug not washed out tumor vascular bed by blood flow (as its blocked). This means a higher contact time of tumor and drug
embolization -> ischaemic necrosis -> failure of transmembrane pump, resulting -> greater absoprtion by tumor cells
how was it proven that TACE targets tumor in liver, not liver overall?
tumor 40x more agent then rest of liver. This proven as if inject into hepatic portal vein, only 1/10 of intra-tumoral concentration
so using hepatic artery proper gives 10x higher [drug]
where does ulcerative colitis start?
starts in rectum, may extend for variable distance along colon
define proctisis
anal canal inflamed
how severe can ulcerative colitis (UC) be - how much of colon can be affected?
all of colon and all colonic mucosa can be affected in highly severe cases
symptoms of UC?
diarrhea, blood/ mucus/ pus in faeces
aetiology of UC?
not clear, several hypothesis:
- psychosomatic - stress induced
- infective - enteropathological form e.coli induce
- autoimmune - lymphoid cells cause inflammation
unified explanation: infection triggers inappropriate immune response leading to destruction colonic mucosa
in active UC, the ulcerated areas are _____
hemorrhagic, leading to bloody diarrhoea
explain histology of active UC?
- in-tact mucosa sits above areas of ulceration as islands
- edema
- increased lymphoid cells & plasma cells in lamina propria
- neutrophils in lamina propria and gland epithelium
- neutrophils migrate through walls of glands forming crypt abscesses in gland lumen
- depletion goblet cells
t/f: UC has only local, no systemic effects
false - both
direct local complications of UC?
blood and fluid loss from extensive ulceration
natural history of patients with UC?
10% develop severe disease, need surgery
10% have persistent active disease despite treatment
80% have chronic quiescent colitis with infrequent episodes
In chronic UC, regeneative changes to colonic mucosa leads to?
dysplasia and risk of carcinoma development in colon
There is more risk of dysplasia/ carcinoma development in chronic UC if?
- disease very severe (total colitis)
2. disease duration long (had for 10 years)
In trying to kill cancer, how are most cancer cells killed?
apoptosis is stimulated by drugs given
necrosis means death by?
O2 deprivation