Pathophysiology of Gastric Cancer

PATHOPHYSIOLOGY OF GASTRIC CANCER  Etiolog: +nknown

Precipitating Factors: - Diet/Nutrition: high fat, low fiber, undercooked/ charred foods - Stress - Bowel Habits - Lifest Lifestyle yle:: smok smoking ing,, alcoho alcoholis lism m

Predisposing Factors: - ge: ge: !" y/o abo#e bo#e - Heredity - $n#i $n#iro ronm nmen ent: t: e%& e%&os osur uree to carcinogens - 'ender   - (re#i (re#iou ouss 'ast 'astri ric/ c/ )ol )olon on// *ectal )a

ffects normal cells

 &roctooncogenesis

utation in the DN mismatch re&air genes

cti#ation of oncogenes

 Negati#e effect on DN re&air 

umor su&&ressors deacti#ates

utated cell multi&lies

+ncontrolled &roliferation )ells grow and di#ide .uickly

(oly&osis collagen inacti#ates

DN re&air genes inacti#ates

(ermits unchecked cellular re&lication

)ancer cells di#ide and &roliferate

ncreased cell di#ision

A

!

C

A

!

)ancer cells undergo further mutation

cti#ation of oncogenes (re#ents &o&tosis

ncreased lifes&an of  affected cells

*e&licates 0ust like normal cells ncreased number of  malignant cells

C

n#ades e&ithelia of '

lters genetic make u& of e&ithelium

Stem cell transformation

Lateral and downward s&read of abnormal cells

ltered stem cell re&licates

*e&laces normal cells

denoma

" "

"

$%tends to ad0acent cells

denocarcinoma

$%tends downwards

1bstructs &assageways

$%tends to small intestines

ass/ umor 

$%tends to anus

$%tends to rectum

umor bleeds norectal ass

ffects ad0acent structures

Hematoche2ia/ hemo&tisis/ hematemesis Blood loss

Lym&hatic s&read anemia $%tends to #aginal wall

n#ades/ com&resses ner#es Back/ &el#ic  &ain

Bowel obstruction

bdominal  &ain

)hange in bowel habbits Loss/ decreased  bowel mo#ements *etention of  fecal matter 

 &allor  se&sis  bleeding

3oul smelling discharge