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Ca stomach |
Ca stomach
Etio
1) Environmntl & dietary factrs
-incidnc incresd in persons who consum red meat, cabbage, spices, spirits, saltfish etc
-smoked salmon fish ws rsponsbl for incresd incidnc, probably relatd 2 releas of polycyclic hydrocarbons & aromatic amino acids
-smoking, spicy food & alcohol takn ovr a period of many yrs produc chronic gastritis whch may change in2 Ca stomch
2) Precancerous conditions
i)Atrophic gastritis
due 2 smoking, continuos ingestion of drugs, reflux of bile in2 stomach etc
ii)Pernicious anaemia
incresd risk 4to6 tims more
it caures atrophic gastritis & precipitats Ca stomach fundus
iii)pts wid hypogamaglobulinemia 50fold r @ risk
iv) H. pylori infn results in atrophic gastritis, folowd by intestinal typ of gastric mucosa, den metaplasia, den dysplasia. Eventuly leads 2 intestinl typ of gastric cancer
v)TypeA gastritis predispos 2 proximl Ca stomach
TypeB gastritis predispos 2 distl Ca stomach
vi)Adenomatous polyps whch ocur in antrum hav highest risk of malignant transformation
vii)Menetrier's diseas is protein losing enteropathy, along wid giant hypertrophy of gastric mucosal folds. It is a precancerous condition
viii)Gastric ulcer benign
ix)Previous GJ / gastric resection predisposes aftr a period of 15-20yrs
3)Genetic & familial factors
-can run in families, hwevr only 10% of pts giv family H/O Ca stomach
-Ca stomch more comon in bld grup A pts
PATHOLOGY & PATHO TYPE
A) Gross types
i. Cauliflowr like growth wid friable tisue
ii. Infiltrativ lesion wid dense submucosal fibrosis whch convert stomach in2 a small, contracted, functionless stomch i.e Linitis Plastica / Leather Bottle Stomach
iii. Ulcerativ wid clasicl evrted edges wid central slough
iv. Ulcer cancer refers 2 carcinoma arising in a pre-existing gastric ulcer
v. Colloid carcinoma- malignant cels sepratd by colloid material
B) Depending on depth of invasion
1)Early Gastric Cancer- Cancer limitd 2 mucosa & submucosa wid/widout lymph node invo(T1 & N) represented as Japanese Clasificn
Type I protruding
Type IIa elevated superficial
Type IIb flat superfial
Type IIc depressd superficial
Type III & IIc excavated
Criticism for early gastric cancer- node negativ early gastic cancer is more dan 95%
2)Advancd gastric cancer
refers 2 involv of muscularis mucosa &/or serosa wid/widout invo of lymph nodes
Borrmann's classn
Type I single polypoidal Ca
Type II uleroproliferativ
Type III ulcerativ
Type IV difuse Ca
C/F
very often pts wud hav vague symptoms- early satiety, flaulence, discomfort, pain upper abdo
1)Silent growth but manifests as secondaries in liver, ascites, Virchow's node etc
2)Obstructn @ pyloric antrum wid featurs of vomiting wid/widout bld
3)Lump in abdo whch is hard & iregular
4)Insidious in onset- anaemia, anorexia, asthenia of short duration
5)Dyspepsia in man ovr age of 40
Featurs of stomch mass
i)stomch moves wid respi
ii)upper border of stomach mass cn b mad out
iii)anatomicl location of mass- rt hypochondrium in a pyloric mass, epigastrium & lt hypochondrium in a mass arising 4m body of stomch
iv)knee elbow position- mass does fall forwards unles fixd
v)mass may hav intrinsic mobility
SPREAD
1)Penetration of gastric serosa- dis is d most imp prognostic indicator. Wen serosa is not penetrated 50% surviv for 5yr aftr resectn
2)Lymphatic spread
lymph nod invo is a poor progno indicator
invo of 4/more nodes is less favourabl
**Lymphatic Zones
lymphatic drainag 4m stomch clasified in2 4 zones
Zone1- in gastrocolic omentum along rt gastroepiploic vessels, dis drains pyloric antrum & lowr half of greater curvature
Zone2- lies in gastroepiploic omentum & gastrosplenic ligament along lt gastroepiploic vessels. Dis drains uper half of greater curvature
Zone3- lies in lesser omentum draining proximl 2/3rd of stomch. 4m here lymph drains in2 perioesophageal LN
Zone4- 4m distal portion of lesser curve & pylorus along hepatic artery & rt gastric artery in2 para aortic nodes
3)Bld spread
most comon sites r liver & lungs, produces extensiv secondaries. Dey r signs of inoperability
4)Transcoelomic spread
results in ascites, Krukenberg Tumor-bilat bulky ovarian deposits & rectovesicl deposits
INVEST
1)complete bld pictur
20% pts of early gastric Ca hav anaemia, iron defi- microcytic
2)routine examn, fasting & postprandial sugars, ECG, renal function for fitness b4 surgry
3)Videoendoscopy
to knw extent of lesion
to confirm diagno
to take 6 quadrant biopsy
4)Ultrasound, CT, MRI
to rule out secรถndaries in liver
to look for enlargd coeliac nodes
ascites can b demonstrtd
to detect Krukenberg tumor
useful to detect metastasis
5)Endoscopic USG
differentiat early gastric Ca 4m advncd tumors in 80% of pts
6)Barium meal may show intrinsic, persistent, iregulr, filling defect. Useful in Linitis Plastica study
TNM STAGING
T : Primary tumor
T0 : no evidence of prim tumor
Tis : Ca in situ
T1 : invasion of lamina propria / submucosa
T2 : invasion of muscularis propria / subserosa
T3 : penetration of serosa
T4 : invasion of adjacent structurs
N : Lymph nodes
N0 : no regionl LN
N1 : 1-6 LN positiv for maligncy
N2 : 7-15 LN positiv
N3 : more dan 15 LN
M : Metastasis
M0 : no distant metastasis
M1 : distant metastasis presnt
HISTOPATH
it is an adenoCa of stomch. Basicly 2 typs of gastric Ca as per Lauren's classn, also calld D.I.O. classn
D- Difuse more comon in young, females, & poor prognosis
I- Intestinl more comon in eldrly males, shows areas of intestinl metaplasia, better prognosis
O- Others mixd lesions leather bottle stomch or linitis plastica is poorly diffrentiatd wid anaplastic cels
Rx
Surgery is main modality of Rx
1)Curative resections
i)Ca of pyloric antrum & body of stomch
radical subtotal gastrectomy whch includs removl of 60-70% of stomch wid greater omentum along wid enlargd LN folowd by GJ anastomo
ii)Ca of fundus
oesophago-gastrectomy, in whch removl of uper part of stomch, lowr end of osophagus, wid regionl LN, spleen, folowd by oesophagogastric anasto or oesophagojejunl anasto
iii)difuse grwth(linitis plastica)
radicl total gastrectomy folowd by oesophagojejunostomy
2)Palliativ surgery
i)Ca pyloric antrum inoperable- palliativ ant GJ is done 2 relieve vomiting, by anastomosing a jejunal loop 2 stomch in prepyloric region
ii)Palliativ gastrectomy to get rid of ulceratd, necrotic / bleeding lesion
3)Chemotherapy
partialy responds
in abt 30% cases givn @ advncd stage
Inj. 5-FU(Flurouracil) 500mg IV daily for 5 days evry 28 days
*Mech of action- it is an antimetabolite & acts by interfering wid DNA synthesis
-Combn of 5FU wid adriamycin, mitomycin, cisplastin tried but more toxic
FAM & ECF r popular drugs
-Intraperitรถneal mitomycin & mitomycin C-impregnated charcol also usd