GASTRIC CANCER

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					GASTRIC CANCER
 classification
 histopathologic types
 metastasis
 staging
 symptoms of gastric cancer
 diagnosis
 early gastric cancer vs advanced
 treatment
 classification
  histopathologic types
 metastasis
  staging
  symptoms of gastric cancer
  diagnosis
  early gastric cancer vs
  advanced
 treatment
Borrman classification
Broeder'shistologic
gradingsystem
Ming's classification
Lauren classification
                      Lauren classification
Intestinal-type tumors                   Diffuse-type tumors
glandular structure , well               tiny clusters of small cells , malignant
differentiated                           cells are scattered in the CT , poorly
                                         differentiated.
Diffuse inflammatory cell infiltration   widespread through the mucosa, less
and frequent intestinal metaplasia       inflammatory infiltration
Preceded by a pre-cancerous process      More often in women, in younger
and predominate in regions with         patients, and in regions where gastric
incidence of gastric Ca                  cancer is less common ( USA , jordan
                                         )
As regional gastric cancer risk is , it As the incidence of gastric Ca in the
experiences most of the reduction.(in cardia , it is seen with  frequency.
the last 80 years ).
                                         frequent lymphatic invasion,
                                         intraperitoneal metastases.

Good prognosis                           Poor prognosis
 classification
 histopathologic types
 metastasis
 staging
 symptoms of gastric cancer
 diagnosis
 early gastric cancer vs
  advanced
 treatment
 adenocarcinoma 80-
  85%                      adenocarcinoma
 Lymphoma 8-10%           intestinal,diffuse, &
 Squamous cell             mixed
  carcinoma 0.5% , very    Intestinal type(arises
  rare                      from metaplastic
 carcinoids                gastric mucous cells in
 stromal tumors            the setting of chronic
                            gastritis , occurs after
                            the age of 50, 2:1
                            male predominance .
                           Diffuse type : arises de
                            novo from gastric
                            mucous cells,> in
                            young ,female
                            predominance.
Papillary, tubular, or mucinous
adenocarcinoma.
Signet ring cell carcinoma.
Small cell carcinoma.
Undifferentiated carcinoma.

 Grades : G1-G4 for well, moderately,
poorly, and undifferentiated tumors.
 classification
 histopathologic types
 metastasis
  staging
  symptoms of gastric cancer
  diagnosis
  early gastric cancer vs
  advanced
 treatment
Regional lymphatics.                 Onion theory
 Hematogenous (portal and            >> 4 layers of
systemic circulation)first to the         lymphatics around
liver and subsequently                    the stomach
to other organs, including lung and       ,contains 117 l.ns:
bone. They are uncommon in            1.Around the main
                                          vessels.
the absence of nodal disease.
                                      2.Suprapyloric &
                                          infrapyloric l.ns, l.ns
Within the gastric wall (via             on the right & the left
submucosal lymphatics ---> linitis        of the cardia,
plastica)                                 retropancreatic l.ns.
                                      3. l.ns around the hilum
Direct invasion of adjacent              of the liver & spleen ,
organs.                                   paraaortic l.ns.
Peritoneal           seeding(=       4. l.ns around left renal
transcoelomic seeding)when the            vein.
tumor invades the serosa .
>>Rirht   Ovary   (Krukenberg's
tumor)

>>Pelviccul-de-sac(rectovaginal
/rectovesical pouch) (Bloomer's
shelf). Detected as a hard
nodule on DRE.

>>Umbilical adenopathy (Sister
Mary Joseph's node).

>>Leftsupraclavicular
adenopathy (Virchow's node).
 classification
 histopathologic types
 metastasis
   staging
  symptoms of gastric cancer
  diagnosis
  early gastric cancer vs
  advanced
 treatment
Staging (TNM Classification)
Gastric     cancer     is staged
according to the characteristics of
the primary tumor (T), nodal
metastases (N), and presence of
metastatic disease (M).

The most important prognostic
indicators remain the depth of
penetration, local regional lymph
nodes metastasis, and involvement
of adjacent organs.
              Primary Tumor (T)
T1   Tumor limited to mucosa and submucosa regardless
     of its extent or location

T2   Tumor involves the mucosa and submucosa (including
     muscularis propria) and extends to or into the serosa
     but does not penetrate through the serosa
T3   Tumor penetrates through the serosa without
     invading contiguous structures

T4   Tumor penetrates through the serosa and invades the
     contiguous structures
           Nodal Involvement (N)
N0   No metastases to regional lymph nodes
N1   Involvement of perigastric lymph nodes within 3 cm. of
     the primary tumor along the lesser or greater curvature

N2   Involvement of the regional lymph nodes, more than 3
     cm. from the primary tumor, which are removable at
     operation, including those located along the left gastric,
     splenic, celiac, and common hepatic arteries
N3   Involvement of other intra-abdominal lymph nodes
     that are not removable at operation, such as the para-
     aortic, hepatoduodenal, retropancreatic, and mesenteric
     nodes
       Distant Metastasis (M)



M0   No (known) distant metastasis
M1   Distant metastasis present
 classification
 histopathologic types
 metastasis
 staging
 early gastric cancer vs
 advanced
 symptoms of gastric cancer
 diagnosis
 treatment
         Early Gastric Cancer
 this concept comes from japan where
there is a high incidence of gastric ca , &
where 65% of the detected cases of gastric
ca are in early stages ( mainly stage 1),, while
in USA 85-90% of the detected cases are in
the late stages.

Defined as disease involving the mucosa or
submucosa (may be fairly large)± lymph
nodes.  T1 , any N.

5-6% of mucosal and 15 -20% of
submucosal early Ca are accompanied by
positive lymph nodes, so , dont exclude the
possibility of having l.n involvement even in
early stages.
Three types of macroscopic lesions are
describe
(a)Protruded (Type I).elevated 1 mm
(b) Superficial (Type II).
(c) Excavated (Type III).depressed 1 mm

 It represents only 10-15% of diagnosed
  cases in the west.

 Five-year survival after resection
  ranges from 70-95%, depending on
  the presence of nodal involvement.
   Advanced Gastric Cancer


Suggests invasion of the muscularis or
beyond.

Frequently associated with distant or
contiguous spread, have a higher stage.

It represents < 50% of cases in Japan.
> 80% of cases in U S are advanced
gastric Ca at the time of diagnosis.
 classification
 histopathologic types
 metastasis
 staging
 early gastric cancer vs advanced
 symptoms of gastric cancer
 diagnosis
 treatment
Symptoms of early gastric cancer are
vague and unspecific. They may mimic
symptoms of benign gastric ulcer.


Symptoms may not be evident until a
tumor is of sufficient size to interfere with
gastric motor activity, cause obstruction, or
cause bleeding from an ulcerated tumor.
Weight loss (20% - 60%)
Abdominal pain (20% - 95%)
Nausea and anorexia (30%) ,,
vomiting due to pyloric obstruction.
Dysphagia (25%),if the cardia is
involved.
Early satiety and ulcer-type pain
(20%).
Signs or symptoms of
dissemination (10%).like headache ,
back pain , jaundice
 classification
 histopathologic types
 metastasis
 staging
 early gastric cancer vs advanced
 symptoms of gastric cancer
 diagnosis
 treatment
         Routine laboratory tests


 CBC, stool for occult blood , LFT.

In advanced disease, laboratory evidence of
anemia develops.

Liver function tests are usually abnormal with
hepatic metastasis
   Double-contrast barium meal
 Appearance:
(a) Polypoid mass.

(b)Ulcer crater lies in a mass and does not
    extend outside the boundary of the gastric
    wall. Mucosal folds do not radiate toward the
    center of the crater, usually > 1 cm. and are
    surrounded by rigid gastric wall on
    fluoroscopy.

(c)Non-distensible stomach.
Computed tomography scanning
 Gastric wall thickening (0.5-4 cm. and
 correlates with tumor penetration).

 Gastric ulceration (polypoid or sessile
 lesions).

 Invasion of the gastrohepatic ligament,
 spleen, or diaphragm.

 Distal metastases.
 ** peritoneal seeding wont be seen by CT , it needs lap.
 Staging.
Flexible endoscopy and biopsy

   it’s the gold standard for diagnosing
  gastric ca.

   we can take :
  -4 quadrant Bx for tissue study or
  - brush cytology .
 Endoscopic ultrasonography

 Other Diagnostic Modalities:
Gastric acid analysis can diagnose
patients with hypo- and achlorhydria,
which are associated with  risk for
gastric Ca (should be screened).

Molecular biologic techniques, (e.g.
cytologic evaluation for p53 or p21
protein).
 classification
 histopathologic types
 metastasis
 staging
 early gastric cancer vs advanced
 symptoms of gastric cancer
 diagnosis
 treatment
 patients    with advanced stage ( 3,4)
palliative treatment.
Patients with profound weight loss and
metabolic complications of their cancer
should be treated.
 Patients without obstruction or bleeding but
who have distal metastases should not be
explored.
Patients with obstruction or bleeding should
still be considered for exploration, as palliative
resection is better than palliative bypass).
In patients with metastatic obstructing
proximal       gastric    tumors,      prosthetic
endoesophageal tubes or endoscopic laser
therapy can be used.
 patients   with   early   stages   (1,2)   curative
treatment.

Surgical resection is the only potentially curative
therapy.

The extent of gastric resection should be tailored
to the proximal extent of the primary lesion and
geared toward obtaining negative proximal and
distal margins.

Different resections for distal, middle, and
proximal lesions. In diffuse tumors, total
gastrectomy may be the only option available to
achieve adequate margins.
Surgical            resection      and
lymphadenectomy can be described as
follows:
    D0 resection = incomplete removal of
    perigastric LN.
    D1 resection = complete removal of
    perigastric nodes.
    D2 resection = D1 +LN along the
    named arteries of the stomach.
    D3 resection = D2 + removal of the
    nodes of the celiac axis.
    D4 resection = D3 + para-aortic
    nodes.
Early Gastric Cancer
D1 resection is usually       curative
(survival rates of 95%).

Endoscopic        treatment       using
cauterization, local injection of drugs,
and laser therapy.
Advanced Gastric Cancer
Gastric resection includes:
   (a)Subtotal gastrectomy for antral         or
pyloric lesions.
   (b)Subtotal or total gastrectomy for
middle-third lesions).
   (c)Total gastrectomy with
esophagojejunostomy for proximal-
      third, GEJ, or extensive middle-third
lesions.

In addition, the perigastric lymph nodes
along the lesser and greater curvatures and
the lymph nodes along the left gastric artery
are typically removed. The lesser and greater
omenta are resected.
   Adjuvant Therapy
    Chemotherapy

Overall results are mixed but
generally disappointing. Only 2 of
16 randomized trials showed a
survival benefit for the treatment
group.

Three Japanese trials have
confirmed a survival benefit for
mitomycin C alone or futrafur and
mitomycin C.
Adjuvant Therapy
Chemoradiotherapy


  Results are mixed
          Adjuvant Therapy
        Chemoimmunotherapy
The immune depression encourages the
growth of tumor cells in certain patients.

Numerous immunomodulators have been
found to enhance T-cell function and stimulate
natural killer cells.

Immunotherapy alone has rarely been shown
to be effective against residual tumors.

The advantages are greatest in patients with
Stage III and IV disease or patients who
underwent D0 resection.
Postoperative complications of gastrectomy
  -Leakage of the oesophagojejunostomy
   should be uncommon in experienced
  hands. When it does occur it can often be managed
  conservatively
  as the Roux-en-Y reconstruction means that it is
  mainly saliva and ingested food that leaks.

  - Some patients may establish
  a fistula from the wound or drain site .

  - leakage from the duodenal stump
  usually due to a degree of distal obstruction and
  care must be taken when performing the Roux-en-Y
  anastomosis that there is no kinking.
- Paraduodenal collections can be drained
radiologically, which will often convert the collection into an
external fistula.

- Biliary peritonitis requires a laparotomy and peritoneal
toilet, and in this circumstance it is best to leave a Foley
catheter in the duodenum to establish a controlled duodenal
fistula. If it is established that there is no distal obstruction, or if
any such obstruction is managed, then with time the fistula will
close.

-The presence of septic collections along with a very radical
vascular dissection may lead to catastrophic secondary
haemorrhage from the exposed or divided blood vessels.
This situation may be very difficult to manage, whether or not
reoperation or interventional radiology is employed.
Long-term complications of surgery
Considering the radical nature of the total gastrectomy it
is surprising that many patients, particularly younger ones,
have good functional results.

- However, most patients will have a reduced
capacity, particularly in the short term.so They need to be
given detailed nutritional advice, the substance of which
is to eat small meals often while the jejunum or small
gastric remnant adapts.

- In fact, there is very little functional difference between
patients who have a total gastrectomy and those who
have a subtotal gastrectomy.
-They infrequently suffer from the
complications of gastric surgery, such as
dumping and diarrhoea.

- Nutritional deficiencies
may occur and the patient should be
monitored with this in mind.
The loss of the parietal mass leads to
vitamin B12 deficiency and
replacement should be given routinely.
Pattern of relapse following surgical treatment

- the most common site of relapse following
radical gastrectomy is the gastric bed, representing
inadequate extirpation of the primary tumour.

- Widespread nodal intraperitoneal
metastases, distant nodal metastases and liver
metastases are all common.

- Dissemination to the lung and bones usually only
occurs after liver metastases are already established
References :
-Bailey & love’s short practice of surgery , 25th edition.
- schwartz principle of surgery , 9th edition.
- Robbins basic pathology , 8th edition

				
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posted:12/20/2011
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