Transcript Types of Gastric cancer

GASTRIC TUMOURS
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Anatomy of the stomach
Aetiology of Gastric cancer
Types of Gastric cancer
Pathology of Gastric Cancer
Evaluation of Gastric Cancer
Treatment of Gastric Cancer
ANATOMY:
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The stomach J-shaped. The stomach
has two surfaces (the anterior &
posterior), two curvatures (the greater &
lesser), two orifices (the cardia &
pylorus). It has fundus, body and pyloric
antrum.
BLOOD SUPPLY:
a.
b.
c.
d.
e.
The left gastric artery
Right gastric artery
Right gastro-epiploic artery
Left gastro-epiploic artery
Short gastric arteries
The corresponding veins drain into
portal system. The lymphatic drainage
of the stomach corresponding its blood
supply.
Anatomy
• Stomach has five layers:
– Mucosa
• Epithelium, lamina propria, and muscularis
mucosae*
–
–
–
–
Submucosa
Smooth muscle layer
Subserosa
Serosa
AETIOLOGY:
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Gastric cancer is the second most
common fatal cancer in the world with
high frequency in Japan.
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The disease presents most commonly in
the 5th and 6th decades of life and affect
males twice as often as females.
Contn…
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The cause of the disease multistep process
but several predisposing factors attributed
to cause the disease :
a.
b.
c.
d.
Environment
Diet
Heredity
Achlorhydria
e. Atrophic gastritis
f. Chronic gastric ulcer
g. Adenomatous polyps
h. Blood group A
i. H. Pyloric colonisation
TYPES OF GASTRIC CANCER:
A. Benign Tumours
B. Malignant Tumours
TYPES OF GASTRIC CANCER:
A. Benign Tumours
B. Malignant Tumours
THE BENIGN TUMORS:
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Although benign tumors can
occur in the stomach most
gastric tumours are malignant.
 The benign groups includes:-
1. Non-neoplastic gastric polyps
2. Adenomas
3. Neoplastic gastric polyps
4. Smooth muscles tumours benign
(Leiomyomas)
5. Polyposis Syndrome (eg:- Polyposis coli,
Juvenile polyps and P.J. Syndrome)
6. Other benign tumours are fibromas,
pancreas and
angiomas.
neurofibromas, aberrat
PATHOLOGY OF GASTRIC (MALIGNANT)
TUMOURS:

The gastric cancer may arise in
the antrum (50%), the gastric
body (30%), the fundus or
oesophago-gastric juntion (20%).
 Types of Malignant Tumours:
a. Adenocarcinoma
b. Leiomyosarcoma
c. Lymphomas
d. Carcinoid Tumours
 The macroscopic forms of gastric cancers are
classified by (Bormann classification) into:-
1. Polypoid or Proliferative
2. Ulcerating
3. Ulcerating/Infiltrating
4. Diffuse Infiltrating (LinnitusPlastica)
Microscopically the tumours commonly
adenocarcinoma
with
range
of
differentiation.
The most useful to
clinician and epidemiologist is Lauren
Histological Classification:
a. Intestinal gastric cancer
b. Diffuse gastric cancer
Gastric Carcinoma
• Diffuse
• Intestinal
•
•
•
•
•
•
•
•
M:F 1:1
Onset Middle Age
5 yr surv overall <10%
Aetiology
– Diet
– H. pylori
M:F 2:1
Onset Middle Age
5 yr surv overall 20%
Aetiology
– Unknown
– Blood group A association
– H. pylori
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Early Gastric Cancer: Defined as
cancer which is confined to the
mucosa and submucosa regardless of lymph nodes status.
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Advanced
Gastric
Cancer:
Defined as tumor that has involved
the muscularis propria of the
stomach wall.
Gastric Neoplasm:
Pathology:
Gastric dysplasia --->
precursor of gastric CA
Early gastric cancer:
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–
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Limited to the mucosa and
submucosa, regardless of
LN status
70% are well differentiated
Cure rate is 90%
STAGING OF GASTRIC CANCER:
a. TNM System
b. CT Staging
c. PHNS Staging System (Japanese)
 P-factor (Peritoneal dissemination)
 H-factor (The presence of hepatic metastases)
 N-factor (Lymphnodes involvement)
 S-factor (Serosal invasion)
TNM Classification System
• Distant metastasis (M)
MX Presence of distant metastasis cannot be
assessed
M0 No distant metastasis
M1 Distant metastasis (may be further specified
according to size of occurrence)
SPREAD OF GASTRIC CANCER:
The diffuse type spreads rapidly
through the submucosal and serosal
lymphatic and penetrates the gastric
wall at early stage, the intestinal variety
remains localized for a while and has less
tendency to disseminate.
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The spread by:
1.
2.
3.
4.
Direct (loco regional)
Lymphatic
Blood (Haematogenous)
Transcoelomic
Clinical Manifestation:
1. Weight loss due to anorexia and early satiety is
the most common symptoms
2. Abdominal pain (not severe) common
3. Nausea / vomiting
4. Chronic occult blood loss is common;
GIT bleeding (5%)
5. Dysphagia (cardia involvement)
Clinical Manifestation:
6. Paraneoplastic syndromes ( Trousseau’s
syndrome – thrombophlebitis; acanthosis
nigricans – hyperpigmentation of axilla and
groin; peripheral neuropathy)
7. Signs of distant metastasis:
a.
b.
c.
d.
e.
Hepatomegally / ascites
Krukenbergs tumor
Blummers shelf (drop metastasis)
Virchow’s node
Sister Joseph node (pathognomonic of advances
dse)
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SUMMARY:
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Often asymptomatic until late stage.
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Marked weight loss
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Anorexia
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Feeling of abdominal fullness or discomfort
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Epigastric mass
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Iron Deficiency Anaemia
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Left supraclavicular mass (Troisier’s Sign)

Obstructive Jaundice (Secondary in porta
hepatitis)
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Pelvic mass (Krukenberg)
EVALUATION OF GASTRIC CANCER:
 History
 Clinical Examination
 Investigations
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The clinical features of gastric cancer
may arise from local disease, its
complications or its metastases.
INVESTIGATIONS:
A. Upper gastero intestinal endoscopy
with multiple biopsy and brush
cytology
B. Radiology:
 CT Scan of the chest and abdomen
 USS upper abdomen
 Barium meal
C. Diagnostic laparoscopy
Diagnosis:
1. UGIS (double contrast)
2. Endoscopy (Biopsy / Ultrasound)
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•
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GOLD STANDARD
Best pre-operative staging
Needle aspiration of LN w/ ultrasound guidance
Can even give preop neoadjuvant tx
3. CT scan (intravenous and oral contrast):
•
For pre-operative staging
4. Whole body Positron Emission Tomography
scanning (PET):
•
Tumor cell preferentially accumulate positronemitting 18F fluorodeoxyglucose.
Laboratory
• Assists in determining optimal therapy.
• CBC identifies anemia, with may be caused
by bleeding, liver dysfunction, or poor
nutrition.
• 30% have anemia.
• Electrolyte panels and LFTs are also
essential to better characterize patients
clinical state.
Investigations for patients with
gastric cancer
• Endoscopy & biopsy
• Performance status
• Physiological assessment
– Cardio-pulmonary function
• CT chest & abdomen
• EUS (endoscopic ultrasound)
• Laparoscopy
CT scanning
• Technique
– Spiral CT of chest and
abdomen
Laparoscopy
• Inspect peritoneal surfaces, liver surface.
• Identification of advanced disease avoids
non-therapeutic laparotomy in 25%.
• Patients with small volume metastases in
peritoneum or liver have a life expectancy
of 3-9 months, thus rarely benefit from
palliative resection.
Screening of Gastric Cancer
•
Patients at risk for gastric CA should
undergo yearly endoscopy and biopsy:
1.
2.
3.
4.
5.
6.
Familial adenomatous polyposis
Hereditary nonpolyposis colorectal cancer
Gastric adenomas
Menetrier’s disease
Intestinal metaplasia or dysplasia
Remote gastrectomy or gastrojejunostomy
TREATMENTS OF GASTRIC CANCER:
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Surgery (Early or Advanced Cancer)
Distal tumours which involve the lower ½ (sub-total or
partial gasterectomy).
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Proximal tumours which involve the
body (total
gasterectomy).

fundus, cardia or
Surgical Treatment
TREATMENT:
SURGERY:
– The only curative tx for gastric cancer
– Except:
1. Can’t tolerate abdominal surgery
2. Overwhelming metastasis
–
–
–
Palliation is poor w/ non-resective operations
GOAL: resect all tumors, w/ negative margins
(5cm) and adequate lymphadenectomy (need
for RFS)
Enbloc resection of adjacent organ is done if
needed.
TREATMENT:
SURGERY:
Radical subtotal gastrectomy
•
Standard operation for gastric
cancer
Organs resected:
1. Distal 75% of stomach
2. 2 cm of duodenum
3. Greater & lesser omentum
4. Ligation of R & L gastric
artery and gastroepiploic
vesels
5. Billroth II gastojejunostomy
TREATMENT:
SURGERY:
Radical subtotal gastrectomy
•
Standard operation for gastric
cancer
If gastric remnant left is small
(<20%) do Roux-en-Y
reconstruction
Endoscopic Resection of Gastric
Carcinoma
Criteria:
1. Tumor < 2cm in size
2. Node negative
3. Tumor confined on the mucosa
Nodes metastasis is < 1%:
1. No mucosal ulceration
2. No lymphatic invasions
3. <3cm tumor
Treatment of gastric cancer
• Endoscopic treatment
– EMR (endoscopic mucosal resection)
– ablation
• Surgery
• Multimodal treatment
– Neo-adjuvant
– Adjuvant
• Palliative treatment
Endsocopic mucosal resection
• T1 mucosal disease
– Minimal risk of LN
metastases
• Various techniques
• Specimen obtained
Distal Pancreatectomy
• Associated with marked increase in
morbidity & mortality with or without
splenectomy
• Indications for pancreatectomy:
– Direct invasion of the tail of the pancreas
– Likelihood of splenic artery nodal involvement
Surgical Treatment
Inoperable tumours: Whenever possible it is
advisable to do even a limited gastric resection. If
resection is impossible an anterior
gastrojejunostomy.
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Indications for Splenectomy
• If macroscopic disease can be resected &
the operation is potentially curative then en
bloc splenectomy or
pancreaticosplenectomy is worthwhile.
• If it is more palliative then this benefit must
be weighed against the potential
complications of splenectomy and more
extensive operation
Chemotherapy for gastric cancer
(Pre-operatve & post-operative)
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Radiotherapy
(Pre-intra & post-operatively)
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Adjuvant Therapy
• Rationale is to provide additional locoregional control.
• Radiotherapy- studies show improved
survival, lower rates of local recurrence
when compared to surgery alone.
• In unresectable patients, higher 4 year
survival with mutimodal tx, in comparison
to chemo alone.
Chemotherapy
• Numerous randomized clinical trials
comparing combination chemotherapy in
the adjuvant setting to surgery alone did not
demonstrate a consistent survival benefit.
• The most widely used regimen is 5-FU,
doxorubicin, and mitomycin-c. The addition
of leukovorin did not increase response
rates.
Advanced Unresectable Disease
• Surgery is for palliation, pain, allowing oral
intake
• Radiation provides relief from bleeding,
obstruction and pain in 50-75%. Median
duration of palliation is 4-18 months
Outcome
• 5-year survival for a curative resection is
30-50% for stage II disease, 10-25% for
stage III disease.
• Adjuvant therapy because of high incidence
of local and systemic failure.
• A recent Intergroup 0116 randomized study
offers evidence of a survival benefit
associated with postoperative
chemoradiotherapy
Complications
• Mortality 1-2%
• Anastamotic leak, bleeding, ileus, transit
failure, cholecystitis, pancreatitis,
pulmonary infections, and
thromboembolism.
• Late complications include dumping
syndrome, vitamin B-12 deficiency, reflux
esophagitis, osteoporosis.
OTHER GASTRIC TUMOURS:
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Gastric Lymphomas:
Primary lymphomas of the stomach of the
(NHL).
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The symptoms are similar to those of
gastric cancer (adenocarcinoma).
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The diagnosis is made principally from
endoscopic examination with biopsy and
cytology.
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CT Scanning is important in staging the
disease.
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non Hodgkin’s type
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Treatment:
- Well-localized disease should be treated
with resection (surgery) followed by
radiotherapy or chemotherapy.
- Extensive disease by adjuvant chemotherapy & radiotherapy than surgery.
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Leiomyosarcoma:
Arise in the stomach representing 1% of
gastric tumors.
They may be sessile or pedanculated projecting into the gastric
lumen or extragastrical or both (dumb-bell
tumour).
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Presentation due to blood loss anaemia
or vague dyspepsia.
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or epigastric mass
Malignancy is suggested by the size more than 5 cm and
confirmed by
noting increased mitosis on histology.
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Stromal tumours
• GIST (Gastro-Intestinal Stromal Tumour)
– Presentation
• Incidental
• Bleeding
– Pathology
•
•
•
•
•
Blend sheets of spindle cells
Previously mistaken for leiomyomata
Origin cell – interstitial cell of Cahal
C-kit +ve
Actin -ve
Stromal tumours
• Prognostic factors
– Size (>4cm)
– Resection margins
– Mitoses
– Vacuoles on EUS
Stromal tumours
• Surgical Treatment
– Excision with clear margins
– No lymphadenectomy required
• Non –surgical treatment
– Glivec (imatinib)
– Recurrence / inoperable
– ? Neoadjuvant / adjuvant
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Gastric Carcinoid Tumour:
Are very rare. There is established association
between
atrophic gastritis & carcinoid & pernicious anemia.

Gastric carcinoids are best treated by
very small by
endoscopic resection.

local resection. If
Gastric Carcinoid Tumours
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•
•
•
<1% of gastric tumours
4-41% of GIT carcinoid tumours
Most ECL/argyrophil cell origin (80%)
3 clinico-pathological subtypes:
– Type 1, 2 & 3
Gastric Carcinoid Tumours
• Type 1 : Hypergastrinaemia with
Autoimmune chronic atrophic gastritis
(Type A)
– Pernicious anaemia
• Type 2 : Hypergastrinaemia with
hypertrophic gastropathy
– Zollinger-Ellison syndrome
• Type 3 : Sporadic, no relation to
hypergastrinaemia
Gastric Carcinoid Tumours : Rindi
et al
n = 45
Type 1
Type 2
Type 3
Mc+/-SMc
26 (92%)
6 (86%)
3 (30%)
Musc Prop
1 (4%)
1 (14%)
3 (30%)
Serosa
1 (4%)
0
4 (40%)
Multiple
18 (64%)
6 (86%)
0
Solitary
10 (36%)
1 (14%)
10 (100%)
Metastases
0
2 (29%)
6 (60%)
Type 1 Gastric Carcinoid
• Type 1 Gastric carcinoid tumours :
associated with Type A Autoimmune
Chronic Active Gastritis
• Autoimmune process leads to destruction
and gradual atrophy of chief and parietal
cells of body/fundus - sparing of
body/fundic neuroendocrine cells
• Hypochlorhydria or achlorhydria
Gastric Carcinoid Tumours
• Hyperplastic precursor sequence
• Hypergastrinaemia -- Neuroendocrine
hyperplasia -- Dysplasia -- Neoplasia
• Pernicious anaemia only present in 20-46%
of patients (latent effect)
• Natural history : most probably remain
stationary; some regress and some
metastasize
Results of therapy – stomach cancer
• Surgery with curative intent
– 42% of patients
• 5 year survival – 60%
– Node positive - 35%
– Node negative - 88%
Sue Ling et al (1993) BMJ
Multimodal therapy
• Adjuvant chemotherapy
–
–
–
–
Possible small advantage
OR 0.84 (0.74 – 0.96)
Western 0.96
Asian 0.58
• Janunger 2001
• Neo-adjuvant
chemotherapy (ECF)
– MAGIC trial
• Surgery +/- chemo
– 503 patients
– Higher curative resection
rate
• 79% vs 69%
– Better survival at 2 years
• 48% vs 40%
Palliative chemotherapy
• Median survival benefit 3 – 6 months
• Combination therapy superior
• 50% gain improvement in QOL