2. Gastric carcinoma is the 4th most common cancer and second leading cause
of cancer death.
Can occur at any age. But peak incidence is 50-70 years.
It is more aggressive in younger age groups and is more common in males.
It is especially prevalent in East Asia and South America and has been
increasing in developing countries, which now have almost two thirds of all
distal gastric cancer cases. In contrast, rates have been decreasing in the
United States.
Japan has the highest rate of gastric cancer. Although there has been an
increase in proximal tumors in Japan,most of cases are distal gastric cancers.
3. Risk Factors:
Nutritional
Salted meat or fish
High nitrate consumption
High complex carbohydrate
consumption
Environmental
Poor food preparation (smoked, salted)
Lack of refrigeration
Poor drinking water (e.g., contaminated
well water)
Smoking
Social
Low social class
Medical
Previous gastrectomy
H. pylori infection
Gastric atrophy and gastritis
Adenomatous polyps
Pernicious anemia
Other
Male
4. Hereditary risk factors
• E-cadherin gene mutation-----80% lifetime incidence of developing
Hereditary diffuse form of gastric cancer.
• Familial adenomatous polyposis---85% of patients have fundic gland
polyps, more than 50% containing a somatic adenomatous polyposis coli
mutation, which places these patients at risk of developing gastric cancer.
• Li-Fraumeni syndrome (p53 mutation)---These patients are at risk for
numerous malignancies, including gastric cancer.
• Hereditary nonpolyposis colorectal cancer, or Lynch syndrome, which
accounts for 2% to 3% of all colon and rectal cancers and is associated with
microsatellite instability, is also associated with an increased risk of gastric
and ovarian cancers.
7. Gastric cancer can be divided into two types:
1. Early gastric cancer
2. Advanced gastric cancer.
8. Early gastric cancer
Early gastric cancer is defined as cancer limited to the mucosa and
submucosa with or without lymph node involvement.
Approximately 10% of patients with early gastric cancer will have
lymph node metastases
This type of cancer is eminently curable, and even early gastric
cancers associated with lymph node involvement have 5-year survival
rates in the region of 90%
9. Type I
(protruding)
Polypoid tumors (> 3mm elevation)
Type IIa Slightly elevated tumors. (superficial
elevated)( < 3mm elevation)
Type IIb Tumors without elevation or depression.
(superficial flat)
Type IIc Slightly depressed tumors. (superficial
depressed)
Type III
(excavated)
Tumors with deep depression
Japanese classification of Early gastric cancer
11. Lauren Classification System
INTESTINAL DIFFUSE
Environmental Familial
Gastric atrophy, intestinal metaplasia Blood type A
Men > women Women > men
Increasing incidence with age Younger age group
Gland formation Poorly differentiated, signet ring cells
Haematogenous spread Transmural, lymphatic spread
Microsatellite instability Decreased E-cadherin
APC gene mutations p53, p16 inactivation
p53, p16 inactivation
14. CLINICAL PRESENTATION
• Unfortunately 80% of the patients are asymptomatic. The symptoms are often vague at
first and resemble other gastric ailments such as ulcer disease.
• Indigestion/ heart burn.
• Bloating / fullness after meals.
• Loss of appetite
• Nausea
• Abdominal discomfort especially after meals.
• Pain in the upper back or chest.
• Hematemesis and malena.
• Difficulty in swallowing
• Change of bowel habits
• In advanced stages: Anemia ,weight loss
15. SIGNS OF METASTATIC DISEASE
• VIRCHOWS NODE
• SISTER MARY JOSEPH NODULE
• HEPATOMEGALY
• JAUNDICE
• ASCITES
• KRUKENBERG TUMOUR-----Drop metastases to ovaries
• BLUMERS SHELF----------Peritoneal metastasis
• IRISH NODE-------Enlarged axillary lymph node
17. N: Regional lymph nodes
N0 No regional lymph-node metastasis
N1 Metastasis in 1 to 2 regional lymph nodes
N2 Metastasis in 3 to 6 regional lymph nodes
N3 Metastasis in 7 or more regional lymph nodes
N3a Metastasis in 7 to 15 regional lymph nodes
N3b Metastasis in 16 or more regional lymph nodes
T: Primary tumor
T0 No evidence of primary tumor
Tis Carcinoma in situ; intraepithelial tumor without
invasion of the lamina propria, high-grade
dysplasia
T1 Tumor invades lamina propria, muscularis
mucosae, or submucosa
T1a Tumor invades lamina propria or muscularis
mucosae
T1b Tumor invades submucosa
T2 Tumor invades muscularispropria
T3 Tumor invades subserosa
T4 Tumor perforates serosa or invades adjacent
structures
T4a Tumor perforates serosa
T4b Tumor invades adjacent structures
M: Distant metastasis
M0 No distant metastasis
M1 Distant metastasis
18. Diagnostic and Staging Work up
• The main modalities for staging gastric adenocarcinoma and guiding
therapy are:
1. Endoscopy
2.EUS( Endo ultrasound)
3. Cross-sectional imaging such as CT, MRI, or positron
emission tomography (PET).
4.Diagnostic laparoscopy.
19. Endoscopy
• Flexible endoscopy is the essential tool for the diagnosis of gastric cancer. It allows
visualization of the tumor, provides tissue for pathologic diagnosis, and can serve as a
treatment for patients with obstruction or bleeding .
• On initial diagnostic endoscopy, if a suspicious mass or ulcer is encountered in the stomach, it
is essential to obtain adequate tissue to confirm the correct diagnosis histologically.
• Multiple biopsy specimens (six to eight) should be taken of different areas of the lesion using endoscopic
biopsy forceps. A single biopsy specimen results in a diagnostic sensitivity of 70%, whereas
seven biopsy specimens increases this yield to 98%.
• Small lesions (<2 cm in diameter) can be resected at the time of initial diagnostic endoscopy
using endoscopic mucosal resection
20. Endoscopic ultrasound.
• Flexible upper endoscopy combined with ultrasound is now part of the standard workup for staging
and risk-stratifying patients with gastric cancer .
• EUS provides the most accurate evaluation of the depth of tumor invasion (T category of TNM staging
system) and possible nodal involvement (N
• EUS is performed using a flexible endoscope with a 7.5-MHz to 12-MHz ultrasound transducer.
• The stomach is filled with water to distend it and provide an acoustic window, and the stomach wall
is visualized as five alternating hypoechoic and hyperechoic layers.
• The mucosa and submucosa represent the first three layers (T1).
• The fourth layer is the muscularis propria, invasion of which is a T2 tumor.
• Expansion of the tumor beyond the muscularis propria causing an irregular border correlates with
expansion into the subserosa, or a T3 tumor. The serosa is the fifth layer, and loss of this bright line
correlates with penetration through it, indicating a T4a tumor. Direct invasion of surrounding
structures, including named vessels, indicates a T4b tumor
21.
22.
23. COMPUTED TOMOGRAPHY(CT)
• CT with oral or intravenous contrast is the primary method for detection of intra-
abdominal metastatic disease, with an overall detection rate of approximately
85%.
• The sensitivity of CT for imaging peritoneal metastases is only 51%, with a high
specificity of 96% if the study is positive.
• CT has also been used in locoregional staging.
• The accuracy of T and N stages as determined by CT is less accurate than EUS.
24.
25. Positron emission tomography(PET)
• The use of PET for initial staging is limited because only 50% of gastric
cancers are PET avid.
• However, in patients with positive PET scans presumed to have advanced
disease and patients considered for neoadjuvant therapy, there may be a
role for PET.
• PET may be an effective modality for monitoring response to these
therapies, sparing unresponsive patients to further toxic treatment.
• Additionally, in a study of patients with locally advanced tumors (T3/4) or
N-positive on EUS, PET was able to detect occult metastases that were
missed on regular CT in 10% of patients
26. Diagnostic Laparoscopy.
• Staging laparoscopy is an integral part of the standard workup for gastric cancer.
• The high rate of occult metastatic disease makes laparoscopy an attractive staging
modality.
• The overall sensitivity of laparoscopy for detecting metastatic disease was greater
than 95%.
• Staging laparoscopy has been advocated as part of the workup for gastric cancer
to avoid unnecessary laparotomy in patients.
27. ADENOCARCINOMA
CT, Endoscopy With EUS
Metastatic disease
Symptomatic
(Bleeding, obstruction)
Consider Palliative
Resection
Asymptomatic
Refer to medical
oncology
No metastatic disease
Laproscopy
No metastatic disease
Resection with nodal harvest
29. Endoscopic mucosal Resection(EMR)
1. Tumor limited to the mucosa.
2. No lymphovascular invasion
3. Tumor smaller than 2 cm,
4. No ulceration, and
5. Well or moderately well differentiated histopathology.
• Endoscopic resection can be performed using one of two techniques:EMR or ESD.
• The basic principle for EMR involves elevating the tumor using a saline injection and then
encircling the affected mucosa using a snare device to excise it with electrocautery.
• Perforation rates are low, and bleeding rates are approximately 15%
30.
31. Endoscopic submucosal dissection(ESD):
• Submucosal invasion less than 500 μm
• All intramucosal tumors without ulceration
• Differentiated mucosal tumors smaller than 3 cm regardless of ulceration
status
• Tumors with limited (SM1) submucosal invasion that were smaller than 3 cm
and without ulceration
This technique involves marking the borders of the lesion using electrocautery.
A submucosal injection of epinephrine with indigo carmine hydrodissects the
lesion, and an insulation-tipped knife is used to remove the lesion by dissecting
a submucosal plane deep to the tumor and removing it en bloc.
32.
33. Surgical Treatment
• Complete resection of a gastric tumor with a wide margin of normal stomach
remains the standard of care for resection.
• All patients without metastatic disease are candidates for curative resection.
• The extent of resection depends on the location of the tumor in the stomach
and size of the tumor.
• The standard technique is via a laparotomy; however, minimally invasive
techniques, including laparoscopy and completely endoscopic resection for
very early tumors,
34. Surgical procedures
Distal Gastrectomy----For tumours of the distal stomach, including the body and antrum,
• The principles of surgical resection are to obtain resection margins that are grossly at least 5
cm from the visible or palpable mass.
• The specimen should be sent for frozen-section pathological analysis to access margin status.
• Ideally, margins should be microscopically free from cancer, often referred to as an R0
resection.
• Total gastrectomy----For proximal lesions of the fundus or cardia,
35. • R status, first described by Hermanek in 1994, is used to describe tumor
status after resection and is important for determining the adequacy of
surgery
• R 0----microscopically margin negative resection, in which no gross or
microscopic tumor remains in the tumour bed.
• R 1----removal of all macroscopic disease, but microscopic margins are
positive for tumor.
• R 2----indicates gross residual disease.
• Long-term survival can be expected only after an R0 resection.
36. Lymph node
station no
description
1 Right paracardial
2 Left paracardial
3 Lesser curvature
4sa Short gastric
4sb Left gastroepiploic
4d Right gastroepiploic
5 Suprapyloric
6 infrapyloric
7 Left gastric artery
8a Anterior common hepatic
8p Posterior common hepatic
9 Celiac artery
Lymph node
station no
Description
10 Splenic hilum
11p Proximal spleen
11d Distal Splenic
12 a Left Hepatoduodenal
12b p Posterior Hepatoduodenal
13 Retropancreatic
14 v Superior mesenteric vein
14 a Superior mesenteric artery
15 Mid colic
16 al Aortic Hiatus
16a2 b1 Para aortic, middle
16 b2 Para aortic caudal
37.
38. Lymph node dissection:
• D1 lymphadenectomy :Dissection involving only perigastric nodes.
• D2 dissection: Clearance of the celiac axis, with or without splenectomy,
• D3 lymphadenectomy:Complete clearance of the celiac axis and periaortic
nodes.
• At least 15 lymph nodes be removed for adequate staging purposes
• Only the number of nodes, not the location, was a significant predictor of
mortality
• When the number of nodes was used for staging, there was more consistency in
survival rates, providing higher quality prognostic information for patients within
a given stage
39. D1 vs D2 Lymphadenectomy
• MRC and Dutch D1D2 trials: D2 lymphadenectomy resulted in higher rates of perioperative morbidity and
increased mortality.
• MRC trial showed no difference in recurrence-free or overall survival outcomes at greater than 5-year
follow-up.
• Dutch D1D2 trial showed lower recurrence rates and disease-free survival at 15-year follow-up in the D2
group. However no difference in overall survival (possibly because of the increase in perioperative
mortality for D2 patients).
• A meta-analysis of 12 randomized trials comparing lymph node dissections found that when the spleen
was preserved, a D2 dissection resulted in superior recurrence-free survival, with a trend toward increased
overall survival.
• In the absence of tumor invasion, the spleen should be spared during gastrectomy for gastric cancer
• D2 lymph node dissection is likely oncologically superior but must be performed in a safe manner without
added perioperative mortality to be of long-term benefit to the patient.
40. Gastric reconstructive techniques
• Billroth I---- Gastroduodenostomy
• Billroth II----Gastrojejunostomy or oesophagojejunostomy with roux-
en- y reconstruction
42. Detachment of the greater omentum from the colon
through the avascular plane
The anterior mesocolon is separated from the
underlying vessels and posterior layer
43. $
%
A. and B. The duodenal staple/suture line is invaginated with
interrupted Lembert sutures
The duodenum is divided 1–2 cm distal to the pylorus.
44. 0 With the proximal resection line delineated, the stomach is transected either between clamps or with a surgical stapler.
45. For a Billroth II anastomosis, a gastrojejunal anastomosis is
performed with a running absorbable monofilament sutures.
For Roux-en-Y reconstruction, the jejunum is divided 10–15
cm distal to the ligament of Treitz.
46. The distal segment of the transected jejunum is brought to lie along the posterior-inferior aspect of the gastric margin, and a
posterior row of Lembert type sutures is place to attach the jejunum to the gastric wall. B. Two 3-0 PDS sutures are placed
immediately next to each other and run in opposite directions until they meet in the anterior aspect of the anastomosis. C. An
anterior row of interrupted reinforcing Lembert suture is placed to complete the superior anastomosis.
$ & %
47. The two segments of jejunum to be anastomosed are aligned parallel to each other, and a 5-cm antimesenteric anastomosis
is created.
50. $ %
Completed Roux-en-Y reconstruction after total
gastrectomy.
. Creation of a jejunal S pouch. B. Creation of a jejunal J pouch.
51. Adjuvant and Neoadjuvant Therapy
Gastric cancer remains a biologically aggressive cancer, with high
recurrence and mortality rates.
R0 resection demonstrated recurrence rates of almost 30%, with most
patients experiencing recurrence within the first 2 years.
Underlying these poor outcomes ,the initial chemotherapy regimens for
gastric cancer provide little benefit.
Numerous primary studies and meta-analyses have shown inconclusive
results.
52. Adjuvant and Neoadjuvant Therapy
The Southwest Oncology Group (9008/INT-0116) reported a randomized controlled trial of 556
patients who had undergone curative gastrectomy alone or gastrectomy combined
with adjuvant 5-fluorouracil and radiotherapy.
This study demonstrated a significant benefit for adjuvant therapy for overall survival
(41% versus 50%) and recurrence-free survival (41% versus 64%).
As a result, adjuvant chemoradiation has become the standard of care for patients
undergoing curative gastrectomy in the United States
In the CLASSIC trial, which randomly assigned 1035 patients undergoing gastrectomy with D2 lymph node dissection
to either surgery alone or surgery followed by eight 3-week cycles of capecitabine plus oxaliplatin.
The trial was stopped early after patients in the adjuvant therapy group were found to have significantly higher
rates of disease-free survival (74% versus 59%, P < .0001) and overall survival (83% versus 78%, P < .05) at median
3-year follow-up.
In the chemotherapy group, 67% of patients received all eight cycles as planned per protocol.
53. Adjuvant and Neoadjuvant Therapy
The ARTIST trial evaluated whether the addition of adjuvant radiotherapy would be beneficial to patients
undergoing gastrectomy with D2 dissection and subsequent adjuvant chemotherapy with capecitabine and
cisplatin.
There was no difference in outcomes found between the adjuvant chemotherapy and adjuvant chemotherapy
plus radiotherapy groups, but radiotherapy improved disease-free survival in patients who had lymph node
metastases on resection.
The most significant results are those of the MAGIC trial, a randomized controlled study of 503 patients with stage
stage II or higher gastric cancer that compared perioperative chemotherapy with surgery alone.
The treatment group received three 3-week cycles of epirubicin, cisplatin, and continuous infusion of 5-
fluorouracil preoperatively and three additional cycles postoperatively.
More than 90% of patients who started the preoperative chemotherapy were able to complete it; however, only
65% of these patients went on to receive postoperative chemotherapy, and only 50% successfully completed
both.
The treatment group had significantly better pathologic results and long-term outcomes. The chemotherapy
group had a higher percentage of T1 and T2 tumors in the final specimens, along with a higher proportion of
limited (N0 and N1) nodal disease compared with the surgery arm alone.
54. Summary:
Gastric cancer is one of the most common causes of cancer death in the world
The outlook is generally poor, owing to the advanced stage of the tumour at presentation
The aetiology of gastric cancer is multifactorial, but H. pylori is an important factor for
distal but not proximal gastric cancer
Early gastric cancer is associated with very high cure rates
In western resource-rich countries, proximal gastric cancer is now more common than
distal cancer and is usually of the diffuse type
The treatment of curable cases is by radical surgery and removal of the second tier of
nodes (around the principal arterial trunks) may be advantageous
Gastric cancer is chemosensitive and chemotherapy improves survival in patients having
surgery for the condition and in advanced disease.
