This document discusses gastric cancer, including its epidemiology, risk factors, diagnosis, treatment, and outcomes. Some key points: - Gastric cancer is the 4th most common cancer worldwide and the 15th most common in the US. Incidence has declined significantly over the last century. - Risk factors include H. pylori infection, smoking, diet high in salted/smoked foods, and adenomatous polyps. - Diagnosis is typically made via endoscopy with biopsy. Staging may involve endoscopic ultrasound, CT scan, or laparoscopy. - Treatment is usually surgical resection with D1 or D2 lymph node dissection and chemotherapy/radiation. Total or

1. Topic: Gastric Cancer
Presented by:
M. Awais
Mehran ahmad khan
Abrar khan
Sayyed M. Omar
Kazim ahmad
Presented to:
Dr. Asghar shabir

2. Epidemiology
• Gastric cancer was the fourth most common cancer in the world in
2004, and is expected to remain fourth in 2005.
• Worldwide there are 930,000 new cases and 700,000 deaths per
year. Sixty percent of new cases occur in developing countries.
• There is tremendous geographic variation, with the highest death
rates in Chile, the former Soviet Union, China, and Japan.

3. Epidemiology
• In the United States gastric cancer is the 15th most common cancer,
with 21,860 new cases expected this year, and 11,550 deaths.
• The incidence of gastric cancer has declined significantly worldwide
in the last century, with a marked decline in the US since the 1930s.

4. Epidemiology
• In New York State there were an average of 1955 cases annually
between 1998-2002, with 1070 deaths.
• Male to female ratio of 2:1 in the US; 3:2 in New York.
• Median age at diagnosis is 65 years (40-70). Incidence increases with
age, peaking in the 7th decade.

5. Risk Factors
• Low fat or protein consumption
• Salted meat or fish
• High nitrate consumption
• High complex carbohydrate consumption

6. Risk Factors
• Environment
• Poor food preparation (smoked/salted)
• Lack of refridgeration
• Poor drinking water (well water)
• Smoking

7. Risk Factors
• Social
• Low social class (except in Japan)
• Medical
• Prior gastric surgery
• H. pylori infection
• Gastric atrophy and gastritis
• Adenomatous polyps
• Male gender

8. Risk Factors
• Helicobacter pylori
• Presence of IgG to H. pylori in a given population correlates with local
incidence and mortality from gastric cancer.
• Different strains elicit different antibody responses. The cagA strain causes
more mucosal inflammation and thus a higher risk of gastric cancer than
cagA-negative strains.

9. Risk Factors
• Adenomatous polyps
• 10-20% risk of developing cancer, especially in lesions greater than 2 cm.
• Multiple lesions increase the risk of developing cancer.
• Presence of polyps increase the chance of developing cancer in the
remainder of mucosa.
• Endoscopic surveillance is required after removal of polyps.

10. Anatomy
• Most of the blood supply to the stomach is from the celiac artery.
• Four main arteries:
• Left and right gastric along the lesser curvature
• Left and right gastroepiploic along the greater curvature.
• Blood supply to the proximal stomach also comes from the inferior
phrenic and short gastric arteries

11. Anatomy
• Occasionally (15-20%) an aberrant left hepatic artery arises from the
left gastric – a concern if the left gastric needs to be divided.
• The extensive anastomotic connections between these arteries allow,
in most cases, three of the four vessels to be ligated as long as the
arcades between the curvatures are not disturbed.

13. Anatomy
• Venous drainage parallels the arterial supply
• Left and right gastric veins drain into the portal vein
• Right gastroepiploic drains into the SMV
• Left gastroepiploic drains into the splenic vein

14. Anatomy
• Lymphatic drainage is into four zones:
• Superior gastric
• Suprapyloric
• Pancreaticolienal
• Inferior gastric/subpyloric
• All four drain into the celiac group of nodes and into the thoracic
duct.
• Gastric cancers drain into any of these groups regardless of location
of the tumor.

15. Anatomy
• Innervation:
• Parasympathetic via the vagus.
• Left anterior and right posterior.
• Sympathetic via the celiac plexus.

16. Clinical Presentation
• Symptoms are often absent in early stages, and when present are
often ignored, missed, or mistaken for another disease process.
• Vague discomfort and/or indigestion
• Epigastric pain that is constant, non-radiating, and unrelieved by food
ingestion.
• Proximal tumors may present with dysphagia.
• Antral tumors may present with outlet obstruction.

17. Clinical Presentation
• Diffuse mural disease may present with early satiety due to
decreased distensibility.
• Up to 15% of patients develop hematemesis and 40% are anemic at
presentation.

18. Clinical Presentation
• Unfortunately most patients present in later stages of disease, with
evidence of metastatic or locally advanced tumor.
• Palpable abdominal mass, ovarian mass, supraclavicular or periumbilical
lymph nodes.
• Obstruction from tumor invasion into transverse colon.
• Hepatomegaly, jaundice, ascites, and cachexia.

19. Diagnosis
• Endoscopy is the diagnostic method of choice.
• With multiple biopsies (seven or more) the diagnostic accuracy approaches
98%.
• Cytologic brushings can also be obtained.
• Size, morphology, and location of tumor can be documented, as well as any
other mucosal abnormalities.

20. Endoscopy

21. Endoscopy

22. Diagnosis
•Double contrast barium
swallow has 90%
accuracy and is cost
effective.
• No ability to distinguish
between malignant and
benign ulcers.

23. Diagnosis
• Endoscopic Ultrasound (EUS) is a newer modality that is being used
in some center to help stage the tumor.
• Extent of wall invasion and lymph node involvement can be assessed.
• Overall accuracy is 75%.
• Poor for T2 tumors (38%)
• Better for T1 (80%) and T3 (90%)
• Remains operator dependent.

24. Preoperative Workup
• Once diagnosis of gastric cancer has been made, CT scan is useful for
evaluation of any distant disease.
• Limited in detecting early primary and small (<5mm) metastatic tumors.
• Accuracy of lymph node staging ranges from 25 to 86%.
• If CT scan is negative, then laparoscopy is recommended as the next
step in evaluation.

25. Preoperative Workup
• Laparoscopy detected metastatic disease in 23 to 37% of patients
deemed eligible for curative resection by CT scan.
• Laparoscopy improves palliation in these patients by avoiding
unnecessary laparotomy in about one fourth of patients presumed to
have local disease on CT scan.

27. Treatment
Surgical resection remains the mainstay of
treatment and is the only curative option.
More recently pre- and post-chemoradiation
therapy has been scrutinized to see if there is any
benefit to survival.
The issue of extent of resection appears to have
been settled. As long as adequate tumor margins
are achieved, subtotal gastrectomy has the same
survival as total, with decreased morbidity.

28. Surgical Treatment
Aggressive resection of gastric cancer is justified in
the absence of distant metastatic spread.
The surgery is tailored mainly to the location of the
tumor and known pattern of spread.
R0 resection should be achieved, with a minimum
of 6cm margins from gross tumor.
R0 – tumor free margins
R1 – microscopic disease
R2 – gross tumor at margins
Minimum of 15 nodes should be removed.

29. Surgical Treatment
• Tumors in the cardia and proximal stomach account for 35-50% of
gastric adenocarcinomas. For these tumors a total gastrectomy
should be performed, as opposed to proximal gastric resection which
is associated with higher morbidity and mortality rates.
• Distal tumors may be removed by distal gastrectomy as long as
adequate margins are achieved.

30. Surgical Treatment
The extent of lymphadenectomy remains
controversial.
The JGCA classifies the lymph node basins into 16
basins, and are grouped according to the location of
the primary tumor as either D1, D2, or D3 nodes. In
general:
D1 – removal of group 1 nodes along the lesser and
greater curvature.
D2 – D1 plus group 2 nodes along the left gastric,
common hepatic, celiac, and splenic arteries.
D3 – D2 plus para-aortic and distal lymph nodes

31. Surgical Treatment
A 1993 survey by the ACS showed a 77.1%
resection rate in 18,365 patients, with a
postoperative mortality rate of 7.2% and 5-year
survival rate of 19%. Of these only 4.7% were D2
dissections.
In comparison, the Japanese routinely perform D2
dissections, with 5-year survival rates above 50%.
Although earlier detection accounts for much of the
survival benefit, when comparing cancers in the
same stage, the Japanese continue to have
improved survival.

32. Survival Outcomes
0
20
40
60
80
100
120
Stage I Stage II Stage III Stage IV
US
Japan

33. Surgical Treatment
• Based on this and other retrospective data, four randomized studies
comparing D1 to D2 dissections have been conducted.
• All four trials, including two large ones from the Netherlands and
Britain all show the same data; that D2 dissection significantly
increases morbidity and mortality without any significant increase in
survival.

34. Surgical Treatment
• Splenectomy and pancreatectomy were found to be important risk
factors for morbidity and mortality after D2 dissection.
• In the DGCT trial a subgroup analysis of patients who underwent D2
without splenectomy and/or pancreatectomy had a significantly
improved survival benefit.
• A randomized British trial also supported these findings in stage II
and III disease.

35. Surgical Treatment
• Based on these findings, many groups are recommending “over-D1”
lymphadenectomy for gastric cancers in Western society.
• The large difference between the Japanese results and Western
results remains largely an enigma.

36. Surgical Treatment
• Choice of reanastamosis depends on extent of resection.
• Very distal gastrectomies may be reanastamosed via a Billroth I, II, or
Roux-en-Y.
• Subtotal gastrectomies will require a Billroth II or Roux-en-Y.
• Total gastrectomies are best served with a Roux-en-Y anastamosis.

37. Outcomes
• What can you expect?
• Patients who have undergone a potentially curative resection have an
average 5-year survival of 24 to 57%.
• More useful survival rates are stratified by stage of disease.

39. Outcomes
• Recurrence rates remain high, from 40 to 80% depending on the
series being quoted.
• Locoregional failure rate 38 to 45%, with most recurrence in the
gastric remnant at the anastamosis, gastric bed, and lymph nodes.
• Surveillance is important. Patients should be followed every 4
months for the first year, then 6 months for 2 more years. Yearly
endoscopy should be performed for subtotal gastrectomies.

40. Choice of Operation
• Open gastrectomy with lymph node dissection – at least D1 – is the
current operative standard.
• Laparoscopic gastrectomy has been shown to be safe with similar
survival for patients with distal cancer.
• Learning curve needs to be overcome, which may be difficult with
the decreasing number of gastric cancer cases in the U.S.

41. Thank you.