Gastric Neoplasms

1. Gastric Neoplasms
Dr. D.W. Daugherty
Department of Surgery

2. Gastric Adenocarcinoma
Epidemiology
a. Among top 10 causes of cancer related deaths in the
US.
b. Highest incidence in Japan, where it accounts for
approximately 50% of cancer-related deaths among
men and 40% of cancer-related deaths among women.
c. Incidence also high in Chile, Costa Rica, Hungary,
Portugal, Singapore, and Romania.
d. Migration from these areas appears to decrease
incidence.
e. Most strongly related to early infection with H. pylori.
f. No conclusive evidence of correlation with diet.

3. Pre-malignant Lesions
a. Highest risk is associated with polyps.
b. Two main categories of gastric polyps: Hyperplastic
and Adenomatous.
c. Hyperplastic polypsare considered to have NO
neoplastic potential.
d. Adenomatous polyps carry a 10-20% risk for the
development of carcinoma.

4. Hyperplastic polyps
a. Common, occurring in 0.5-1% of general population
and accounting for 70-80% of all gastric polyps.
b. An overgrowth of histologically normal appearing
gastric epthelium.
c. Atypia is rare.
d. Considered to have NO neoplastic potential.
e. Most are asymptomatic.
f. Dyspepsia and vague complaints of epigastric
discomfort are most common.
g. Co-existing gastroduodenal disease is frequently
common.
h. Complications are unsual. GI hemorrhage occurs in less
than 20%.
i. Endoscopic examination with removal is indicated and
sufficient for treatment.

5. Adenomatous polpys
a. Distinct risk for development of malignancy.
b. Atypia is common, and risk for development of
carcinoma is 10-20%. Risk is greatest in polyps over
2cm in diameter and with multiple polyps.
c. Symptoms are similar for those of hyperplastic polyps -
Dyspepsia and vague complaints of epigastric
discomfort are most common.
d. Endoscopic examination with removal for the
pedunculated polyp is indicated and sufficient if
histological exam shows no evidence of cancer.
e. Operative excision is recommended for sessile polyps
larger than 2cm, for polyps with biopsy-proven invasive
carcinoma, and for polyps complicated by pain and/or
bleeding.
f. After removal, routine endoscopic surveillance is
indicated.

6. Gastritis
a. Malignancy appears to be increased in patients with
gastritis associated with pernicious anemia.
b. Characterized by fundic mucosal atrophy, loss of
parietal and chief cells, hypochlorhydria, and
hypergastrinemia. Is present in 3% of people older than
60 years of age.
c. Risk of Gastric CA doubles in patients who have had
pernicious anemia for 5 years or greater.
d. Intestinal metaplasia, presence of intestinal glands in
the gastric mucosa, is also commonly associated with
gastritis and gastric cancer.
e. NO direct evidence has been provided to show the
evolution from metaplasia to dysplasia to carcinoma to
invasive cancer in gastric cancer.

7. Helicobacter Pylori
a. Associated with inflammatory conditions in the
stomach.
b. Seropositivity increases risk for gastric cancer three-
fold.
c. High risk for cancer in the antrum and body; however,
NOT a risk factor for cancers at the esophagastric
junction.
d. Postulated that long term gastric inflammation,
consequent to childhood acquisition of H. pylori, makes
the gastric mucosa more susceptible to environmental
carcinogens.
e. Treated with triple therapy: Proton-pump Inhibitor,
Amoxicillin, and Clarithromycin.

8. Gastric Remnant Cancer
a. Theory that previous gastrectomy increases risk for
subsequent cancer development.
b. Several large, prospective studies show no real
increased risk until after 25 years post-operatively when
the relative risk is increased three-fold.

9. Clinical Features
a. Symptoms not specific.
b. Epigastric pain present in 70%. Pain is often constant,
non-radiating, and unrelieved by food ingestion.
c. Some patients report pain being relieved, at least
temporarily, by antacids or gastric antisecretory drugs.
d. Anorexia, nausea, and weight loss are present in less
than 50% of patients with early gastric CA, but
becomes increasingly common as the disease
progresses.
e. Dysphagia is present in less than 20%. GI hemorrhage
is present in only 5%. Perforation is rare at 1%.
f. Physical examination often unremarkable in early
stages.
g. Stools guiac positive in 33% of patients.
h. Abnormal physical findings indicate late disease:
Cachexia, abdominal mass, hepatomegaly, and
supraclavicular adenopathy usually indicate advanced
metastatic disease.
i. Laboratory tests are un-revealing.

10. Diagnosis and Screening
a. Endoscopy is the most definitive diagnostic method.
b. Biopsy and brushings can be obtained at time of
endoscopy.
c. Use of CT is very limited, with poor accuracy for
diagnosis and staging.
d. Laparoscopy or explorative laparotomy provide only
accurate staging methods.

11. Pathology of Adenocarcinoma: Two distinct histologic sub-types:
Intestinal and Diffuse.
a. Intestinal
1. Malignant cells form glands.
2. Associated with gastric mucosal atrophy, chronic
gastritis, intestinal metaplasia, and dysplasia.
3. Most common in populations at high risk – e.g.
Japan.
4. More common in men and older patients.
5. Bloodbourne metastases.
b. Diffuse
1. No gland formation.
2. Infiltrates as a sheet of loosely adherent cells.
3. Lymphatic invasion.
4. Intraperitoneal metastases common.
5. Occurs in younger patients, women, and in
populations with a lower risk – e.g. United States.
6. Prognosis is less favorable with Diffuse form.

12. Primary Tumor
T1 Confined to mucosa
T2 Involves the mucosa and sub-mucosa,
and extends to but does not penetrate the serosa
T3 Penetrates serosa with or without invasion of adjacent structures
T4 Diffuse involvement on gastric wall without obvious boundries
Regional Lymph Node Involvement
N0 No nodal metastases
N1 Metastases to perigastic lymph nodes in immediate vicinity
N2 Metastases to distant lymph nodes or nodes along both
curvatures of the stomach
Distant Metastases
M0 No distant metastases
M1 Metastases beyond regional nodes
Stage Grouping
Stage I T1, N0, M0
Stage II T2-3, N0, M0
Stage III T1-3, N1-3, M0
Stage IV Unresectable or metastatic

13. 5 year Survival Rates by Stage for Gastric Adenocarcinoma:
a. Stage I: <90%
b. Stage II: 50%
c. Stage III: 15-18%
d. Stage IV: <5%

14. Location
a. Proximal: approximately 45% of tumors, defined as GE
junction, fundus, and body.
b. Distal: approximately 45% of tumors, defined as the
antrum.
c. Diffuse: approximately 10% diffusely involve the
stomach.

15. Treatment
a. Surgical resection is the only hope for cure.
b. Surgical resection goals are two:
1. Maximize chances for cure in pts with local tumor.
2. Provide effective and safe palliation in those with
metastatic disease.
c. Laparoscopy: Diagnostic. Allows visualization of the
liver, omentum, and peritoneal surfaces. Laparoscopy
precludes resection in up to 25% of patients.

16. a. Laparotomy:
1. For early lesions of distal or middle stomach, sub-
total gastrectomy – removing 80% of the stomach
– with gastro-jejunal anastomosis provides
satisfactory 5 year survival.
2. Proximal gastric lesions require total gastrectomy
with esophagojejunostomy OR
esophagogastrectomy with gastroesophageal re-
anastomosis in the cervical or thoracic portion of
the esophagus.
3. Adequate disease free margins must be obtained.
4. The value of extended lymphadectomy in the
treatment of gastric CA is controversial. First large
study in Japan.
a. R1 – Perigastric nodes
b. R2 – Celiac and periduodenal nodes
c. R3 – Celiac, aortic, and esophageal nodes

17. a. Palliative Treatment
1. Does not usually require surgery.
2. Use of endoscopic lasar very successful.
3. Palliative resection has not been shown to increase
survivial.
4. Mean survival is 9 months with or without
palliative treatment.
5. Palliation of symptoms becomes primary role. Can
usually be done non-surgically.
6. For proximal obstructing lesions or those not able
to be treated by lasar endoscopy, a palliative
gastrectomy with Roux-en-Y esophagojejunal
bypass may provide relief.
7. Radiation therapy may play a significant role.
8. Chemotherapy, whether single agent or multi-
modality has proven to be of limited use.

18. Gastric Lymphoma
Clinical Features
a. Stomach is the most common organ involved in extra-
nodal lymphoma.
b. Non-Hodgkin’s lymphoma accounts for 5% of
malignant gastric tumors.
c. Uncommon in children and young adults. Usual
presentation is during the sixth to seventh decades.
d. Symptoms are indistinguishable from gastric
adenocarcinoma: epigastric pain, weight loss, anorexia,
nausea, and vomiting are common.
e. Occult bleeding and anemia are observed in more than
half of patients.

19. Diagnosis
a. Endoscopic examination is the diagnostic method of
choice.
b. Appearance may be ulcerated, polypoid, or infiltrative.
c. Most occur in the middle or distal stomach. Rare in the
proximal stomach.
d. Endoscopic biopsy with cytologic brushings and
ultrasound provides the diagnosis in 90% of cases.
e. Evidence of systemic lymphoma should be sought with
CT of the chest and abdomen to detect
lymphadenopathy, bone marrow biopsy, and biopsy of
enlarged paripheral nodes.
f. Ann Arbor Staging System is Used:

20. Stage I Tumor confined to one lymph node region
Stage IE One extralymphatic organ or site
Stage II Two or more lymph node regions on the same side of the diaphragm
Stage IIE One extralymphatic organ or site and the criteria for stage II
Stage III Lymph node regions on both sides of the diaphragm
Stage IIIE One extralymphatic organ or site and the criteria for stage III
Stage IIIS Splenic involvement and criteria for stage III
Stage IIISE Splenic involvement, one extralymphatic organ or site, and criteria for stage III
Stage IV Diffuse or disseminated disease
Ann Arbor Staging for Gastric Lymphoma

21. Treatment
a. Gastrectomy is the first line treatment:
1. More accurate histologic evaluation is possible
2. The procedure can be curative
3. Eliminates the risk of life-threatening hemorrhage
or perforation. (occurs in 5% of unresected
patients)
b. Role of resection becoming more controversial,
increasing numbers of patients treated with
chemoradiation alone.
c. Extended radical resection not recommended.
Microscopically positive margins do NOT predict local
recurrence in cases when radiation therapy is used post-
op.
d. Survival is closely related to stage. Patients with Stage
II or greater should be considered to have systemic
disease.

22. 5 year Survival Rates by Stage for Gastric Lymphoma:
Stage I: <90%
Stage II: 75%
Stage III: 50%
Stage IV: <10%

23. Gastric Carcinoids
a. Rare, only 0.3% of all gastric tumors, and 3-5% of all
carcinoids.
b. Pernicious anemia increases risk of carcinoid
development, suggested as a result of chronic trophic
stimulation by hypergastrinemia associated with
pernicious anemia.
c. Most commonly in gastric body or fundus.
d. Histologically: Nests of monotonous hyperchromatic
cells. Grossly: reddish-pick to yellow submucosal
nodules in the proximal stomach
e. Invasion is uncommon in lesions less than 2cm
diameter, but increases proportionately to size.
f. Tumors are frequently multiple.
g. Diagnosis is made by endoscopic biopsy.
h. Resection is indicated in almost all cases, and is usually
curative.

24. Gastric Sarcomas
Epidemiology
a. Comprise approximately 3% of gastric malignancies.
b. Leiomyosarcomas are predominant. Angiosarcomas
and fibrosarcomas are rare.
c. Occur in the sixth to seventh decades and equally
among men and women.
d. Frequently grow to a large size.

25. Clinical Features
a. Symptoms identical to those of adenocarcinoma.
Occasionally, with large lesions, an epigastric mass
may be palpated.
b. Symptoms usually related to mass effects with
compression of adjacent structures. GI hemorrhage may
occur secondary to overlying mucosal necrosis.

26. Diagnosis
a. Endoscopic exam and biopsy is the diagnostic method
of choice. But can be negative if the major component
of growth is extraluminal. But, usually the tumors
appear as grey-white masses with a psuedo-capsule
often separating it from surrounding healthy tissue.
b. Graded histologically with the frequency of mitotic
spindles as the prime indicator of tumor aggressiveness.
5-10 mitosis per high power field demonstrate
increased metastasis. In benign disease mitoses are
usually rare or absent.

27. Treatment
a. Intraperitoneal sarcomatosis is frequent as a local
recurrence after resection. Metastasis occurs via
hematogenous spread. Hepatic involvement is common.
b. Do not respond to radiation or chemotherapy.
c. Surgical resection is the treatment of choice. En bloc
resection should be attempted. Lymphadenectomy is
not indicated due to low frequency of lymphatic spread.
Overall survival is approximately 50% at 5 years,

28. Questions ??