Early Gastric Carcinoama: Definition, Etiology, risk factors, Pathogenesis, Japanese endoscopic classification, Endoscopic diagnosis, Management- EMR, ESD Recent advances and future prospects

1. Early Gastric Cancer
(EGC)
Dr. Devajyoti Guin
Postgraduate, General Surgery
St. John’s Medical College Hospital
Bangalore, India.

2. EGC
• Risk factors and pathogenesis
• Clinical features
• Definition of EGC
• Classifications
• Endoscopic diagnosis
• Endoscopic surgery
• Follow up
• Future prospects

3. Introduction
• Ca Stomach- 2nd most common cause of
death
• Males (2:1)
• Blacks
• Older age (>7th decade)
• Shift of site- distal to proximal (cardia) 
smoking, alcohol abuse.

4. Risk Factors
Acquired factors
• Nutritional
High salt consumption
High nitrate consumption
Low dietary vitamin A and C
Poor food preparation (smoked, salt cured)
Lack of refrigeration
Poor drinking water (well water)
• Occupational
Rubber workers
Coal workers
• Cigarette smoking

5. Risk Factors
• Helicobacter pylori, Epstein-Barr virus
• Radiation exposure
• Prior gastric surgery- benign gastric ulcer disease (2-6%)
Genetic factors (1-3%)
• Type A blood
• Pernicious anemia
• Family history
• Hereditary nonpolyposis colon cancer
• Li-Fraumeni syndrome

6. Pathogenesis
• Correa Model:
• H.pylori- CagA strain
–Mucosal inflammation
– IgG antibodies
–Host response- IL-1

7. Precursor lesions
• Adenomatous gastric polyps
• Chronic atrophic gastritis
• Dysplasia
• Intestinal metaplasia
• Menetrier's disease (hypoproteinemic
hypertrophic gastropathy)

8. Definition- EGC
• EGC is a cancer in which tumor invasion is
confined to the mucosa or submucosa
(T1) regardless of the presence of lymph
node metastasis.
Japanese Gastric Cancer
Association, “Japanese
classification of gastric
carcinoma—2nd English
edition,” Gastric Cancer, vol.
1, no. 1, pp. 10–24, 1998.

9. EGC
• Good prognosis
• Can be cured by minimally invasive
approaches.
• 5-year survival rates of EGC:
–99% when limited to the mucosa
–96% when the submucosa is invaded

10. EGC
• Detection of EGC- increasing recently- Korea
and Japan  d/t screening by gastrofiberscopy
or upper G.I. series.
• Japan ~50% tumors are diagnosed early.
• Only 5%-10% in the United States.

11. Classifications
• 1926-
• 1942- Border’s classification- degree of
cellular differentiation.
• 1965- Lauren- Intestinal, Diffuse types.
• 1990- WHO- Adeno Ca., AdenoSq.,
SqCC, Small cell Ca., Undifferentiated Ca.

12. Lauren’s
• Differentiated Undifferentiated

13. Japanese macroscopic
classifications (Endoscopic)
In the combined superficial types, the type occupying the largest
area should be described first, followed by the next type.

14. • 0-I
• 0-II
• 0-III

15. Carcinoma- Pathological
• Western countries- if the tumor has invaded the
submucosa or muscularis mucosae, at least
deeper than the lamina propria.
• Japan- based on cellular atypia or structural
atypia, regardless of the extent of invasion.
• Vienna classification was proposed to lessen
this discripency.

16. Vienna classification
of gastrointestinal epithelial neoplasia
Category 1 Negative for neoplasia/dysplasia
Category 2 Indefinite for neoplasia/dysplasia
Category 3 Non-invasive low grade neoplasia (low
grade adenoma/dysplasia)
Category 4 Non-invasive high grade neoplasia
4.1 High grade adenoma/dysplasia
4.2 Non-invasive carcinoma (carcinoma in situ)*
4.3 Suspicion of invasive carcinoma
Category 5 Invasive neoplasia
5.1 Intramucosal carcinoma†
5.2 Submucosal carcinoma or beyond

17. Japanese Gastric Cancer
Association Staging System
• CECT- the
modality of
choice for
staging of
gastric cancer.
• Sensitivity to
determine
nodal status -
50% to 95%
• Specificity -
40% to 99%.

18. LN stations

19. Endoscopic Diagnosis
• White light endoscopy,
• Chromoendoscopy,
• Narrow band imaging (NBI),
• Endoscopic ultrasonography (EUS)

20. White Light Endoscopy
• Slight color changes in the mucosa (pale
redness or fading of color),
• Loss of visibility of underlying submucosal
vessels,
• Thinning of and interruptions in mucosal
folds,
• Spontaneous bleeding.

21. Chromoendoscopy
• Dye-based image-enhanced endoscopy
• 0.2- 0.4% indigo carmine
– highlights subtle differences in elevation of the
mucosal surface
– changes in color.
• Magnifying chromoendoscopy (x80):
– surface mucosal pattern
– capillary structure

22. Chromoendoscopy

23. Narrow Band Imaging
• Equipment-based image-enhanced
endoscopy.
• illuminating blue and green narrowband lights
– irregular microvascular pattern (MV)
– absence of a microsurface pattern (MS)
1. Differentiate small gastric cancer (<1cm)
from gastritis.
2. Improve margin determination capabilities
for endoscopic therapy.

24. NBI
Differentiated Carcinoma Undifferentiated Carcinoma

26. Endoscopic
Ultrasonography (EUS)
• 20 MHz catheter-based miniprobes- High
frequency (instead of 12 Mhz)
• diagnosing invasion depth
• preoperatively to assess the submucosal
vasculature in order to predict
intraoperative bleeding

27. EUS

28. Endoscopic Therapy
• The frequency of LN metastasis in EGC:
– 3% for intramucosal carcinoma
–20% for submucosal carcinoma
• Indications:
–Lesions where lymph node metastasis can be
disregarded

29. Endoscopic Therapy
• Strip biopsy method (two-channel
method)- 1984.
• EMR (Endoscopic Mucosal Repair)
–Endoscopic Resection With A Cap-fitted
Panendoscope (EMRC)
• ESD (Endoscopic Submucosal Dissection)

30. Indications
• a differentiated elevated intramucosal
cancer <2 cm in size
• a differentiated depressed intramucosal
cancer <1 cm in size without ulcer findings

31. EMR
• Initially:
– injecting saline under the lesion thus raising
the tissue and allowing it to be grasped for
snaring
• Later:
– different injection solutions- hypertonic saline
with dilute epinephrine,
–addition of cap-fitted panendoscopes,
– variceal ligation devices to capture the lesions

32. EMR

33. EMR- Strip biopsy
•

34. EMR
Disadvantage:
• Large tumors (>1.5cm) which cannot be
resected en bloc are removed piecemeal
which makes difficult to assess completion
and curability of the resection by
histopathology and increases the
incidence of residual tumor.

35. ESD
• dissecting along the submucosal layer directly
using a high-frequency knife
• Indications:
– differentiated intramucosal cancers without ulcer
findings, irrespective of tumor size,
– differentiated intramucosal cancers less than 3 cm in
size with ulcer
– differentiated minute invasive submucosal SM1 (less
than 500 μm below the muscularis mucosa) cancers
less than 3 cm
– undifferentiated intramucosal cancers less than 2 cm
in size without ulcer

36. Rate of LN metastasis

37. Procedure selection

38. ESD

39. ESD- procedure
•

40. ESD
• Disadvantage:
– increased instances of perforation or bleeding
• can be treated with endoscopy

41. Management, Surveillance
Postendoscopic Resection
• EMR: annual endoscopic surveillance to ensure
early detection of metachronous cancer (5.9%)
• ESD: annual endoscopic surveillance + half-yearly
abdominal computed tomography or
endoscopic ultrasonography, for at least 3 years
in order to detect lymph node or distant
metastasis.

42. Procedure selection

43. Limited surgical resection
• Gastrotomy with full-thickness mural
excision (to allow accurate pathologic
assessment of T status)
• Aided by intraoperative gastroscopy for
tumor localization.
• Formal lymph node dissection is not
required in these patients.

44. Gastrectomy
• Lower, upper or total gastrectomy with D1
or D2 LN dissection.

45. Future prospects
• Laparoscopy-assisted ESD
• Full-thickness resection of the stomach
• Full-layer resection for gastric cancer with
non-exposure technique (CLEAN-NET)
• Sentinel LN Biopsy
• NOTES
• SILS

46. Bibliography
• Sabiston Textbook of Surgery- 18th Edition
• DeVita- Cancer- Principles and Practice of
Oncology 8th edition
• Diagnostic and Therapeutic Endoscopy, Volume
2013, Article ID 241320
• www.surgicaloncology.net
• Annals of gastroenterology, vol 25, no. 4, 2012
• Gastroenterology, 2011
• BMC Gastroenterology, 2011

47. Thank You