Background and Rationale:
Gastric cancer is the second leading cause of cancer related death in the world in recently
data. The incidence and mortality rate is predominant in East Asia. Usually, gastric cancer
is asymptomatic in early stage; therefore; most patients is in the advanced stage and
incurable at diagnosis. The pathogenesis of intestinal type gastric cancer is sequential and
multistep pathway. Moreover, the direction of pathway is irreversible beyond dysplasia. The
equipment and/or procedure which can detect gastric dysplasia are very beneficial.
The recent study, Imraporn B et al., showed that narrow-banded imaging with magnification
(NBI-ME) had a better sensitivity for gastric intestinal metaplasia (GIM) detection than a
standard white light endoscopy (73% VS. 13%) and could detect two early gastric cancer from
tissue pathology in 1-year follow-up cohort study. However, NBI-ME cannot differentiate
among GIM, dysplasia and gastric cancer.
Confocal endomicroscope is a powerful instrument for performing high-resolution (x1,000
time) imaging to enable real-time histology and/or optical biopsy at the time of endoscopic
examination(in vivo histology).Fluorescein, is a slightly acidic and hydrophilic dye, will
be used as staining substance via IV administration. The fluorescein established a stable
distribution throughout surface epithelial cells, which is regular columnar epithelium with
round gland openings and cobblestone pattern; the connective tissue matrix of lamina
propria; blood vessels, which are regular shape visible in the deeper mucosa; and red blood
cells.It is not highly miscible with mucins, hence, mucins in goblet cells, which indicated
GIM, will appear dark.
Because GIM is characterized by the diminutive lesions or microscopic abnormalities amidst
large fields of diffuse disease, biopsy targeting and adequate sampling can be difficult and
time consuming. Therefore, the instant resection with confocal microendoscope is not
Consequently, the patient must be diagnosed GIM via a targeted NBI-ME biopsy first. And then
endoscopic mucosal resection (EMR) via confocal endomicrosocpe is possible to be the
complete therapeutic treatment for early gastric cancer within the same session at the
suspected area of gastric dysplasia or neoplasia.
However, no study about confocal endomicroscope related early detection of gastric cancer
In this study, we must apply the endomicroscope's criteria from confocal Barrett's esophagus
classification to indicate gastric dysplasia or neoplasia. The aim of this study is to
evaluate the feasibility of confocal endomicroscopy to diagnose gastric intestinal
Review of related literature:
Confocal endomicroscope is available in 2005. The difference between white light endoscope
and confocal endomicroscope.
Nowadays, a point-scanning fiber-optic fluorescein confocal endomicroscope for evaluate
cellular morphology of the upper- and the lower-GI tract is possible. However, the
improvement of diagnostic yield is evaluated in only Barrett's esophagus, colorectal cancer,
detecting Helicobacter pylori. There is no exactly study about early detection of gastric
cancer with confocal endomicroscope. Investigator use the confocal Barrett's esophagus
classification to predict the area of dysplasia or neoplasia in stomach.
All patients have to undergo a targeted NBI-ME biopsy and never be treated as gastric cancer
Confocal endomicroscope Gastric intestinal metaplasia
Gastric intestinal metaplasia/dysplasia/neoplasim is base on the updated Sydney
Population and Sample Target and sample population: The patients who were diagnosed gastric
intestinal metaplasia (GIM) in the past 2 years in KCMH.
Observation and Measurement:
Collect the geographic data by interview and review the outpatient record. Evaluate the
tissue pathology by one pathologist
1. All patients had informed the consent.
2. Take the history, physical examination and then fill in the record form
3. Set confocal endomicroscopy
- 10% Fluorescein sodium 10 ml was injected intravenously.
- 2.5-5 milligrams of intravenous midazolam and 10 milligrams of hyoscine were
injected to sedate and decrease bowel movement for easier and complete
- Simethicone solution was rinsed to reduce mucous and gas bubble in the stomach.
- FICE was used to identify the area of suspected GIM.
- Confocal endomicroscopy was performed and targeted to the suspected area. One
snapshot images was recorded at the area of suspected and record the criteria of
diagnosis GIM. Endoscopic resection was done at the suspected area.
- DVD was recorded during the endoscopy.
4. Record the duration and complication of the procedure
5. Send the tissues to one clinically-blinded GI pathologist
6. Compare the pathology report and endoscopic finding
7. Report the result
All data are processed and recorded by one physician.
There is not a clearly evidence about the serious side effect of fluorescein injection. If
the patients had side effects during the research, the procedure will be terminated and the
patients will be take care from KCMH staff.
This is a novel diagnostic tool to analyze living cells during endoscopy, especially for
gastric intestinal metaplasia (GIM). There is not a standard criterion about confocal
endomicroscopy finding in GIM. Investigator have to apply from Barrett's esophagus criteria
and learn about criteria in GIM and gastric cancer.
Obstacles and strategies to solve the problems:
Because this is the study which base on the population from previous study by Imraporn et
al., maybe some patients will loss follow up. The strategies to solve the problems are
1. Early call back to make an appointment
2. Collect new patients from the database of pathology department, KCMH
Allocation: Non-Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Diagnostic
The feasibility of confocal endomicroscope in diagnose gastric intestinal metaplasia
If GIM can be detected properly, early gastric cancer(EGC) will be in early recognition. EGC can be cured by endoscopic resection and then the mortality rate from gastric cancer will be decrease.
Up to 2 years
Thailand: Ethical Committee