Gastric cancer (GCa) has a significant impact on worldwide morbidity and mortality as the third-leading cause of cancer death in the world.1 It has traditionally been associated with poor outcomes and limited treatment options by the time patients clinically present. Helicobacter pylori (HP) is the primary cause of intestinal-type noncardia GCa (located in the antrum, body, incisura, or fundus).2 Intestinal-type cancer has been shown to progress through several stages before adenocarcinoma: nonatrophic gastritis, atrophic gastritis, intestinal metaplasia, and then subsequently gastric adenocarcinoma.3 

Gastric intestinal metaplasia (GIM) is frequently encountered by gastroenterologists who perform upper endoscopy, and up until recently, there has been a lack of guidance on how to appropriately follow these patients. According to one study conducted by Altayar et al, the pooled prevalence of GIM in 897,371 patients with gastric biopsies was 4.8% (95% CI, 4.8%-4.9%).4 Importantly, the American Gastroenterological Association (AGA) recently published new clinical practice guidelines in Gastroenterology on the management of GIM in an attempt to answer many of the frequently encountered questions revolving around GIM.5 

The new AGA guidelines make recommendations that should be considered when encountering GIM. Patients with GIM are recommended to be tested for H pylori and, if positive, treated with subsequent confirmation of eradication.  This is based on several studies showing eradication of H pylori in patients with GIM has led to a reduced risk for incident GCa. H pylori has become increasingly challenging to treat; therefore, it is important to review the most updated guidelines and resistance patterns available. 

With respect to surveillance, the AGA recommends against the routine use of endoscopic surveillance, unless the patient has potential for a higher risk of developing GCa. This is based on the relatively low risk of developing GCa from GIM, approximated at 0.16% annually and a 1.6% cumulative risk over 10 years. Patients with GIM at higher risk (≥1.6%/10 y) of developing GCa can be considered for surveillance; however, this should be a “shared decision” between the patient and physician. These patients include individuals with incomplete GIM, extensive GIM, and family history of GCa. In addition, racial and ethnic minorities and immigrants from high incidence groups (eg, Japan and Korea) should also be considered for surveillance. The guidelines state that if surveillance is chosen, there is insufficient evidence to recommend a formal interval, although an every 3- to 5-year interval has been reported in the literature.


Continue Reading

Related Articles

The AGA’s final recommendation was against the short-interval repeat endoscopy in patients diagnosed with GIM for the purpose of risk stratification; however, a repeat endoscopy within 1 year of the initial endoscopy could be considered if a patient is considered high risk for GCa (as detailed earlier), if there is high-risk endoscopic stigmata (eg, nodularity), and/or if there is concern about the completeness of the baseline endoscopy. The recommendation against routine short-interval repeat endoscopy (within 1 year) is at least partially based on the cumulative incidence of GCa within 1 year of GIM diagnosis to be approximately 0.5% (95% CI, 0.4%-0.6%).6

The AGA guidelines are similar to the other currently available GIM guidelines. The American Society of Gastroenterology Endoscopy guidelines from 2015 similarly recommend surveillance endoscopy in patients with GIM at increased risk for GCa based on family history or ethnic background, although a formal interval was also not able to be provided based on the available evidence.7 The European Society of Gastrointestinal Endoscopy guidelines published in 2019 recommended a surveillance endoscopy 3 years from the baseline scope in patients with increased risk for GCa but otherwise not for “routine” cases of GIM.8

These guidelines are a helpful update for gastroenterologists; however, additional data will need to be collected and incorporated in the future. The guidelines frequently still note a paucity of data regarding the management of GIM, which is reflected in the “very low” and “moderate” quality of evidence listed to support the AGA recommendations. The authors emphasized “shared decision making” with patients in all instances, which is important to document in patients’ charts. The authors plan to update these guidelines no later than 2022.  

Follow @Gastro_Advisor

References

1. Bray F, Ferlay J, Soerjomataram I, Siegel RL, Torre LA, Jemal A. Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin. 2018;68(6):394-424.

2. Plummer M, Franceschi S, Vignat J, Forman D, de Martel C. Global burden of gastric cancer attributable to Helicobacter pylori. Int J Cancer. 2014;136(2):487-490.

3. Correa P. Gastric cancer: overview. Gastroenterol Clin North Am. 2013;42(2):211-217.

4. Altayar O, Davitkov P, Shah SC, et al. AGA technical review on gastric intestinal metaplasia—epidemiology and risk factors. Gastroenterology. 2020;158(3):732-744.

5. Gupta S et al. AGA clinical practice guidelines on management of gastric intestinal metaplasia. Gastroenterology. 2020;158(3):693-702.

6. Gawron AJ, Shah SC, Altayar O, et al. AGA technical review on gastric intestinal metaplasia—natural history and clinical outcomes. Gastroenterology. 2020;158(3):705-731.

7. ASGE Standards of Practice Committee, Evans JA, Chandrasekhara V, et al. The role of endoscopy in the management of premalignant and malignant conditions of the stomach. Gastrointest Endosc. 2015;82(1):1-8.

8. Pimentel-Nunes P, Libanio D, Marcos-Pinto R, et al. Management of epithelial precancerous conditions and lesions in the stomach (MAPS II): European Society of Gastrointestinal Endoscopy (ESGE), European Helicobacter and Microbiota Study Group (EHMSG), European Society of Pathology (ESP), and Sociedade Portuguesa de Endoscopia Digestiva (SPED) guideline update 2019. Endoscopy. 2019;51(4):365-388.