Because of the low incidence of gastric cancer in the United States , endoscopic screening is not currently recommended . Because endoscopic resection techniques , such as endoscopic submucosal dissection , are becoming increasingly available in the United States , many EGCs can be endoscopically resected without the need for surgery . Given these developments , a change in our approach to managing individuals at high risk for developing gastric cancer is needed along with the establishment of a screening and surveillance protocol for high-risk individuals .
The new national guidelines in Japan now recommend that screening start at age 50 . A study evaluating the cost-effectiveness of screening the general population for upper GI ( UGI ) cancers , including EGC in the United States , by performing an upper endoscopy at the time of a screening colonoscopy showed that the incremental costeffectiveness ratio for this intervention was �95,559 per quality-adjusted life year saved ; this is comparable with published incremental cost effectiveness ratios for other cancer screening interventions that are commonly performed in the United States . Therefore , a screening programme targeting a smaller highrisk population should be substantially more costeffective .
Screening for gastric cancer generally involves 4 methods : upper gastrointestinal series , serum pepsinogen ( PG ) testing , H pylori serology , and endoscopy . Endoscopy is the only method available for direct visual examination of the gastric mucosa , and it allows for biopsy sampling so that microscopic evaluation can be performed . Endoscopy is the criterion standard test for diagnosing gastric cancer because of its high detection rate . In Japan and Korea , endoscopy has become the primary method for gastric cancer screening given its superior test characteristics , availability , and affordability . However , the use of endoscopy for gastric cancer screening in the United States does have several potential limitations , such as the need for additional trained endoscopists to meet the increased demand , potential adverse events of endoscopy , patient acceptance , and cost .
Data from Japan and Korea support the effectiveness of screening for gastric cancer in high-risk populations . Screening every two years decreased the incidence of gastric cancer and showed that endoscopic resection could be applied to more patients who underwent EGD screening within two years . A European review article proposed that annual endoscopic surveillance would appear justified in all patients with intestinal metaplasia of incomplete type . The 2015 American Society for Gastrointestinal Endoscopy guidelines suggest that surveillance endoscopy be performed in patients with gastric intestinal metaplasia who are at an increased risk of gastric cancer because of their ethnic background or family history and that surveillance intervals should be individualised .
Japan and Korea have high incidence of the disease
In Singapore , a new blood test is now being performed to screen individuals for gastric cancer . This is a miRNA-based biomarker ( Gastroclear ) which groups individuals into low , medium , and high risk of having or subsequently developing gastric cancer . This test can be used to determine initial screening and subsequent surveillance endoscopies and intervals . It has been shown to have higher sensitivity compared to other tests for screening gastric cancer and seems to have great potential after further validation .
What all this means is that comprehensive guidelines for gastric cancer screening and surveillance of high-risk individuals continue to be warranted . The optimal gastric cancer prevention programme should combine risk stratification for screening and surveillance for high-risk groups . Because race , H pylori infection , family history of gastric cancer , and atrophic gastritis / intestinal metaplasia are significant risk factors for gastric cancer , the initial approach should be to identify individuals with these risk factors . It would also be reasonable to begin screening individuals who are at high risk for developing gastric cancer and then perform surveillance endoscopy at one- or two-year intervals if IM is identified on screening endoscopy or if the patient has a family history of gastric cancer . Gastric cancer screening in the appropriate population will likely lead to an increase in the detection of EGCs , which may improve the likelihood of being able to intervene with endoscopic therapy , such as endoscopic submucosal dissection , and reduce mortality from gastric cancer . n
Dr Jaideep Raj Rao is the senior consultant surgeon at JR surgery at Mount Elizabeth Novena Hospital , Singapore . He ’ s a specialist in minimally invasive and robotic surgery , oncology surgery , bariatric and metabolic surgery , gastrointestinal surgery , and hernia and complex abdominal wall reconstruction .
GlobalHealthAndTravel . com AUGUST 2021
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