Udom Kachintorn

Screening for gastric cancer in Asia: current evidence and practice

Gastric cancer is the second most common cause of death from cancer in Asia. Although surgery is the standard treatment for this disease, early detection and treatment is the only way to reduce mortality. This Review summarises the epidemiology of gastric cancer, and the evidence for, and current practices of, screening in Asia. Few Asian countries have implemented a national screening programme for gastric cancer; most have adopted opportunistic screening of high-risk individuals only. Although screening by endoscopy seems to be the most accurate method for detection of gastric cancer, the availability of endoscopic instruments and expertise for mass screening remains questionable--even in developed countries such as Japan. Therefore, barium studies or serum-pepsinogen testing are sometimes used as the initial screening tool in some countries, and patients with abnormal results are screened by endoscopy. Despite the strong link between infection with Helicobacter pylori and gastric cancer, more data are needed to define the role of its eradication in the prevention of gastric cancer in Asia. At present, there is a paucity of quality data from Asia to lend support for screening for gastric cancer.

Second Asia–Pacific Consensus Guidelines for Helicobacter pylori infection

The Asia–Pacific Consensus Conference was convened to review and synthesize the most current information on Helicobacter pylori management so as to update the previously published regional guidelines. The group recognized that in addition to long‐established indications, such as peptic ulcer disease, early mucosa‐associated lymphoid tissue (MALT) type lymphoma and family history of gastric cancer, H. pylori eradication was also indicated for H. pylori infected patients with functional dyspepsia, in those receiving long‐term maintenance proton pump inhibitor (PPI) for gastroesophageal reflux disease, and in cases of unexplained iron deficiency anemia or idiopathic thrombocytopenic purpura. In addition, a population ‘test and treat’ strategy for H. pylori infection in communities with high incidence of gastric cancer was considered to be an effective strategy for gastric cancer prevention. It was recommended that H. pylori infection should be tested for and eradicated prior to long‐term aspirin or non‐steroidal anti‐inflammatory drug therapy in patients at high risk for ulcers and ulcer‐related complications. In Asia, the currently recommended first‐line therapy for H. pylori infection is PPI‐based triple therapy with amoxicillin/metronidazole and clarithromycin for 7 days, while bismuth‐based quadruple therapy is an effective alternative. There appears to be an increasing rate of resistance to clarithromycin and metronidazole in parts of Asia, leading to reduced efficacy of PPI‐based triple therapy. There are insufficient data to recommend sequential therapy as an alternative first‐line therapy in Asia. Salvage therapies that can be used include: (i) standard triple therapy that has not been previously used; (ii) bismuth‐based quadruple therapy; (iii) levofloxacin‐based triple therapy; and (iv) rifabutin‐based triple therapy. Both CYP2C19 genetic polymorphisms and cigarette smoking can influence future H. pylori eradication rates.

Epidemiology of uninvestigated and functional dyspepsia in Asia: facts and fiction.

Dyspepsia is a syndrome consisting of epigastric pain, burning, fullness, discomfort, early satiety, nausea, vomiting and belching. Functional dyspepsia (FD) is diagnosed if upper gastrointestinal endoscopy does not show structural abnormality explaining these symptoms. 8%-30% and 8%-23% of Asian people suffer from of uninvestigated dyspepsia and FD, respectively. Most patients with uninvestigated dyspepsia are found to have FD. Patients with FD are usually young and there is no predilection to any gender. Overlap of FD with other functional bowel diseases such as irritable bowel syndrome and gastroesophageal reflux disease is common in Asia. Cultural difference in reporting of symptoms of dyspepsia is well-known. Moreover, dietary factors, socio-cultural and psychological issues, gastrointestinal infection including that caused by Helicobacter pylori, frequency of organic diseases such as peptic ulcer and gastric cancer responsible for dyspeptic symptoms in the study population may also influence epidemiology of dyspepsia. There is considerable heterogeneity in the above issues among different Asian countries. More studies on epidemiology of FD are needed in Asia.

Asian Consensus Report on Functional Dyspepsia

Background/Aims Environmental factors such as food, lifestyle and prevalence of Helicobacter pylori infection are widely different in Asian countries compared to the West, and physiological functions and genetic factors of Asians may also be different from those of Westerners. Establishing an Asian consensus for functional dyspepsia is crucial in order to attract attention to such data from Asian countries, to articulate the experience and views of Asian experts, and to provide a relevant guide on management of functional dyspepsia for primary care physicians working in Asia. Methods Consensus team members were selected from Asian experts and consensus development was carried out using a modified Delphi method. Consensus teams collected published papers on functional dyspepsia especially from Asia and developed candidate consensus statements based on the generated clinical questions. At the first face-to-face meeting, each statement was reviewed and e-mail voting was done twice. At the second face-to-face meeting, final voting on each statement was done using keypad voting system. A grade of evidence and a strength of recommendation were applied to each statement according to the method of the GRADE Working Group. Results Twenty-nine consensus statements were finalized, including 7 for definition and diagnosis, 5 for epidemiology, 9 for pathophysiology and 8 for management. Algorithms for diagnosis and management of functional dyspepsia were added. Conclusions This consensus developed by Asian experts shows distinctive features of functional dyspepsia in Asia and will provide a guide to the diagnosis and management of functional dyspepsia for Asian primary care physicians.

Comparison of Prevention of NSAID-Induced Gastrointestinal Complications by Rebamipide and Misoprostol: A Randomized, Multicenter, Controlled Trial—STORM STUDY

Nonsteroidal anti-inflammatory drugs (NSAIDs) have gastrointestinal side effects such as dyspepsia, peptic ulcer, hemorrhage, and perforation. Misoprostol and PPIs have been used to prevent NSAID-induced gastroduodenal injury. Rebamipide increases gastric mucus and stimulates the production of endogenous prostaglandins. The prophylactic effect of rebamipide on NSAID-induced gastrointestinal complications is unknown. The aim of this study was to compare NSAID-induced gastrointestinal complications in rebamipide- and misoprostol-treated groups. Patients were randomized to two groups and took a conventional NSAID plus rebamipide or misoprostol for 12 weeks. Gastric mucosal damage was evaluated by endoscopy at screening and the end of the study. The prevalences of active gastric ulcer were 7/176 (3.9%) in the rebamipide group and 3/156 (1.9%) in the misoprostol group. The prevalences of peptic ulcer were 8/176 (4.5%) in the rebamipide group and 7/156 (4.4%) in the misoprostol group. The cumulative incidences of peptic ulcer in the high-risk subgroup were 6/151 (4.0%) for rebamipide and 6/154 (3.9%) for misoprostol. In conclusion, rebamipide prevented NSAID-induced peptic ulcer as effectively as misoprostol in patients on long-term NSAID therapy. Rebamipide may be a useful therapeutic option for the prevention of NSAID-induced gastrointestinal ulcer because of its therapeutic effect and safety.

Clofazimine-induced crystal-storing histiocytosis producing chronic abdominal pain in a leprosy patient.

Clofazimine-induced crystal-storing histiocytosis is a rare but well-recognized condition in the literature. Besides the common reddish discoloration of the skin, clofazimine produces gastrointestinal disturbances-sometimes severe abdominal pain, prompting exploratory laparotomy, because pathologic and radiologic findings can produce diagnostic difficulties if the pathologic changes caused by clofazimine are not recognized. The authors report such a case in a leprosy patient to emphasize the importance of history taking, the radiologic abnormalities of the small intestine, and the pathologic findings in small intestine and lymph node biopsies. Clofazimine crystals are red in the frozen section and exhibit bright-red birefringence. However, they are clear in routinely processed histologic sections because they dissolve in alcohol and organic solvents. They also appear as clear crystal spaces during electron microscopic study, but some osmiophilic bodies can be observed. Histiocytosis caused by clofazimine crystals produces infiltrative lesions in radiologic studies mimicking malignant lymphoma or other infiltrative disorders. Associated plasmacytosis in the histologic sections can simulate lymphoplasmacytic lymphoma or multiple myeloma with crystal-storing histiocytosis. With the knowledge of this rare condition caused by clofazimine, appropriate management to avoid an unnecessary laparotomy is possible.

Asian consensus report on functional dyspepsia

Background and Aim:  Environmental factors such as food, lifestyle and prevalence of Helicobacter pylori infection are widely different in Asian countries compared with the West, and physiological functions and genetic factors of Asians may also be different from those of Westerners. Establishing an Asian consensus for functional dyspepsia is crucial in order to attract attention to such data from Asian countries, to articulate the experience and views of Asian experts, and to provide a relevant guide on management of functional dyspepsia for primary care physicians working in Asia.

A 2008 Questionnaire-Based Survey of Gastroesophageal Reflux Disease and Related Diseases by Physicians in East Asian Countries

Background/Aims: Gastroesophageal reflux disease (GERD) is a common gastrointestinal disease. This study was designed to examine current epidemiology, diagnosis, management, and treatment of patients diagnosed with GERD by surveying physicians in several East Asian countries. Methods: A questionnaire-based survey was completed in six countries including China, Indonesia, Japan, Korea, the Philippines, and Thailand between July 2008 and December 2008. Results: In total, 876 physicians participated in the study. Most physicians in all countries, except Japan, frequently used international guidelines for the care of GERD patients, whereas approximately half of Japanese physicians did not use such guidelines. GERD was common among many patients, but Barrett’s esophagus, particularly the long-segmental type, was rare. The incidence of esophageal cancer, particularly adenocarcinoma, was high in China, but low in other countries. Most physicians diagnosed GERD based on symptoms, followed by endoscopy in Japan and Korea, or in other countries, by the proton-pump inhibitor (PPI) test. Heartburn was recognized as the chief complaint in all countries except Korea. Most physicians in all countries used PPI as the first-line of treatment for GERD. Increasing the PPI dose was the treatment of choice for PPI-refractory erosive esophagitis in Korea, the Philippines, and Thailand. In contrast, in other countries, physicians used a combination of PPI and other drugs to treat PPI-refractory erosive esophagitis. Prescription of antidepressant drugs increased for PPI-refractory nonerosive reflux disease compared with PPI-refractory erosive esophagitis. Conclusion: The findings in the present survey are useful to understand the current epidemiology, diagnosis, and treatment of GERD in East Asian countries.

A questionnaire-based survey on the prescription of non-steroidal anti-inflammatory drugs by physicians in East Asian countries in 2007.

Background: Nonsteroidal anti-inflammatory drugs (NSAIDs) and aspirin are widely used clinically but increase the risk of gastrointestinal (GI) complications. Aim: To examine the current prescription of NSAIDs and comedication to prevent GI complications from NSAIDs within East Asia by means of a questionnaire survey. Methods: Representative members of the Committee of the International Gastrointestinal Consensus Symposium provided a questionnaire to physicians in 6 East Asian countries. Results: A total of 1,568 physicians participated in this survey. Most physicians prescribed nonselective NSAIDs, cyclooxygenase-2 inhibitors (COXIBs) or aspirin for more than 5 patients per week in all countries, with the exception of the prescription of COXIBs in Japan. Of the nonselective NSAIDs, the drug most frequently prescribed as a first choice was loxoprofen (34%), which was mainly prescribed in Japan, followed by diclofenac (30%). The frequency of prescription of comedication with nonselective NSAIDs was higher compared with that for selective COXIBs or aspirin. Physicians in the northern region (China, Japan and Korea) preferred mucoprotective drugs for comedication with NSAIDs or aspirin, while those in southern region (Indonesia, Philippines and Thailand) frequently used proton-pump inhibitors. Conclusion: Among East Asian countries, there are both similarities and differences in the prescription of NSAIDs and of comedication to prevent GI complications.

Normal Solid Gastric Emptying Values Measured by Scintigraphy Using Asian-style Meal:A Multicenter Study in Healthy Volunteers.

Background/Aims To report gastric emptying scintigraphy, normal values should be established for a specific protocol. The aim of this study was to provide normal gastric emptying values and determine factors affecting gastric emptying using Asian rice-based meal in healthy volunteers. Methods One hundred and ninety-two healthy volunteers were included at 7 tertiary care centers across Thailand. Gastric emptying scintigraphy was acquired in 45 degree left anterior oblique view immediately after ingestion of a 267 kcal steamed-rice with technetium-99m labeled-microwaved egg meal with 100 mL water for up to 4 hours. Results One hundred and eighty-nine volunteers (99 females, age 43 ± 14 years) completed the study. The medians (5–95th percentiles) of lag time, gastric emptying half time (GE T1/2) and percent gastric retentions at 2 and 4 hours for all volunteers were 18.6 (0.5–39.1) minutes, 68.7 (45.1–107.8) minutes, 16.3% (2.7–49.8%) and 1.1% (0.2–8.8%), respectively. Female volunteers had significantly slower gastric emptying compared to male (GE T1/2, 74 [48–115] minutes vs. 63 (41–96) minutes; P < 0.05). Female volunteers who were in luteal phase of menstrual cycle had significantly slower gastric emptying compared to those in follicular phase or menopausal status (GE T1/2, 85 [66–102] mintes vs. 69 [50–120] minutes or 72 [47–109] minutes, P < 0.05). All of smoking volunteers were male. Smoker male volunteers had significantly faster gastric emptying compared to non-smoker males (GE T1/2, 56 [44–80] minutes vs. 67 [44–100] minutes, P < 0.05). Age, body mass index and alcohol consumption habits did not affect gastric emptying values. Conclusions A steamed-rice with microwaved egg meal was well tolerated by healthy volunteers. Gender, menstrual status and smoking status were found to affect solid gastric emptying.