Clinical Impact of Different Reconstruction Methods on Remnant Gastric Cancer at the Anastomotic Site after Distal Gastrectomy

Background/Aims

The anastomotic site after distal gastrectomy is the area most affected by duodenogastric reflux. Different reconstruction methods may affect the lesion characteristics and treatment outcomes of remnant gastric cancers at the anastomotic site. We retrospectively investigated the clinicopathologic and endoscopic submucosal dissection outcomes of remnant gastric cancers at the anastomotic site.

Methods

We recruited 34 consecutive patients who underwent endoscopic submucosal dissection for remnant gastric cancer at the anastomotic site after distal gastrectomy. Clinicopathology and treatment outcomes were compared between the Billroth II and non-Billroth II groups.

Results

The tumor size in the Billroth II group was significantly larger than that in the non-Billroth II group (22 vs. 19 mm; p=0.048). More severe gastritis was detected endoscopically in the Billroth II group (2 vs. 1.33; p=0.0075). Moreover, operation time was longer (238 vs. 121 min; p=0.004) and the frequency of bleeding episodes was higher (7.5 vs. 3.1; p=0.014) in the Billroth II group.

Conclusions

Compared to remnant gastric cancers in non-Billroth II patients, those in the Billroth II group had larger lesions with a background of severe remnant gastritis. Endoscopic submucosal dissection for remnant gastric cancers in Billroth II patients involved longer operative times and more frequent bleeding episodes than that in patients without Billroth II.

The Relationship between Primary Duodenogastric Reflux and Helicobacter pylori Gastritis in Children

BACKGROUND

Most studies of the relationship between duodenogastric reflux (DGR) and Helicobacter pylori have reported that the presence of DGR decreases H. pylori colonization, while H. pylori infection increases the frequency of DGR by impairing antroduodenal motility. The present study aimed to investigate the relationship between primary DGR and the prevalence of H. pylori in children, as well as the degree of colonization and the presence and severity of gastritis.

METHODS

Included in the study were 410 patients between the ages of 2 and 18 years, referred to the pediatric gastroenterology clinic with complaints of dyspepsia, abdominal pain, and nausea/vomiting, who underwent upper gastrointestinal system endoscopic examination and stomach biopsy. The study group included 60 patients with DGR, while 350 non-DGR patients formed the control group.

RESULTS

The mean age of patients with DGR was 15.7 ± 2.1 years, while the mean age of the control group was 14.2 ± 3.8 years (p = 0.02). Of those with DGR, 50 (83.3%) were girls, while in the control group, 215 (61.4%) were girls (p = 0.001). Of patients with DGR, 16 were H. pylori (+) (26.7%), while in the control group, 168 were H. pylori (+) (48%) (p = 0.002). There was no significant difference between the 2 groups with respect to H. pylori degree of colonization (p = 0.08). Gastritis was present in 56 (93.3%) patients in the DGR group and 322 (92%) patients in the control group (p = 0.72). A significant difference was found between the 2 groups in terms of gastritis severity (p = 0.01).

CONCLUSIONS

The mean age of patients with DGR was significantly higher than that of patients without DGR, and DGR was found to be more common in girls. In patients with DGR, H. pylori prevalence was significantly lower than in those without DGR; however, no significant difference was found between the 2 groups with respect to the colonization degree.

Development and characterization of a mouse model of duodenogastric reflux

AIMS

Rat models of duodenogastric reflux have been used to study gastric stump cancer (GSC), but the underlying molecular mechanisms are poorly understood. Unlike rats, mice can be genetically modified, providing a superior model for studying the molecular mechanisms underlying GSC development, which is associated with duodenogastric reflux. This study aimed at developing a mouse model of duodenogastric reflux.

MAIN METHOD

C57BL/6 mice were randomly assigned to the control (n = 6), sham operation (n = 9), or gastrojejunostomy group (n = 12). Mice were sacrificed at 1, 3, and 6 months after surgery. Stomach tissue was stained with hematoxylin and eosin. Lesions were classified as chronic inflammation, intestinal metaplasia, or atypical hyperplasia.

KEY FINDINGS

Nine mice underwent gastrojejunostomy without mortality. The animals in the gastrojejunostomy group exhibited chronic inflammation at 1, 3, and 6 months after surgery, showing intestinal metaplasia (n = 2) and atypical hyperplasia (n = 1) at 3 months and intestinal metaplasia (n = 2) and atypical hyperplasia (n = 2) at 6 months. The mice in the control group did not exhibit chronic inflammation or intestinal metaplasia, whereas those in the sham operation group exhibited chronic inflammation at 1, 3, and 6 months after surgery, without intestinal metaplasia or atypical hyperplasia. Intestinal metaplasia or atypical hyperplasia were more common in the gastrojejunostomy group than in the sham operation group (p = 0.012).

SIGNIFICANCE

A duodenogastric reflux mouse model can be created using gastrojejunostomy without gastrectomy.

Theoretical modeling of the resistance to gastric emptying and duodenogastric reflux due to pyloric motility alone, presuming antral and duodenal quiescence

A theoretical model of the pyloric channel, approximated as a two-dimensional tube with sinusoidal corrugation, is developed to estimate the degree of resistance offered by the pylorus to transpyloric flow (gastric emptying and duodenogastric reflux) in the viscous regime. Study indicates that the resistance of the channel depends on pressure gradient, flow behavior index and channel diameter. Flow is majorly determined by the extent of luminal opening; since they scale to fourth power of the diameter for Newtonian flow, with the exponent being higher for pseudoplastic and lesser in case of dilatants relative to Newtonian fluid. At zero pressure difference, across the channel, the closing pylorus drives the aborad propulsion of the contents at the intestinal end, and at the gastric end the flow is driven along the orad direction. While no transfer of contents occur at the centre of pylorus due to zero pressure gradients, it is essential to have a non-zero pressure difference to drive the flow through the channel. The extent of pressure difference is found to linearly relate to the transpyloric flow rate. The resistive function of the pyloric channel is observed at a higher occlusion where there is a development of higher pressure barrier that is sensitive to the flow behavior index, frequency, occlusion, and contraction length.

Durable Flap-Valve Mitigation of Duodenogastric Reflux, Remnant Gastritis and Dumping Syndrome Following Billroth I Reconstruction

BACKGROUND

We have reported the short-term results of pylorus reconstruction gastrectomy (PRG) that prevents duodenogastric reflux (DGR) and remnant gastritis after distal gastrectomy. We herein report the long-term results of the PRG.

PATIENTS AND METHODS

PRG was performed in 37 patients (age 31 to 86 [mean 67.8 ± 12.3] years, male:female = 22:15) with gastric cancer from June 2006 through December 2013. We examined the long-term outcome in 28 patients (age 41 to 86 [mean 67.0 ± 10.7] years, male:female = 18:10) that passed over 3 years after surgery (LTR 44.1 ± 11.7 months), and compared with their short-term result after the operation (STR 13.1 ± 6.9 months). The adverse events of gastric surgery evaluated in this study consisted of the degree of remnant gastritis, the presence of dumping syndrome, and degree of weight loss (%).

RESULTS

There was no difference in the degree of DGR and remnant gastritis by gastroscopic finding between LTR and STR after PRG (P = 0.21). Statistically, there was no difference in the bile acid concentration of remnant gastric juice between LTR and STR (108.4 ± 254.1 vs. 94.0 ± 208.6 μmol/L, P = 0.33), and weight loss of LTR was the same as that of STR (5.67 ± 7.08 vs. 4.59 ± 5.63%, P = 0.34). There were few morphological changes in the reconstructed pylorus by the long-term course, but 2 patients showed mild atrophy.

CONCLUSION

The form of reconstructed pylorus and the effect that reduces side effects of Billroth I seem to last for a long time.

Significance of ultrasonic measurement of pyloric canal diameter in diagnosis of duodenogastric reflux

AIM: To investigate the significance of ultrasonic measurement of pyloric tube diameter in the diagnosis of duodenogastric reflux (DGR).

METHODS: Sixty-eight patients diagnosed with duodenogastric reflux by contrast-enhanced ultrasound at our hospital were selected and divided into a high reflux group and a low reflux group on the basis of reflux time and frequency. Thirty subjects without DGR were used controls. All patients were subjected to measurement of pyloric tube diameter to analyze the relationship between pyloric tube diameter and reflux time and frequency. The ROC curve analysis was also performed.

RESULTS: The pyloric tube diameter in both the high reflux and low reflux groups was significantly higher than that in the control group. The pyloric tube diameter was positively correlated with reflux time and frequency (r = 0.822, 0.718). ROC curve analysis revealed that the area under the curve (AUC) of duodenogastric reflux and high reflux was 0.920 and 0.789, respectively.

CONCLUSION: Ultrasonic measurement of pyloric canal diameter is useful for the clinical diagnosis of DGR.

Comparative evaluation of intragastric bile acids and hepatobiliary scintigraphy in the diagnosis of duodenogastric reflux

AIM: To assess the diagnostic value of a combination of intragastric bile acids and hepatobiliary scintigraphy in the detection of duodenogastric reflux (DGR).

METHODS: The study contained 99 patients with DGR and 70 healthy volunteers who made up the control group. The diagnosis was based on the combination of several objective arguments: a long history of gastric symptoms (i.e., nausea, epigastric pain, and/or bilious vomiting) poorly responsive to medical treatment, gastroesophageal reflux symptoms unresponsive to proton-pump inhibitors, gastritis on upper gastrointestinal (GI) endoscopy and/or at histology, presence of a bilious gastric lake at > 1 upper GI endoscopy, pathologic 24-h intragastric bile monitoring with the Bilitec device. Gastric juice was aspirated in the GI endoscopy and total bile acid (TBA), total bilirubin (TBIL) and direct bilirubin (DBIL) were tested in the clinical laboratory. Continuous data of gastric juice were compared between each group using the independent-samples Mann-Whitney U-test and their relationship was analysed by Spearman’s rank correlation test and Fisher’s linear discriminant analysis. Histopathology of DGR patients and 23 patients with chronic atrophic gastritis was compared by clinical pathologists. Using the Independent-samples Mann-Whitney U-test, DGR index (DGRi) was calculated in 28 patients of DGR group and 19 persons of control group who were subjected to hepatobiliary scintigraphy. Receiver operating characteristic curve was made to determine the sensitivity and specificity of these two methods in the diagnosis of DGR.

RESULTS: The group of patients with DGR showed a statistically higher prevalence of epigastric pain in comparison with control group. There was no significant difference between the histology of gastric mucosa with atrophic gastritis and duodenogastric reflux. The bile acid levels of DGR patients were significantly higher than the control values (Z: TBA: -8.916, DBIL: -3.914, TBIL: -6.197, all P < 0.001). Two of three in the DGR group have a significantly associated with each other (r: TBA/DBIL: 0.362, TBA/TBIL: 0.470, DBIL/TBIL: 0.737, all P < 0.001). The Fisher’s discriminant function is followed: Con: Y = 0.002TBA + 0.048DBIL + 0.032TBIL - 0.986; Reflux: Y = 0.012TBA + 0.076DBIL + 0.089TBIL - 2.614. Eighty-four point zero five percent of original grouped cases were correctly classified by this method. With respect to the DGR group, DGRi were higher than those in the control group with statistically significant differences (Z = -5.224, P < 0.001). Twenty eight patients (59.6%) were deemed to be duodenogastric reflux positive by endoscopy, as compared to 37 patients (78.7%) by hepatobiliary scintigraphy.

CONCLUSION: The integrated use of intragastric bile acid examination and scintigraphy can greatly improve the sensitivity and specificity of the diagnosis of DGR.

Expression of motilin and vasoactive intestinal peptide in gastric mucosa of patients with primary bile reflux gastritis

AIM: To investigate the expression of motilin and vasoactive intestinal peptide (VIP) in gastric mucosa of patients with primary bile reflux gastritis.

METHODS: Seventy-four patients with primary bile reflux gastric were divided into low reflux group (n = 42) and high reflux group (n = 32). A control group was composed of 28 subjects who showed no abnormalities during 24-hour gastric bilirubin monitoring with Bilitec 2000 and gastroscopic examination. The expression of motilin and VIP in biopsy specimens was detected by immunohistochemistry and analyzed using pathology image analysis software.

RESULTS: The expression levels of motilin in the high and low reflux groups were lower than that in the control group (558.93 ± 223.63 and 787.09 ± 252.97 vs 941.50 ± 275.87, respectively; both P < 0.05), while the expression levels of VIP in the high and low reflux groups were higher than in the control group (1700.06 ± 486.55 and 1241.19 ± 359.34 vs 959.00 ± 335.78, respectively; both P < 0.01). The detection rates of metaplasia atrophy in the high and low reflux groups were higher than that in the control group (50.0% and 26.2% vs 7.1%, respectively; P < 0.01 and 0.05). Patients with metaplastic atrophic gastritis had higher reflux rate than those with superficial gastritis (59.3% vs 30.5%, P < 0.05). The detection rate of Helicobacter pylori (H. pylori) decreased with the aggravation of bile reflux (64.3% and 47.6% vs 25.0%, respectively; P < 0.01 and 0.05).

CONCLUSION: The parasecretion of motilin and VIP may play a role in the development of bile reflux gastritis. Bile reflux is one of the risk factors for gastric mucosa injury. Bile reflux can inhibit the infection of H. pylori.

Prevalence of bile reflux in gastroesophageal reflux disease patients not responsive to proton pump inhibitors

AIM: To determine the prevalence and characteristics of bile reflux in gastroesophageal reflux disease (GERD) patients with persistent symptoms who are non-responsive to medical therapy.

METHODS: Sixty-five patients (40 male, 25 female; mean age, 50 ± 7.8 years) who continued to report symptoms after 8 wk of high-dose proton pump inhibitor (PPI) therapy, as well as 18 patients with Barrett’s esophagus, were studied. All patients filled out symptom questionnaires and underwent endoscopy, manometry and combined pH-metry and bilimetry.

RESULTS: There were 4 groups of patients: 22 (26.5%) without esophagitis, 24 (28.9%) grade A-B esophagitis, 19 (22.8%) grade C-D and 18 (21.6%) Barrett’s esophagus. Heartburn was present in 71 patients (85.5%) and regurgitation in 55 (66.2%), with 44 (53%) reporting simultaneous heartburn and regurgitation. The prevalence of pathologic acid reflux in the groups without esophagitis and with grades A-B and C-D esophagitis was 45.4%, 66.6% and 73.6%, respectively. The prevalence of pathologic bilirubin exposure in these 3 groups was 53.3%, 75% and 78.9%, respectively. The overall prevalence of bile reflux in non-responsive patients was 68.7%. Pathologic acid and bile reflux was observed in 22.7% and 58.1% of non-esophagitic patients and esophagitic patients, respectively.

CONCLUSION: The high percentage of patients poorly responsive to PPI therapy may result from poor control of duodenogastroesophageal reflux. Many patients without esophagitis have simultaneous acid and bile reflux, which increases with increasing esophagitis grade.

Physiological duodenogastric reflux in young healthy adults

AIM: To investigate the characteristics of physiological duodenogastric reflux (DGR) in young healthy adults, and to study the relationship between DGR and pathologically altered gastric mucosa.

METHODS: Twenty healthy young volunteers received the conventional endoscopy, 24 h dynamic stomach pH and bile reflux monitoring, HE staining routine pathological examination as well as improved chromatin Giemsa line inspection for H. pylori.

RESULTS: Of 20 cases, two subjects had bile reflux, 6 had H. pylori positive tests and the rest showed normal gastric mucosa or mild antral gastritis. No ulceration, erosions, atrophy or intestinal metaplasia were observed in all subjects (including 6 Helicobacter pylori infection) on endoscopic and histological findings. All subjects were found to have bile reflux at variable degrees (gastric bilirubin absorbance >0.14) and total period of bile reflux (abs>0.14) was 12.5% ± 8.8%. Of all bile reflux events, short reflux events (< 5 min) were 62.8 ± 36.0 times, long reflux events(> 5 min) were 5.9 ± 3.8 times, and the longest reflux duration was 53.5.0 ± 50.3 min, reflux time was significantly longer during upright phase than during supine phase (P = 0.017). But the percentages of pH > 4 times (13.91% ± 10.1%) in stomach were not related to the percentages of bile reflux time.

CONCLUSION: Physiological duodenogastric reflux occurs in young healthy adults. Degree or state of gastric bile reflux is individually different. However, the bile reflux doesn't induce gastric mucosal lesions nor affect gastric pH value.