). Chronic inflammation may lead to atrophy.Metaplasia of the remaining corpus mucosa is common. The degree of gastritis is usually greatest at the lines of anastomosis.
Several mechanisms are responsible:
Bile reflux, which is common after such surgery, damages the gastric mucosa.
Loss of antral gastrin decreases stimulation of parietal and peptic cells, causing atrophy.
Vagotomy may result in a loss of vagal trophic action.
There are no specific symptoms of gastritis. Postgastrectomy gastritis often progresses to severe atrophy and achlorhydria. Production of intrinsic factor may cease with resultant vitamin B12 deficiency Vitamin B12 Deficiency Dietary vitamin B12 deficiency usually results from inadequate absorption, but deficiency can develop in vegans who do not take vitamin supplements. Deficiency causes megaloblastic anemia, damage... read more (which may be worsened by bacterial overgrowth in the afferent loop). The relative risk of gastric adenocarcinoma Stomach Cancer Etiology of stomach cancer is multifactorial, but Helicobacter pylori plays a significant role. Symptoms include early satiety, obstruction, and bleeding but tend to occur late in the... read more 
seems to increase 15 to 20 years after partial gastrectomy; however, given the low absolute incidence of postgastrectomy cancer, routine endoscopic surveillance is probably not cost effective, but upper gastrointestinal symptoms or anemia in such patients should prompt endoscopy.
