Controversies of cardiac glands in the proximal stomach: A critical review

Abstract

Cardiac glands (CG), along with oxyntocardiac glands, in a normal human constitute cardiac mucosa (CM) that is positioned in the proximal stomach with a length of 10-30 mm, according to traditional teaching. This doctrine has been recently challenged. On the basis of studies on autopsy and biopsy materials in the esophagogastric junction region, some investigators have reported the presence of CG in only 50% of the general US population. They believed that CG were an acquired, metaplastic lesion as a result of gastroesophageal reflux disease. Subsequent recent study results from other research groups showed the presence of CG in the proximal stomach in embryos, fetuses, pediatric, and adult patients in most Europeans and Americans, and almost all Japanese and Chinese patients. These new data showed the following important findings: (i) CG are confirmed to be congenital in the proximal stomach; (ii) the length of CM is much shorter, approximately 5 mm in Caucasians in Europe and North America, and approximately 13 mm in Japanese and probably also in Chinese; (iii) CG are also present in the distal superficial esophagus underneath squamous mucosa in almost all Japanese and Chinese patients, but not so common in Caucasians in Europe, and not clear in Caucasians in North America. The recent data indicate a clear difference in the distribution of CG in the proximal stomach among different ethnic populations, and might explain different disease pathogenesis mechanisms among various ethnic patient groups.

Recent advances in proximal gastric carcinoma

“…They reported the findings of cardiac glands in all cases, which is confirmed by two pediatric autopsy studies and also by two adult studies . Taken together, the mounting evidence sustains the congenital nature of cardiac mucosa in human beings …”

Emerging evidence supports grouping by location of early gastric carcinoma for appropriate clinical management in Chinese patients

“…Gastric mucosa located in the fundus and corpus consists of identical oxyntic glands with chief cells, parietal cells, and stem cells, which are fundamentally different from the gastric mucous glands in the cardia or in the antrum-pylorus. In a multicenter study carried out in Jiangsu Province, China 24 the prevalence of EGC in the fundus-corpus was 18.8%, which is considerably lower than that in the cardia (23.3%) or in the antrum-pylorus (58.0%) ( Table 2). Importantly, in this Chinese patient population the prevalence of EGC in the fundus was only 0.9% ( 26 In those young Chinese patients with early-onset gastric cancer, H. pylori infection did not appear to be a significant risk factor.…”

“…While the pathogenetic mechanisms of EGC in the cardia remain elusive, the tumor arises in the cardiac mucosa, which is much more intricate than any other mucosa in non‐cardiac locations. It has been well documented in almost all ethnic populations investigated that gastric cardiac mucosa is present at birth and thus it is deemed to be congenital in nature . It is primarily composed of mucous cells, some parietal cells, rare endocrine cells, undifferentiated cells, and importantly, residual embryonic stem cells, which may be responsible for the high heterogeneity of histopathologic patterns of EGC in the cardia .…”

Increased Incidence of Endoscopic Erosive Esophagitis in Solid Organ Transplant Recipients

“…In addition, increased incidence of de novo esophageal cancer in the population of liver transplant recipients has been reported 4,5. Accumulating evidence suggests that gastric acid is the major factor in the pathogenesis of gastroesophageal reflux disease and its complications, including erosive esophagitis (EE), Barrett's esophagus (BE), and esophageal adenocarcinoma 6,7. In the case of BE, which is recognized as a complication of EE and a pre-malignant condition that may lead to the development of esophageal adenocarcinoma, the proximal level of the squamocolumnar junction no longer coincides with the gastroesophageal junction 8,9…”