Gastric adenocarcinoma is one of the most common malignancies worldwide.Histochemical and immunohistologic analyses classify the phenotypes of gastric adenocarcinoma into several groups based on the variable clinical ...Gastric adenocarcinoma is one of the most common malignancies worldwide.Histochemical and immunohistologic analyses classify the phenotypes of gastric adenocarcinoma into several groups based on the variable clinical and pathologic features.A new and rare variant of gastric adenocarcinoma with chief cell differentiation(GA-CCD)has recently been recognized.Studies reporting the distinct clinicopathologic characteristics proposed the term oxyntic gland polyp/adenoma because of the benign nature of the GACCD.Typically,GA-CCD is a solitary mucosal lesion that develops either in the gastric cardia or fundus.Histologically,this lesion is characterized by tightly clustered glands and anastomosing cords of chief cells.Immunohistochemically,GA-CCD is diffusely positive for mucin(MUC)6 and negative for MUC2and MUC5AC.However,other gastric tumors such as a gastric neuroendocrine tumor or fundic gland polyp have been difficult to exclude.Because GA-CCD tends to be endoscopically misdiagnosed as a neuroendocrine tumor or fundic gland polyp,comprehensive assessment and observation by an endoscopist are strongly recommended.Herein,we report a rare case of oxyntic gland adenoma endoscopically mimicking a gastric neuroendocrine tumor that was successfully removed by endoscopic mucosal resection.展开更多
The fact that the acidsecreting parietal cells undergo continuous renewal has been ignored by many gastroenterologists and cell biologists. In the past, it was thought that these cells were static. However, by using 3...The fact that the acidsecreting parietal cells undergo continuous renewal has been ignored by many gastroenterologists and cell biologists. In the past, it was thought that these cells were static. However, by using 3Hthymidine radioautography in combination with electron microscopy, it was possible to demonstrate that parietal cells belong to a continuously renewing epithelial cell lineage. In the gastric glands, stem cells anchored in the isthmus region are responsible for the production of parietal cells. The stem cells give rise to three main progenitors: prepit, preneck and preparietal cells. Parietal cells develop either directly from the noncycling preparietal cells or less commonly via differentiation of the cycling prepit and preneck cell progenitors. The formation of a parietal cell is a sequential process which involves diminishment of glycocalyx, production of cytoplasmic tubulovesicles, an increase in number and length of microvilli, an increase in number and size of mitochondria, and fi nally, expansion and invagination of the apical membrane with the formation of an intracellular canalicular system. Little is known about the genetic counterparts of these morphological events. However, the time dimension of parietal cell production and the consequences of its alteration on the biological features of the gastric gland are well documented. The production of a new parietal cell takes about 2 d. However, mature parietal cells have a long lifespan during which they migrate bidirectionally while their functional activity for acid secretion gradually diminishes. Following an average lifespan of about 54 d, in mice, old parietal cells undergo degeneration and elimination. Various approaches for genetic alteration of the development of parietal cells have provided evidence in support of their role as governors of the stem/progenitor cell proliferation and differentiation programs. Revealing the dynamic features and the various roles of parietal cells would help in a better understanding of the biological features of the gastric glands and would hopefully help in providing a basis for the development of new strategies for prevention, early detection and/or therapy of various gastric disorders in which parietal cells are involved, such as atrophic gastritis, peptic ulcer disease and gastric cancer.展开更多
文摘Gastric adenocarcinoma is one of the most common malignancies worldwide.Histochemical and immunohistologic analyses classify the phenotypes of gastric adenocarcinoma into several groups based on the variable clinical and pathologic features.A new and rare variant of gastric adenocarcinoma with chief cell differentiation(GA-CCD)has recently been recognized.Studies reporting the distinct clinicopathologic characteristics proposed the term oxyntic gland polyp/adenoma because of the benign nature of the GACCD.Typically,GA-CCD is a solitary mucosal lesion that develops either in the gastric cardia or fundus.Histologically,this lesion is characterized by tightly clustered glands and anastomosing cords of chief cells.Immunohistochemically,GA-CCD is diffusely positive for mucin(MUC)6 and negative for MUC2and MUC5AC.However,other gastric tumors such as a gastric neuroendocrine tumor or fundic gland polyp have been difficult to exclude.Because GA-CCD tends to be endoscopically misdiagnosed as a neuroendocrine tumor or fundic gland polyp,comprehensive assessment and observation by an endoscopist are strongly recommended.Herein,we report a rare case of oxyntic gland adenoma endoscopically mimicking a gastric neuroendocrine tumor that was successfully removed by endoscopic mucosal resection.
基金Supported by Terry Fox Fund for Cancer Research and UAE University
文摘The fact that the acidsecreting parietal cells undergo continuous renewal has been ignored by many gastroenterologists and cell biologists. In the past, it was thought that these cells were static. However, by using 3Hthymidine radioautography in combination with electron microscopy, it was possible to demonstrate that parietal cells belong to a continuously renewing epithelial cell lineage. In the gastric glands, stem cells anchored in the isthmus region are responsible for the production of parietal cells. The stem cells give rise to three main progenitors: prepit, preneck and preparietal cells. Parietal cells develop either directly from the noncycling preparietal cells or less commonly via differentiation of the cycling prepit and preneck cell progenitors. The formation of a parietal cell is a sequential process which involves diminishment of glycocalyx, production of cytoplasmic tubulovesicles, an increase in number and length of microvilli, an increase in number and size of mitochondria, and fi nally, expansion and invagination of the apical membrane with the formation of an intracellular canalicular system. Little is known about the genetic counterparts of these morphological events. However, the time dimension of parietal cell production and the consequences of its alteration on the biological features of the gastric gland are well documented. The production of a new parietal cell takes about 2 d. However, mature parietal cells have a long lifespan during which they migrate bidirectionally while their functional activity for acid secretion gradually diminishes. Following an average lifespan of about 54 d, in mice, old parietal cells undergo degeneration and elimination. Various approaches for genetic alteration of the development of parietal cells have provided evidence in support of their role as governors of the stem/progenitor cell proliferation and differentiation programs. Revealing the dynamic features and the various roles of parietal cells would help in a better understanding of the biological features of the gastric glands and would hopefully help in providing a basis for the development of new strategies for prevention, early detection and/or therapy of various gastric disorders in which parietal cells are involved, such as atrophic gastritis, peptic ulcer disease and gastric cancer.
