Plexiform angiomyxoid myofibroblastic tumor of the stomach is a unique mesenchymal tumor that we first described in 2007.The tumor is very rare,and to date,only 18 cases confirmed by immunohistochemistry have been rep...Plexiform angiomyxoid myofibroblastic tumor of the stomach is a unique mesenchymal tumor that we first described in 2007.The tumor is very rare,and to date,only 18 cases confirmed by immunohistochemistry have been reported in the literature.The patients' ages ranged from 7 to 75 years(mean,43 years),and the male-to-female ratio was approximately 1:1.Representative clinical symptoms are ulceration,associated upper gastrointestinal bleeding(hematemesis),and anemia.The tumors are located at the antrum in all cases,and grossly,the tumor is whitish to brownish or reddish,and forms a lobulated submucosal or transmural mass.Microscopically,the tumor is characterized by a plexiform growth pattern,the proliferation of cytologically bland spindle cells,and a myxoid stroma that is rich in small vessels and positive for Alcian blue stain.Immunohistochemically,the tumor cells are positive for α-smooth muscle actin and negative for KIT and CD34.Differential diagnoses include gastrointestinal stromal tumor and other mesenchymal tumors of the gastrointestinal tract.Some authors proposed that this tumor should be designated as "plexiform fibromyxoma",but this designation might cause confusion.The tumor is probably benign and thus far,neither recurrence nor metastasis has been reported.展开更多
Angiogenesis is a dynamic,hypoxia-stimulated and growth factor-dependent process,and is currently referred to as the formation of new vessels from preexisting blood vessels.Experimental and clinical studies have unequ...Angiogenesis is a dynamic,hypoxia-stimulated and growth factor-dependent process,and is currently referred to as the formation of new vessels from preexisting blood vessels.Experimental and clinical studies have unequivocally reported that hepatic angiogenesis,irrespective of aetiology,occurs in conditions of chronic liver diseases(CLDs) characterized by perpetuation of cell injury and death,inflammatory response and progressive fibrogenesis.Angiogenesis and related changes in liver vascular architecture,that in turn concur to increase vascular resistance and portal hypertension and to decrease parenchymal perfusion,have been proposed to favour fibrogenic progression of the disease towards the end-point of cirrhosis.Moreover,hepatic angiogenesis has also been proposed to modulate the genesis of portal-systemic shunts and increase splanchnic blood flow,thus potentially affecting complications of cirrhosis.Hepatic angiogenesis is also crucial for the growth and progression of hepatocellular carcinoma.Recent literature has identified a number of cellular and molecular mechanisms governing the cross-talk between angiogenesis and fibrogenesis,with a specifi c emphasis on the crucial role of hypoxic conditions and hepatic stellate cells,particularly when activated to the myofibroblast-like pro-fibrogenic.Experimental anti-angiogenic therapy has been proven to be effective in limiting the progression of CLDs in animal models.From a clinical point of view,anti-angiogenic therapy is currently emerging as a new pharmacologic intervention in patients with advanced fibrosis and cirrhosis.展开更多
文摘Plexiform angiomyxoid myofibroblastic tumor of the stomach is a unique mesenchymal tumor that we first described in 2007.The tumor is very rare,and to date,only 18 cases confirmed by immunohistochemistry have been reported in the literature.The patients' ages ranged from 7 to 75 years(mean,43 years),and the male-to-female ratio was approximately 1:1.Representative clinical symptoms are ulceration,associated upper gastrointestinal bleeding(hematemesis),and anemia.The tumors are located at the antrum in all cases,and grossly,the tumor is whitish to brownish or reddish,and forms a lobulated submucosal or transmural mass.Microscopically,the tumor is characterized by a plexiform growth pattern,the proliferation of cytologically bland spindle cells,and a myxoid stroma that is rich in small vessels and positive for Alcian blue stain.Immunohistochemically,the tumor cells are positive for α-smooth muscle actin and negative for KIT and CD34.Differential diagnoses include gastrointestinal stromal tumor and other mesenchymal tumors of the gastrointestinal tract.Some authors proposed that this tumor should be designated as "plexiform fibromyxoma",but this designation might cause confusion.The tumor is probably benign and thus far,neither recurrence nor metastasis has been reported.
文摘Angiogenesis is a dynamic,hypoxia-stimulated and growth factor-dependent process,and is currently referred to as the formation of new vessels from preexisting blood vessels.Experimental and clinical studies have unequivocally reported that hepatic angiogenesis,irrespective of aetiology,occurs in conditions of chronic liver diseases(CLDs) characterized by perpetuation of cell injury and death,inflammatory response and progressive fibrogenesis.Angiogenesis and related changes in liver vascular architecture,that in turn concur to increase vascular resistance and portal hypertension and to decrease parenchymal perfusion,have been proposed to favour fibrogenic progression of the disease towards the end-point of cirrhosis.Moreover,hepatic angiogenesis has also been proposed to modulate the genesis of portal-systemic shunts and increase splanchnic blood flow,thus potentially affecting complications of cirrhosis.Hepatic angiogenesis is also crucial for the growth and progression of hepatocellular carcinoma.Recent literature has identified a number of cellular and molecular mechanisms governing the cross-talk between angiogenesis and fibrogenesis,with a specifi c emphasis on the crucial role of hypoxic conditions and hepatic stellate cells,particularly when activated to the myofibroblast-like pro-fibrogenic.Experimental anti-angiogenic therapy has been proven to be effective in limiting the progression of CLDs in animal models.From a clinical point of view,anti-angiogenic therapy is currently emerging as a new pharmacologic intervention in patients with advanced fibrosis and cirrhosis.
