gastrointestinal stromal tumors ( gists ) , which arise primarily in the gut wall , are most commonly mesenchymal neoplasms closely related to the interstitial cells of cajal .
gists typically carry gain - of - function mutations in genes encoding the kit receptor tyrosine kinase ( cd117 ) or platelet - derived growth factor receptor a , both of which are involved in cell survival , development and proliferation .
although gists can arise at any location in the gastrointestinal tract , they are found most often in the stomach ( 60 - 70% ) , followed by the small intestine ( 20 - 30% ) , colon and rectum ( 5% ) , and esophagus ( < 5% ) . in most cases in the stomach ,
gists show the appearance of a submucosal tumor , with a broad base and smooth surface within normal gastric mucosa , and sometimes have central 
delle or depression . in larger cases , central ulceration or necrosis presenting with gastrointestinal bleeding
the gist of the stomach described in this report was a rare case , with narrow stalk - like based , uneven protruding mass presenting with severe acute anemia despite small size .
a 56-year - old woman was admitted to fujita health university with epigastric pain and nausea during the previous one month .
laboratory evaluation on admission showed severe anemia ( red blood cell count 138  10/l , hemoglobin level 4.3 g / dl , hematocrit 13.7% ) ( table 1 ) .
esophagogastroduodenoscopy revealed a narrow stalk - like based , hemorrhagic and uneven protruding lesion in the lesser curvature of the gastric upper corpus ( fig .
1 ) . endoscopic ultrasonography showed a low echoic mass , measuring 2.0 cm in diameter , within the fourth layer , suggesting that the tumor originated from the intrinsic muscle layer , and showed growth to the mucosal side ( fig .
the labeling index ( li ) for mib-1 , determined by counting positively stained nuclei among 1,000 tumor cells , was 1% .
although the histological findings suggested that the tumor was probably a benign gist , laparoscopy - assisted local resection was performed after 2 weeks because the patient had continuous severe anemia and epigastric pain .
the resected tumor was 1.8  1.5  1.0 cm in size within the locally resected surgical speciemen .
the tumor was elastic but hard in consistently , and its surface was uneven and irregular ( fig .
the tumor cells originated from the intrinsic muscle layer and showed growth to the mucosal side , cropping out to the surface in most areas of the protruding lesion .
histological assessment revealed that the tumor was composed of elongated spindle - like cells , containing rounded or oval , relatively uniform nuclei without apparent atypia ( fig .
the li for mib-1 , determined by counting positively stained nuclei among 1,000 tumor cells , was about 1% ( fig .
immunohistochemical staining of the tumor by the avidin - biotin peroxidase complex method showed that most of the tumor cells demonstrated immunoreactivity for kit ( fig .
the tumor described in this report showed immunoreactivity for kit and cd34 , but not for asma , s100 and desmin , implying that the tumor was pathologically a gist   with a lack of differentiation toward smooth muscle , and neural elements .
most gists in the stomach generally show the appearance of submucosal tumors , with a broad base and smooth surface within normal gastric mucosa , and sometimes have small central 
delle or depression . in larger cases , central ulceration or necrosis presenting with gastrointestinal bleeding
however , the gist of the stomach described in this report showed narrow stalk - like based , uneven protruding mass presenting with severe acute anemia despite the small size of less than 2 cm , and local resection was needed due to continuous severe anemia and epigastric pain .
although the association between the patient 's gastric symptoms and this small submucosal tumor is not fully understood , the considerable amount of blood in the stomach due to continuous bleeding may have led to the gastric symptoms such as epigastric pain and nausea .
histological assessment showed that the tumor cells showed growth to the mucosal side , cropping out to the surface in most areas of the protruding lesion , and only a small part of the tumor was within nontumoral gastric mucosa , despite the tumor cells originating from the intrinsic muscle layer .
thus the case of our report may be a rare case for its morphological appearance as well as clinical course .
metastasis and/or recurrence after surgery may be observed for several gists , despite an initial diagnosis of a benign tumor .
therefore , it is recommended to apply risk classification based on tumor size and mitoic count under a hpf .
the mib-1(ki-67 ) li or the presence or absence of tumor necrosis is also reported to reflect proliferation activities and malignant outcome .
the gist described in our report was less than 2 cm in diameter without necrosis , and had low mitotic activity ( 0/50 hpf ) and li for mib-1 ( about 1% ) . in this context
, our gist may have a very low malignant potential and thus metastasis and/or recurrence may not be observed in the future .
actually , the patient in this report has been disease - free 18 months after surgery .
 we report the case of a 56-year - old woman who had a gastrointestinal stromal tumor ( gist ) of the stomach . 
 she was admitted to our hospital for epigastric pain , nausea , and severe acute anemia ( hemoglobin level 4.3 g / dl ) . 
 esophagogastroduodenoscopy revealed a narrow stalk - like based , hemorrhagic and uneven protruding lesion in the lesser curvature of the gastric upper corpus . 
 although the tumor was less than 2 cm in diameter and was probably a benign gist according to histology , laparoscopy - assisted local resection was needed because the patient had continuous severe anemia and epigastric pain . 
 histological assessment showed that the elongated spindle - like tumor cells originated from the intrinsic muscle layer , and was shown with growth to the mucosal side , cropping out to the surface in most areas of the protruding lesion . 
 only a small part of the tumor was within nontumoral gastric mucosa . 
 most of the tumor cells demonstrated immunoreactivity for kit and cd34 in the cytoplasm but not for sma , s100 , and desmin . 
 mitotic activity ( 0/50 high power field ) and the labeling index for mib-1 ( about 1% ) were low . 
 the gist of the stomach described in this report was a rare case with a narrow stalk - like based , uneven protruding mass presenting with severe acute anemia despite small size . 
Introduction
Case Report
Discussion