gastrointestinal stromal tumors ( gists ) are thought to arise from the interstitial cells of cajal ( icc ) , which function as gastrointestinal pacemaker cells . gists exhibit a wide clinical spectrum , from benign to frankly malignant , and more than 30% of the patients with malignant tumors develop local recurrence and distant metastases who undergo resection with curative intent . the most common metastatic site is the liver ( 65% ) . to the best of our knowledge , rare reports of metastasis to the spleen exist . here , we document a case of recurring gist of the stomach that metastasized to the spleen . a 59-year - old man visited our hospital for an examination of a palpable mass in the left abdomen . fourteen months prior to his visit , the patient underwent gastric wedge resection to remove a gist of the gastric cardia ( fig . 1 ) . at the time of surgery , no evidence of metastatic disease was observed and the pathological interpretation was a high - risk gist . a follow - up computed tomography ( ct ) scan of the abdomen revealed a partially necrotic solid mass ( 9.8  7.6 cm ) and enhancing mass in the spleen ( 2.3 cm ) ( fig . 2 ) . two masses ( 8.3  5.5 cm , 10.7  8.5 cm ) were also found in the liver . laparoscopic examination indicated peritoneal seeding , and palliative surgery ( completion gastrectomy , splenectomy , omentectomy , and left hepatectomy ) was performed . upon macroscopic examination , a 0.8-cm tumor was found in the stomach of the cardia , 2.3 cm distal to the proximal margin , and two partially necrotic masses were detected in the liver and spleen ( 13.5  10.7 cm and 12.2  11 cm , respectively ) ( fig . a histopathological examination revealed that the stomach tumor was composed of spindle - shaped cells with numerous mitoses ( > 10 mitoses per 50 hpf ) ( fig . 4 ) . almost all cells showed immunoreactivity for c - kit and cd34 , but not for -smooth muscle actin , s-100 , or desmin . the histology of the masse in the spleen was similar to that of the gastric lesion . after surgery , he received chemotherapy with imatinib mesylate ( a single daily oral dose of imatinib 400 mg ) and showed a high response . icc , the intestinal pacemaker cells , may share the same nonneoplastic progenitor cells as gists ; these tissues show ultrastructural similarities in terms of smooth muscle and neural differentiation . most gists ( 50 to 72% ) show positive staining for cd34 , but immunohistochemical staining for kit ( cd117 ) is a more specific diagnostic criterion . about 5% of gists are so - called wildtype gists but still express the kit receptor . these cd117-negative tumors often show other mutations in platelet - derived growth factor receptor - a , another tyrosine kinase . gists may occur anywhere along the length of the digestive tract , from the esophagus to the anus . approximately 60 to 70% of gists arise in the stomach , 20 to 30% in the small intestine , 5% in the colon and rectum . early - stage gists often do not present any symptoms . because most gists show an exophytic growth pattern and arise within the muscularis propria of the stomach or intestinal wall , they present as dominant masses outside of the organ of origin . true gists can be identified from other tumors by histological analysis and the expression of kit ( cd117 ) and cd34 . although gists are generally fragile and soft , creating a high possibility of bleeding , rupture , and tumor dissemination , preoperative histological confirmation is generally warranted for potentially resectable tumors whenever possible without major complications . among the various parameters used to predict clinical behavior , mitotic index and tumor size are considered to be the most reliable prognostic indicators ; tumor size , in particular , shows strong associations with survival and recurrence . according to fletcher et al . , gists can be divided into categories based on size and mitoses : very low risk , low risk , intermediate risk , and high risk . bucher et al .   proposed a revised classification of gists according to malignancy and other parameters discussed in the literature . gists exhibiting fewer than four minor criteria are considered of low malignant potential , whereas gists that show four or five minor criteria or one major criterion are classified as high malignant potential , for which the 5-year survival rate is less than 20% . recurrent disease , however , is a serious problem , and the preferred treatment modality for recurrent tumors is to treat with drug . gist patients also benefit from drug therapy using the specific molecular inhibitor , imatinib mesylate ( gleevec ) . this therapy is beneficial in unresectable diseases , as well as an adjuvant therapy after the resection of primary gist . although complete recovery was not achieved , the patients showed a significant response with imatinib mesylate . in spite of clear surgical margins and no definite capsular tearing during the first operation , capsular tearing and tumor seeding could be the causes of treatment failure during initial operation . so , surgeons should be careful not to occur capsular tearing and tumor seeding to prevent the recurrence . here , we report a case of recurring gist of the stomach that metastasized to the spleen and the liver . to the best of our knowledge ,