approximately 6% of patients undergoing dialysis have malignancies , and the number of these patients undergoing chemotherapy continues to increase . chemotherapy in dialysis patients is challenging because excretion of the drug differs between dialysis and non - dialysis patients . drugs that are excreted by dialysis may show reduced efficacy , while drugs that are not excreted may cause adverse events . imatinib is an effective and safe therapy for kit - positive gastrointestinal stromal tumors ( gist ) [ 2 , 3 , 4 , 5 ] . however , the efficacy and safety of imatinib treatment in dialysis patients remain unclear because clinical trials have not been conducted in this population . we report a patient with duodenal gist undergoing dialysis who was treated with regular - dose imatinib and remained stable with no adverse events for 4 months . we also present a literature review of the efficacy and safety of imatinib treatment in patients with gist undergoing dialysis . in a 75-year - old japanese man , a large duodenal tumor was identified on computed tomography ( ct ) in 2008 and was suspected as gist on endoscopic ultrasonography . however , the patient refused further investigation and underwent a follow - up visit . he also had chronic kidney disease , due to type 2 diabetes , and began a course of hemodialysis three times weekly in 2014 . a large - volume and painless tarry stool with hemorrhagic shock occurred in april 2014 . a complete blood count showed a hemoglobin level of 6.3 g / dl , and the patient required transfusion of 32 units of packed red blood cells to recover a general condition . contrast agent - enhanced ct scans revealed a duodenal tumor 14 cm in diameter , with multiple liver and bone metastases . the patient underwent an urgent upper endoscopy , which showed a 3.5-cm submucosal tumor with stigmata of recent hemorrhage in the bulb of the duodenum . endoscopic hemostasis was not conducted due to the large exposed vessel , and an urgent pancreaticoduodenectomy was performed to achieve hemostasis . the resected tumor showed a gist composed of spindle - shaped cells with positive staining for kit and cd34 and negative staining for s-100 ; the mitotic count was 12 per 50 high - power fields , and the mib-1 labeling index was 10% ( fig . the patient was treated with imatinib at a dose of 400 mg daily ( orally ) . complete blood counts showed a white blood cell count in the range of 3669  10/l , a hemoglobin level range of 8.9 - 10.2 g / dl , and a platelet count range of 162265  10/l . furthermore , no severe adverse event , including liver functional impairment , intestinal pneumonia , or stevens - johnson syndrome occurred . however , mild adverse events including fatigue and edema were observed , and his metastases remained stable for 4 months . finally , imatinib treatment was discontinued because of progression of the disease and worsening performance status in january 2015 . the patient died of duodenal perforation induced by residual tumor progression in february 2015 , 6 years after the initial diagnosis and 5 months after chemotherapy for gist . we administered regular - dose imatinib in a patient with multiple metastases from gist undergoing dialysis . the patient remained stable without any adverse event associated with imatinib for 4 months . to our knowledge , this is the first literature review and third case report of imatinib treatment for gist in patients undergoing dialysis . several cytotoxic drug therapies have been reported in patients with major gastrointestinal tract malignancies undergoing dialysis . dialysis patients with esophageal cancer have been administered 5-fluorouracil and cisplatin [ 7 , 8 , 9 ] and dialysis patients with gastric cancer have been administered tegafur - uracil , docetaxel , and irinotecan [ 10 , 13 ] . dialysis patients with colon cancer have been treated with tegafur - uracil , irinotecan , and oxaliplatin [ 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 ] . in these cases , most cytotoxic drugs were used safely without dose modification , but irinotecan caused severe myelosuppression and resulted in death [ 15 , 18 ] . however , available data on molecular - specific therapies in dialysis patients are limited , and treatment - related issues are unclear . pappas et al .   reported a 44-year - old woman with rectal gist and liver metastasis undergoing dialysis for 1 year . six years later , she was diagnosed with liver metastasis of the resected rectal gist and received regular - dose imatinib for the liver metastasis . no severe adverse events associated with imatinib occurred , and the liver metastasis remained in partial remission for 12 months . reported a 69-year - old japanese man with peritoneal gist undergoing dialysis for 9 years . the main lesion of the peritoneum gist was resected , and he received regular - dose imatinib for residual disease . no severe adverse event occurred , and the residual disease remained in partial remission for 20 months . in our case and the previous cases , no severe adverse events were associated with imatinib . a previous study evaluated the pharmacokinetics of both imatinib and its metabolite cgp74588 in dialysis patients and reported that the pharmacokinetics of dialysis patients were similar to those of non - dialysis patients . the clinical importance of these data was supported by our results , and we also consider that dialysis patients can be treated safely with imatinib . heart failure was not observed in our case due to strict water management , but physicians should pay careful attention to patients with these findings . previous studies reported good clinical outcomes , with no recurrence after 1220 months [ 25 , 26 ] . imatinib treatment without dose reduction may contribute to good responses in patients undergoing dialysis as well as those without dialysis . in our case , overall survival was shorter than that in previous reports [ 25 , 26 ] , but the difference may be due to the clinical stage at the time of initiation of imatinib treatment . our case had poor prognostic factors , such as a lesion size larger than 11.1 cm , wall invasion , and hepatic metastasis . in conclusion , regular - dose imatinib was an effective and safe treatment in a patient with gist undergoing dialysis .
the number of cancer patients undergoing dialysis has been increasing , and the number of these patients on chemotherapy is also increasing . 
 imatinib is an effective and safe therapy for kit - positive gastrointestinal stromal tumors ( gist ) , but the efficacy and safety of imatinib in dialysis patients remain unclear . because clinical trials have not been conducted in this population , more investigations are required . 
 we report on a 75-year - old japanese man undergoing dialysis who presented with massive tarry stool from a duodenal gist . 
 the duodenal gist was 14 cm in diameter with multiple liver and bone metastases . 
 the patient underwent an urgent pancreaticoduodenectomy to achieve hemostasis . 
 after surgery , he was administered imatinib 400 mg / day . 
 no severe adverse event including myelosuppression , congestive heart failure , liver functional impairment , intestinal pneumonia , or steven - johnson syndrome occurred , and the liver metastasis remained stable for 4 months . during chemotherapy , 
 hemodialysis continued three times per week without adverse events . 
 we suggest that regular - dose imatinib is an effective and safe treatment in patients with gist undergoing dialysis . 
 in addition , we present a literature review of the effectiveness and safety of imatinib treatment in dialysis patients .