acinar cell carcinoma ( acc ) of the pancreas is a rare tumor that is estimated to account for 12% of all pancreatic exocrine tumors [ 1 , 2 ] . because of the lack of clinical experience with acc , its pathophysiology is not well understood . according to previous reports , acc generally shows expansive growth without invasion into the plexus , portal vein , bile duct and pancreatic duct [ 3 , 4 ] . to our knowledge , no previous reports have described hepatic metastasis from acc primarily in the form of a tumor thrombus . we encountered a very rare case of hepatic metastasis with an unusual clinical presentation : a bile duct tumor thrombus ( bdtt ) from pancreatic acc . a 66-year - old woman had undergone total pancreatectomy due to pancreatic acc ( t3n0m0 , stage iia ) 7 years prior to clinical presentation . computed tomography ( ct ) imaging showed a tumorous lesion measuring 7 cm in length and 1 cm in diameter and extending along the intrahepatic bile duct ( b6 ) . during ct imaging , the lesion showed mild enhancement in the early phase and modest washout in the late phase ( fig . ct arteriography ( cta ) showed early enhancement , which corresponded to the tumorous lesion detected by ct(fig . f - fluorodeoxyglucose positron emission tomography / ct ( fdg - pet / ct ) showed high fdg uptake within the corresponding area ( fig . the tumor was primarily confined to the intrahepatic bile duct ( b6 ) without definitive mass formation in the hepatic parenchyma . tumor markers , including cea , ca19 - 9 and dupan - ii , were all within normal limits . since pathological evaluation of the fine needle biopsy specimen from the bdtt revealed histological features that were compatible with those of the patient 's acc resected 7 years before , the lesion was diagnosed as a hepatic metastasis primarily in the form of a bdtt originating from the prior acc . we initiated chemoradiation therapy ( crt ) , consisting of a total radiation dose of 50 gy and the intravenous administration of gemcitabine ( 1,000 mg / m ) concurrently on days 1 , 8 , and 15 during each 4-week cycle . although a modest effect was observed 13 weeks after the initiation of crt , with a decrease in blood flow and size of the bdtt ( fig . 2a ) , the lesion showed an increase in size 19 weeks after the initiation of crt ( fig . thus , surgical resection , including subsegmentectomy ( s6 ) of the liver and complete removal of the bdtt , was performed . pathological evaluation of the resected specimen confirmed a hepatic metastasis primarily consisting of a bdtt that originated from an acc of the pancreas ( intraductal polypoid growth variant ) . the detailed pathological evaluation of the bdtt and the comparison of this tumor 's characteristics with those of the primary pancreatic lesion that was resected 7 years before are presented in a separate report . although our experience is only anecdotal , the case reported here provides several novel observations in regard to the clinical features associated with pancreatic acc . first , it underscores the need for a long - term follow - up for pancreatic acc cases , even after curative resection . this case involved a liver metastasis that was detected more than 5 years postoperatively , which is unique as hepatic metastases normally occur within a relatively short period following resection of the primary lesion [ 7 , 8 ] . second , aggressive surgical resection combined with crt for hepatic metastasis from pancreatic acc should be considered as a treatment option in selected cases . however , the treatment strategy for metastatic or recurrent acc remains controversial even though various treatment options , including chemotherapy , crt and surgical resection , have been reported [ 7 , 8 , 10 , 11 , 12 ] . reported a case of hepatic metastasis from acc that was successfully treated with an aggressive surgical approach . the advantage of crt prior to surgical resection for hepatic metastasis from acc is unclear . however , a preoperative crt strategy might be beneficial especially in marginally resectable cases because a partial response to crt was observed in the case presented here . third , although multimodal approaches may be useful for selected acc cases [ 10 , 11 , 12 ] , careful repeated re - evaluations during the preoperative treatment period are necessary to improve the chances for a curative resection as demonstrated by our current case , in whom the bdtt showed regrowth after a partial response to crt . further studies with a larger number of patients are required to fully understand the pathophysiology of acc and to evaluate the benefits of multimodal treatment strategies for recurrent acc .