the incidence of vesicoenteric fistulas has been reported to occur in 0.01% to 0.05% of surgical admissions1 ) . in one study of 56 instances of vesicoenteric fistulas ,
hepatocellular carcinomas ( hccs ) account for 90% of primary liver cancers ; up to 80% of hccs occur in korea occur in patients with cirrhotic livers . according to our literature review ,
several malignancies have been reported as causes of ileovesical fistula , though such complications have not yet been reported to be caused by hcc . here
, we report a case of ileovesical fistula caused by hcc arising from the noncirrhotic liver .
a 27-year - old man was referred to our hospital for the evaluation of hepatic masses . he had consumed 30.0 g alcohol twice weekly for 8 years . on presentation , his vital signs were stable and the physical examination was normal .
viral marker study showed that hbs antigen was negative , anti - hbs antibody positive , and anti - hcv negative .
-fetoprotein ( fp ) was over 50,000 iu / ml and carcinoembryonic antigen ( cea ) was 4.94 ng / ml . abdominal computed tomography ( ct ) with enhancement revealed two heterogeneous hypodense masses in the right hepatic lobe of about 2.4  2 cm and 3.4  4 cm . no cirrhotic change was observed in the liver .
liver magnetic resonance imaging ( mri ) revealed two relatively well - defined masses in the right hepatic lobe ( figure 1 ) .
these lesions were homogeneous low signal intensity on t1-weighted image and slightly inhomogeneous high signal change on t2-weighted image .
immunohistochemical stains were positive for cytokeratin ( ck ) , epithelial membrane antigen ( ema ) , fp , and hepatocyte - specific antigen ( hsa ) .
however , evidence of cirrhosis and chronic injury were absent . under the diagnosis of hcc ,
two months later , follow - up ct scan showed a newly developed mass in the caudate lobe about 4.5  4.0 cm in size , with several daughter nodules .
follow - up ct scan after 3 weeks showed defective lipiodol uptake masses in both the right hepatic lobe and the caudate lobe with remnant tumoral enhancement .
several days later , the patient complained of dysuria , fecaluria , and intermittent lower abdominal pain . pelvic ct scan showed a lobulated soft tissue mass about 6 cm in size ( figure 3 ) .
barium study of the small bowel showed a fistula between the small bowel loop and the urinary bladder ( figure 4 ) .
there were soft tissue masses between the ileum and the bladder and multiple lymphadenopathies at the mesenteric root .
adhesion and fistula were found between the ileum at 10 cm proximal to the ileocecal valve and the dome of the bladder .
the distal 65 cm of ileum was segmentally resected and anastomosed end - to - end .
several malignancies have been reported to be causes of ileovesical fistula . according to our literature review ,
these include bladder cancer , lymphoid malignancies , and others1 , 3 - 5 ) .
although other various malignancies themselves were not direct causes of ileovesical fistula , radiation enteritis complicated by radiation therapy could also cause the ileovesical fistula6 ) .
in korea , about 80% of hccs occur in patients with cirrhotic livers . in our case , hcc occurred in the noncirrhotic liver , and the cause remains uncertain . in one study of 403 patients with hcc , 148 patients ( 37% ) with extrahepatic metastases were identified .
the lung , abdominal lymph nodes , and bone are the most common sites of extrahepatic metastatic hcc .
peritoneal metastases were illustrated at ct scan in 16 ( 11% ) of 148 patients with extrahepatic metastatic hcc7 ) .
ho et al . reported that 3% of patients with hccs in noncirrhotic liver involved the peritoneum8 ) .
fecaluria , abdominal pain , and pneumaturia were the most common presenting symptoms of vesicoenteric fistulas .
other symptoms were dysuria , gross hematuria , fever and chills , diarrhea , and urine per rectum .
the diagnosis of vesicoenteric fistula can be highly indicated by the above mentioned symptoms , using various diagnostic tests to establish diagnosis . in our particular case
, cystoscopic and cystographic examinations showed inflammatory mucosal changes on the dome of the urinary bladder , but could not detect a fistula .
cystoscopy revealed either the fistula itself or highly suggestive , localized mucosal abnormalities ( " herald lesions " ) in 86% .
ct scan revealed abnormalities , such as pelvic masses or bladder or intestinal wall thickening ( 87% ) , and revealed a fistula ( 24% ) . it should be possible to establish the diagnosis of a vesicoenteric fistula through a combination of cystoscopy , cystography , and barium study in almost all patients .
other diagnostic tests for vesicoenteric fistulas include sigmoidoscopy or colonoscopy , intravenous urography , radioisotope studies , and so on .
forms of treatment for vesicoenteric fistula include diverting enterostomy , single stage repair , and multi - staged repair . when secondary to radiation necrosis and recurrent tumor
, fistulas have an extremely poor outlook with some palliation afforded by a diverting colostomy2 ) .
multi - staged repair is limited to those patients with evidence of intestinal obstruction , uncontrolled local sepsis , and questions of intestinal viability9 ) . in summary
, we experienced one case of ileovesical fistula , which was caused by hcc arising from noncirrhotic liver .
the combination of cystoscopy , cystography , and barium study of the small bowel confirmed the diagnosis of ileovesical fistula , and single stage repair was performed successfully .
 ileovesical fistula is a very rare clinical entity , the most frequent cause of which is crohn 's disease . 
 furthermore , it is an exceptionally rare complication of malignancies . 
 we experienced one case of ileovesical fistula which had been caused by hepatocellular carcinoma ( hcc ) arising from the noncirrhotic liver.a 27-year - old man was diagnosed with hcc in a noncirrhotic liver . despite treatment with transarterial chemoembolization ( tace ) , the disease status became more aggravated . 
 the patient complained of dysuria , fecaluria , and intermittent lower abdominal pain . 
 pelvic ct scan showed a soft tissue mass of 6 cm abutting on the distal ileum which was downwardly displaced . 
 barium study of the small bowel showed a fistula between the small bowel loop and the urinary bladder . upon operation , adhesion and 
 fistula were found between the ileum and the urinary bladder . 
 the microscopic findings of the surgical specimen were compatible with metastatic hcc . 
 we confirmed that ileovesical fistula had been caused by metastatic hcc . 
INTRODUCTION
CASE REPORT
DISCUSSION