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a 43-year - old woman positive for hepatitis b surface antigen was diagnosed as having hepatocellular carcinoma ( hcc ) with two intrahepatic tumor nodules , one nodule 2 cm in diameter in the left lateral segment of the liver and the other nodule 3.5 cm in diameter in the dome .
the patient underwent one session of transarterial chemoembolization ( tace ) , followed by percutaneous ethanol injection targeting the area of the residual viable tumor in the liver dome .
however , two months later , a viable portion was found to be present at the margin of the nodule in the hepatic dome and the patient was referred to our center . at that time , the laboratory test results included an aspartate transaminase ( ast ) level of 86
iu / l ) , total bilirubin level of 1.0 mg / dl ( reference , 0.2 - 1.2 mg / dl ) and alpha - fetoprotein level of 1,460 ng / ml ( reference , 0 - 20 ng / ml ) .
rfa was performed percutaneously under ultrasonographic guidance , with the use of local anesthesia and conscious sedation . a single , 17-g , internally cooled electrode ( valleylab , burlington , ma ) was used and radiofrequency current was emitted for 12 minutes with a 200 w generator set to deliver maximum power with the automatic impedance control method .
two ablations were performed with the use of the same method . a follow - up
ct scan obtained immediately after rfa showed complete ablation of the hcc without direct evidence of diaphragmatic injury except for a small amount of reactive pleural effusion ( fig .
the patient reported pain at the right upper quadrant of the abdomen and right shoulder after rfa and the pain gradually improved over five days with the administration of analgesics .
the patient developed a 38.0 fever on the next day after rfa , which subsided after one day .
two months after rfa , the patient revisited our hospital with a complaint of a productive cough with large amounts of green - yellow sputum ( up to 200 ml per day ) , accompanied with a 38.4 fever with chills and right upper quadrant abdominal pain .
decreases in breath sounds on the right lower lung field and slight tenderness to percussion of the right upper quadrant of the abdomen were noted on a physical examination .
plain chest radiograph demonstrated the presence of an ill - defined consolidation in the right lower lobe with right - sided pleural effusion .
an abdominal ct scan showed the presence of a liver abscess at the rfa site and pneumonia , with a small abscess in the right lower lung , suggestive of a focal diaphragmatic defect with communication between the lung and liver abscesses ( fig .
ultrasonography - guided percutaneous drainage of the liver abscess with a 10.2 fr pigtail catheter was performed and 10 ml of thick dark - yellowish pus mixed with necrotic debris was drained .
contrast material injection via the needle demonstrated the presence of opacified cavities of the lung and the bronchial tree communicating with the biliary tree , which was consistent with a bbf ( fig .
no organism other than bacillus spp , which is a common contaminant , was isolated from a culture of the drainage material .
following catheter insertion and treatment with antibiotics , symptoms including fever and bilioptysis were markedly improved .
bile mixed with pus ( 20 to 100 ml daily ) was drained initially , but the rate of drainage gradually decreased to less than 10 ml per day over a month .
follow - up abdominal ct scans obtained five weeks after catheter insertion showed the presence of a small residual lesion with low attenuation in the hepatic dome around the catheter , and repeated cholangiography confirmed no leakage of contrast material through the fistula .
however , fever and productive cough with sputum containing bile resumed the day after removal of the pigtail catheter .
a new cavitary lesion with low attenuation and parenchymal consolidation in the right basal lung were observed on ct images , suggesting reopening of the bbf .
a pigtail catheter was reinserted into the remnant abscess in the liver through the previous drainage tract .
percutaneous tubography showed filling of the contrast material in the right lower lobe of the lung , with contrast material leakage into the right subphrenic space , indicating the presence of a bbf although there was no definite communication between the biliary and bronchial systems ( fig .
thereafter , the amount of percutaneous drainage decreased gradually and the lesions in the liver and lung shrank significantly , as shown on follow - up ct scans three weeks after reinsertion of the pigtail catheter ( fig .
as there was no drainage for a week and the patient did not complain of any fistula - related symptoms , the pigtail catheter was removed .
four weeks after removal , there was no evidence of a bbf or other related lesions on ct images .
two months later , the patient underwent a repeat session of rfa for a recurrent hcc in segment 7 without any treatment - related complications , including a bbf .
radiofrequency ablation has been increasingly used for the treatment of primary and metastatic hepatic tumors as an alternative or adjunct to surgical resection .
although rfa is a safe modality overall , rfa is associated with minor and major complication rates of 9% ( 9 ) .
biliary complications , including stricture and leakage , are relatively uncommon , with a prevalence of 1% ( 9 ) .
a bbf as a complication of rfa is extremely rare , with only seven cases reported worldwide ( table 1 ) ( 5 - 10 ) . to the best of our knowledge , no patient with a bbf that occurred after rfa has undergone successful percutaneous drainage leading to complete blockage of the fistula .
thus , the present case is the first report of bbf due to rfa that was successfully managed by percutaneous drainage and safe removal of the catheter .
a bbf due to rfa may be caused by rupture of a growing biloma into a diaphragmatic defect caused by thermal injury , a finding supported by our imaging results .
the proximity of a tumor to the lung base could cause thermal injury to the diaphragm following rfa , and symptomatic biloma formation may develop in patients with large tumors owing to more severe bile duct damage ( 8) . the ablated tumor in our patient was located in the hepatic dome adjacent to the right diaphragm , although the tumor was not large . as described in the present case , clinical findings for a bbf include pneumonitis , fever , chest pain , right upper abdominal pain and cough productive of bile - stained sputum , known as bilioptysis ( 8) .
plain chest radiographs often show abnormal findings and may demonstrate right pleural effusion , right basilar atelectasis or the presence of a lung abscess .
a ct scan can be used to identify both hepatic abscesses and air within the biliary tree , but images will not delineate a fistulous tract .
endoscopic retrograde cholangiography or percutaneous transhepatic cholangiography will adequately demonstrate the presence of a bbf ( 3 , 4 ) . in our patient
, we were able to identify the fistula tract with tubography after percutaneous drainage . to date
traditionally , the definitive treatment for a bbf has involved extensive surgery , with or without simple drainage of the subdiaphragmatic abscess and resection of the fistulous tract ( 2 ) .
the conservative approach that has been reported most frequently has involved the use of endoscopic sphincterotomy with removal of any stones or sludge , followed by stent placement in the common bile duct ( 3 , 5 ) .
reduction of the pressure gradient between the common bile duct and the duodenum may lead to preferential drainage of bile through the stent , which then has a lower pressure than the fistula .
percutaneous drainage for a bbf not related to rfa has been previously described ( 4 ) . in patients with a bbf complicated with liver abscess , as in our patient , external drainage of an abscess or biloma
can facilitate both alleviation of hepatic inflammation and the pressure gradient across the biliary tract and bronchial tree . in all of the previous cases , patients with a bbf following rfa complicated by a biloma or liver abscess underwent external drainage with or without endoscopic drainage ( 6 , 8 , 10 ) .
we found that an initial five weeks of percutaneous drainage plus antibiotic therapy was insufficient to clear the fistula tract .
hence , long - term drainage maintenance with antibiotics after symptomatic improvement is likely to be required for complete remission of a bbf . in summary , although rfa is a safe and effective modality for the treatment of hcc , the procedure should be performed with caution to prevent bbf formation in patients with liver dome tumors .
we report the first case of a bbf as a complication of rfa in a patient with hcc in the liver dome adjacent to the right diaphragm , which was successfully eliminated by percutaneous drainage and antibiotic treatment .
radiofrequency ablation ( rfa ) is a minimally invasive , image - guided procedure for the treatment of hepatic tumors . 
 while rfa is associated with relatively low morbidity , sporadic bronchobiliary fistulae due to thermal damage may occur after rfa , although the incidence is rare . 
 we describe a patient with a bronchobiliary fistula complicated by a liver abscess that occurred after rfa . 
 this fistula was obliterated after placement of an external drainage catheter into the liver abscess for eight weeks .