Biliary Cystic Tumors Research Articles

Hepatic hemangioma in a simple liver cyst mimicking biliary cystic neoplasm

BackgroundFollow-up is recommended for an asymptomatic unilocular hepatic cystic lesion without wall-thickness and nodular components. A few liver cystic lesions represent biliary cystic neoplasms, which are difficult to differentiate from simple cysts with benign mural nodules on imaging alone.Case presentationAn 84-year-old woman with a history of simple liver cyst diagnosed one year prior was admitted for evaluation of a developed mural nodule in the cystic lesion. She had no specific symptoms and no abnormalities in blood tests except for carcinoembryonic antigen (5.0 ng/mL) and carbohydrate antigen (43.5 U/mL) levels. Contrast-enhanced computed tomography revealed a well-defined, low-attenuation lesion without a septum that had enlarged from 41 to 47 mm. No dilation of the bile duct was observed. A gradually enhancing mural nodule, 14 mm in diameter, was confirmed. MRI revealed a uniform water-intense cystic lesion with a mural nodule. This was followed by T2-enhanced imaging showing peripheral hypointensity and central hyperintensity. Enhanced ultrasonography revealed an enhanced nodule with a distinct artery within it. A needle biopsy of the wall nodule or aspiration of intracystic fluid was not performed to avoid tumor cell spillage. The possibility of a neoplastic cystic tumor could not be ruled out, so a partial hepatectomy was performed with adequate margins. Pathologically, the cystic lesion contained a black 5 mm nodule consisting of a thin, whitish fibrous wall and dilated vessels lined by CD31 and CD34 positive endothelial cells. The final diagnosis was a rare cavernous hemangioma within a simple liver cyst.ConclusionsCavernous hemangiomas mimicking well-enhanced mural nodules can arise from simple liver cysts. In less malignant cases, laparoscopic biopsy or percutaneous targeted biopsy of the mural nodules, together with needle ablation, may be recommended to avoid unnecessary surgery.

Clinicopathological features and management of biliary cystic tumors of the liver: a single-center experience

BackgroundBiliary cystic neoplasms (BCNs) of the liver are rare pathologies encountered in hepatobiliary surgeries. Till now, there is a lack of definitive criteria used to differentiate biliary cystadenoma (BCA) from biliary cystadenocarcinoma (BCAC).MethodsIn the period between 2005 and 2018, the data of consecutive patients diagnosed with BCA and BCAC were retrospectively reviewed.ResultsA total of 62 patients underwent surgical management for BCNs. BCA was diagnosed in 50 patients while 12 patients had BCAC. Old age, male gender, smoking, and abdominal pain were strongly associated with BCAC. Left lobe location, small size, with the presence of mural nodule, and solid component were significantly noticed with BCAC. A novel pre-operative score was developed to predict the susceptibility for BCAC and help us to identify the optimal surgical strategy. Blood loss, operative time, and complications were comparable between the two study groups.ConclusionMural nodules or solid components are suggestive of BCAC. Complete surgical resection of cystic tumors of the liver is mandatory due to malignant potential of the lesion and for prolonged survival.

Benign Diseases Masquerading as Cholangiocarcinoma: Can we Differentiate before Surgery?

Background: Cholangiocarcinoma (CCA) is a potentially lethal disease that requires surgical treatment. There are many benign conditions, those that do not require surgical treatment, displaying imaging characteristics that resemble CCA, leading to therapeutic misadventures. This study aimed to evaluate the proportion of benign conditions that underwent hepatic resection for presumed CCA, and explore the differences between the characteristics of these two entities stratified by primary imaging features of the lesions. Methods: This retrospective study ran between January 2004 and December 2011. We reviewed the pathological records of all 1,402 patients who underwent curative-intent hepatic resection for preoperatively diagnosed CCA. All clinical and pathological parameters were analyzed. Results: The proportion of benign conditions that underwent hepatic resection was 3.78% (53/1,402). For mass-forming lesions, CCA was associated with higher age, alkaline phosphatase, tumor markers, neutrophil to lymphocyte ratio, and mass size. The patients with mass-forming benign conditions were more associated with diabetes mellitus. For lesions with bile duct dilatation, intraductal tumor, including CCA, had higher CA19-9 level and NLR with statistical significance. For cystic lesions, biliary cystic neoplasm had statistical significance in the rate of abdominal pain. Conclusions: The proportion of hepatic resection for benign conditions was quite low. There were many characteristic differences used to differentiate benign mass-forming conditions from CCA, whereas only few markers in the setting of cystic lesions and biliary dilatation. We recommend performing standard hepatic resection in every case, regardless of the type of imaging features, if the lesion has a chance of being CCA.

About an unusual biliary cystic liver tumor

A 74-year-old woman presented atypical generalized abdominal pain for several months. She previously was cured of breast cancer a decade ago. Physical examination revealed an abdominal deformity of the right quadrant with hepatomegaly. She did not report any loss of weight or asthenia. Blood tests were normal, especially liver function. Tumors markers (carcinoembryonic antigen, alfa-fetoprotein, carbohydrate antigen 19-9 and 15-3) were strictly normal.

1428 Biliary Obstruction Due to Extrahepatic Biliary Mucinous Cystic Neoplasm: An Uncommon Case

INTRODUCTION: Biliary mucinous cystic neoplasms (BMCNs) are a rare form of premalignant biliary cystic tumors, much like their better-known counterpart, biliary intraductal papillary mucinous neoplasms (IPMNs). BMCNs most commonly occur in females during the 5th decade of life. They account for approximately 1-5% of all liver cysts. The lack of awareness of these lesions poses a challenge for proper and timely diagnosis. Here, we present an interesting case of extrahepatic BMCN. CASE DESCRIPTION/METHODS: A 30-year-old female presented with pruritis, dark urine, and light-colored stools. Labs revealed transaminitis and elevated bilirubin concerning for biliary obstruction. Abdominal ultrasound showed cholelithiasis and dilation of the distal common bile duct (CBD) concerning for choledocholithiasis. MRCP was performed and described a 2.2 × 2.4 cm cystic dilatation of the extrahepatic bile duct involving the distal common hepatic duct (CHD) concerning for either type 1B or type II choledochal cyst. Endoscopic ultrasound revealed a CHD cystic lesion with internal debris concerning for either sludge or biliary IPMN (Figure 1). ERCP with cholangioscopy revealed papillary projection in the CHD (Figure 2). Directed biopsies revealed mucinous epithelium with cytologic atypia. The patient was referred for complete resection of the CBD and CHD, cholecystectomy, and Roux-en-Y hepaticojejunostomy. Surgical pathology revealed a tumor consisting of a cystic structure lined by mucinous epithelium with estrogen receptor (ER) positive ovarian-type stroma, and mild to focal moderate dysplasia, consistent with noninvasive extrahepatic BMCN (Figure 3). DISCUSSION: BMCNs are often detected incidentally when investigating other common causes of biliary disease. The overall incidence of BMCNs is approximately 1:20,000 to 1:100,000. They are most commonly found within the liver (90%), are rarely extra-hepatic, and they seldom present with obstructive jaundice. The treatment of choice is surgical resection. Diagnosis is made via histological confirmation of ovarian-type stroma. The location of the lesion, in this case, is more common for IPMNs. Both IPMNs and BMCNs carry malignant potential requiring complete resection for diagnosis and treatment. With the risk of malignant transformation as high as 30%, an awareness of these rare neoplasms is very important.

Premalignant Lesions of the Biliary Tract.

Although the most common presentation of biliary disorder in North America is secondary to gallstone disease, an awareness of benign biliary cystic neoplasms is important because of the risk of malignant transformation. The incidence of premalignant cystic neoplasms of the bile duct is not well characterized and they often are detected incidentally for suspicion of other abdominal disorders. This article describes the 4 most common premalignant biliary cystic neoplasms: biliary mucinous cystic neoplasms, intraductal papillary mucinous neoplasms of the bile duct, intraductal tubular papillary neoplasms of the bile duct, and choledochal cysts.

Biliary cystadenoma: An unusual cause of recurrent cholangitis

Biliary cystic neoplasm is a rare variety of liver cyst. Cystobiliary communication is even more uncommon. Biliary complications from cystobiliary communication can mimic liver hydatid disease, particularly in endemic areas. A middle‐aged female presented with recurrent cholangitis and a cystic lesion in the liver, which ultimately turned to be a biliary cystadenoma. We report on this case for its rarity.

Laparoscopic resection of biliary cystic tumours

Introduction: Biliary cystic neoplasms are rare tumours of the biliary tract. These are often confused with other cystic lesions such a hydatid cysts and simple cysts. Surgery is necessary owing to malignant potential. Method: Retrospectve analysis of 6 patients operated with a diagnosis of biliary cystic neoplasm subjected to laparoscopic surgery. All were female. One was previously deroofed as a hydatid cyst, four presented with pain and one as acute pancreatitis and one incidentally diagnosed on sonography. Mean age was 48 years. Result: Five of the lesions were in segment 4b and 5 and one in segment 3 . Size varied from 7 cm to 23 cm in maximum diameter. Laparoscopic resection was successfully completed in all six patients, no transfusion was required. The was one bile leak requiring temporary biliary stent. One was biliary IPMN, four were biliary cyst adenoma. In one biliary epithelium could not be demonstrated in a large complex cyst. One patient had hernia from specimen extraction site and the patient with IPMN-B required subsequent Whipples procedure for ampullary focus of tumour detected subsequently, following a laparoscopic left hepatectomy. There are no recurrences over a median follow up of 3 years. Conclusion: Biliary cystic neoplasms are rare intrahepatic tumours which can be safely managed laparoscopically

Simple Hepatic Cysts Mimicking Biliary Cystic Neoplasm after Ultrasound-Guided Percutaneous Alcohol Sclerotherapy

Simple Hepatic Cysts Mimicking Biliary Cystic Neoplasm after Ultrasound-Guided Percutaneous Alcohol Sclerotherapy

Value of multi-phase enhanced MRI combined with histogram analysis of apparent diffusion coefficient in differential diagnosis of intrahepatic biliary cystadenoma and intrahepatic biliary cystadenocarcinoma

Objective To investigate the value of quantitative multi-phase enhanced MRI combined with histogram analysis of ADC in differential diagnosis of intrahepatic biliary cystadenoma (HBCA) and intrahepatic biliary cystadeno carcinoma (HBCAC). Methods Twenty-five patients with pathologically confirmed intrahepatic biliary cystic tumor (HBCT), including 16 cases of HBCA and 9 cases of HBCAC, were retrospectively analyzed. All the patients underwent upper abdominal MR plain scan and multi-phase enhanced scan. The MRI findings of the lesions were observed. The peak contrast enhancement ratio (pCER) of the lesions in the arterial phase, portal venous phase and delayed phase was calculated. ADC histogram analysis was performed and the quantitative parameters were acquired, including the average, standard deviation, median, kurtosis, skewness, and the 10th, 30th,70th, 90th percentile. Qualitative parameters were compared using Fisher exact test. The continuous variables with normal distribution and homogeneous variance were compared by independent sample t test. The continuous variables with skewed distribution were compared by Mann-Whitney U test. The ROC curve analysis was used to evaluate the differential diagnostic ability of the variables with significant differences between HBCA and HBCAC patients. Results There was a statistically significant difference between HBCA and HBCAC in terms of gender, age and whether there was bile duct dilatation or mural nodules (all P 0.05). The pCER of arterial phase, portal venous phase and delayed phase of HBCAC patients were higher than those of HBCA patients (all P<0.05).The standard deviation of ADC value of HBCAC group was higher than that of HBCA group, while the kurtosis and the 10th percentile were lower than those of HBCA group, and the differences were statistically significant between the two groups (all P<0.05). When the 10th percentile value of ADC histogram was ≤ 2.060×10-3 mm2/s, the area under the ROC curve of discriminating between HBCA and HBCAC was the largest (0.861), and the diagnostic accuracy, sensitivity and specificity were 84.0% and 77.8% and 87.5%, respectively. Conclusion Quantitative multi-phase enhanced MRI combined with histogram analysis of ADC had certain value for the differential diagnosis of HBCA and HBCAC, and the 10th percentile of the ADC histogram had the best diagnostic efficiency. Key words: Bile duct neoplasms; Magnetic resonance imaging; Diffusion weighted imaging; Histogram

Mucinous cholangiocarcinoma: Clinicopathological features of the rarest type of cholangiocarcinoma.

Mucinous cholangiocarcinoma is extremely rare and its clinicopathological features remain unclear. The present study aimed to analyze published data on mucinous cholangiocarcinoma. Medical databases were searched from 1980 to 2016, and clinicopathological data for 16 mucinous cholangiocarcinoma patients were obtained. Characteristic imaging findings, including hypovascular tumor with peripheral enhancement on computed tomography and angiography, extremely high intensity on T2‐weighted magnetic resonance images, intratumoral calcification and luminal communication between the tumor and bile duct on cholangiography, were noted. Mucinous cholangiocarcinoma was correctly diagnosed in one patient only, with some patients diagnosed as low‐malignant biliary cystic tumors preoperatively. Five cases were followed up after the first medical examination, and three of these were initially diagnosed as biliary cystadenoma or intraductal papillary neoplasm of the bile duct. All five tumors showed marked enlargement within 4 months of follow up. Macroscopically, the resected tumors were non‐cystic/solid in seven cases, and cystic in seven. Tumor diameter ranged from 5 cm to 22 cm, and mucoid cut surface, lobulation, lack of capsule and papillary growth were observed. Microscopically, co‐existing intraductal papillary neoplasm of the bile duct was noted in three of five patients with available data. Nine of 10 cases in whom the pathological stage was reported had advanced disease with lymph node and/or distant metastasis, and 5‐year survival was achieved in one microinvasive case only. Overall 1‐ and 3‐year survival rates were 60.1% and 40.1%, respectively. The possibility of mucinous cholangiocarcinoma should be considered when biliary cystic tumors are detected on imaging modalities, despite the rarity of this tumor.

A giant and insidious subphrenic biloma formation due to gallbladder perforation mimicking biliary cystic tumor: A case report.

Gallbladder perforation (GBP) represents a rare, but potentially life-threatening, complication of acute cholecystitis. GBP is subdivided into three categories whereas the development of biloma is extremely rare. The present case study reports on a 40-year-old man with a 10-year history of calculus cholecystitis, who was referred to The First Affiliated Hospital of Nanjing Medical University (Nanjing, China) for the surgical treatment of an emerging massive hepatic entity with insidious symptoms and normal laboratory tests. A preoperative imaging study demonstrated the collection with internal septations and mural nodules, but no visible communication with the biliary system. Given the suspected biliary cystic tumor, a laparotomy was performed and the lumen was scattered with papillae. An intraoperative frozen section examination illustrated a simple hepatic cyst. Biochemical analysis of the collection and histopathology of the gallbladder and capsule substantiated the diagnosis of biloma formation due to GBP. The purpose of the present case report was to demonstrate how a pinhole-sized perforation with extravasation of unconcentrated bile from the gallbladder may result in insidious clinical presentation and an undetected leak site. According to the clinicopathological characteristics and composition, formation of biloma should be classified as type IV GBP. To differentiate bilomas with intracystic septations and mural nodules from BCTs is difficult via a preoperative examination, and the definitive diagnosis should be based on a histological examination. Laparotomy with frozen section examination may be the optimal approach in such a case.

Biliary cystic neoplasms of the liver: An experience of 9 cases

Biliary cystic neoplasms of the liver: An experience of 9 cases

A case of biliary cystic tumor with repeated hemobilia.

Intraductal papillary neoplasm of the bile duct (IPNB) is classified as a biliary cystic tumor with a tendency of causing obstruction. Neoplastic cases involving hemobilia are rarely reported. We herein describe a case of biliary cystic tumor with repeated hemobilia. A 57-year-old woman was histologically diagnosed with cavernous hemangioma. During the follow-up period after transcatheter arterial embolization (TAE), she experienced repeated hemobilia, and multiple other TAE sessions were performed for hemostasis. She was referred to our hospital 8 years after the first surgery owing to a growing tumor. Histopathological examination after extended right hepatectomy and caudate lobectomy indicated IPNB with an associated invasive carcinoma. Six months thereafter, computed tomography revealed a recurrent liver tumor and a nodule in the abdominal cavity. She died 36 months after the second surgery, despite chemotherapy. Our experience suggests that IPNB should be considered during differential diagnosis of dilated hepatobiliary tumors with hemobilia.

Diagnosis and treatment of biliary cystic tumors

Biliary cystic tumors (BCTs) are rare cystic tumors and are accounted for less than 5% of liver cysts. BCTs are very common in middle-aged and elderly women, and depend on diagnosis of imaging including papillary projection or multilocular cystic liver mass. BCTs are frequently misdiagnosed due to the absence of specific diagnostic indicators, which should differentiate from diagnosis of hepatic cystic. Complete surgical resection is the first choice for BCTs with a good outcome, in addition to low recurrence. Once recurrence was identified in follow-up, BCTs can be treated by reoperation with a good outcome. Key words: Biliary cystadenoma; Biliary cystadenocarcinoma; Diagnosis; Therapy

Management of Biliary Cystic Tumors

To characterize clinical and radiological features associated with biliary cystic tumors (BCTs) of the liver, and to define recurrence-free and overall survival. Biliary cystadenoma (BCA) and biliary cystadenocarcinoma (BCAC) are rare tumors that arise in the liver. Between 1984 and 2013, 248 patients who underwent surgical resection of BCA or BCAC were identified. Clinical and outcome data were analyzed. Median total bilirubin, CA19-9, and carcinoembryonic antigen (CEA) levels were 0.6 mg/dL, 15.0 U/mL, and 2.7 ng/mL, respectively. Preoperative imaging included computed tomography only (62.5%), magnetic resonance imaging only (6.9%), or CT + MRI (18.5%). Features on cross-sectional imaging included multiloculation (56.9%), mural nodularity (16.5%), and biliary ductal dilatation (17.7%). The presence of these factors did not reliably predict BCAC versus BCA (sensitivity, 81%; specificity, 21%). Median biliary cyst size was 10.0 cm (interquartile range, 7-13 cm). Operative interventions included unroofing/partial excision of the lesion (14.1%), less than hemihepatectomy (48.8%), or hemi-/extended hepatectomy (36.3%). On pathology most lesions were BCA (89.1%), whereas 27 (10.9%) were BCAC. At last follow-up, there were 46 (18.3%) recurrences; 2 patients who initially had BCA recurred with BCAC. Median overall survival was 18.1 years; 1-year, 3-year, and 5-year survival was 95.0%, 86.8%, and 84.2%, respectively. Long-term outcomes were associated with BCAC versus BCA, as well as the presence of spindle cell/ovarian stroma (both P < 0.05). Among patients undergoing surgery for BCT, associated malignancy was uncommon (10%) and no preoperative findings reliably predicted underlying BCAC. After excision of BCA, long-term outcomes were good; however, patients with BCAC had a worse long-term prognosis.

Symptomatic and complicated nonhereditary developmental liver cysts: cross-sectional imaging findings

Commonly encountered in the general population, in the vast majority of cases nonhereditary developmental liver cysts are asymptomatic, not associated with altered hepatic function and confidently diagnosed on imaging studies, and do not require further workup, follow-up, or treatment. However, particularly in women, simple hepatic cysts may reach large sizes and cause symptoms and signs resulting from mass effect, vascular compression, and biliary obstruction. Furthermore, although rarely compared to the incidence observed in patients with adult polycystic kidney and liver disease, sporadic hepatic cysts sometimes undergo life-threatening complications such as intracystic hemorrhage, infection, or rupture, which require prompt imaging triage and appropriate interventional, laparoscopic, or open surgical treatment. This pictorial essay reviews with examples the cross-sectional imaging findings of symptomatic and complicated nonhereditary liver cysts, aiming to provide radiologists with an increased familiarity with these uncommon, challenging occurrences. Emphasis is placed on the role of MRI as a useful problem-solving modality to elucidate the complex imaging appearances resulting from intracystic bleeding and superinfection, and to differentiate complicated cysts from other hemorrhagic liver lesions and biliary cystic tumors.

A case of branch duct type intraductal papillary neoplasm of the bile duct treated by open surgery after 11 years of follow-up

The intraductal papillary neoplasm of the bile duct (IPNB) is a novel disease concept that was recently classified as a biliary cystic tumor by the revised World Health Organization classification. This is the case report of a 70-year-old female patient who experienced repeated episodes of obstructive jaundice and cholangitis since 2000, attributed to a mucus-producing hepatic tumor. Surgery was advised due to the repeated episodes; however, the patient refused. In May, 2011, the patient developed jaundice and fever and was treated with antibiotics. Since there was no improvement, the patient was admitted to the Tokyo Rosai Hospital. Abdominal computed tomography (CT) revealed a 50-mm cystic mass with an internal septum in the left hepatic lobe. Although the tumor size had remained almost unchanged compared to the initial CT scan performed in 2000, intra- and extra-hepatic bile duct dilation was more prominent on the second CT scan. Following admission, endoscopic retrograde cholangiopancreatography was performed and revealed an expanded papilla of Vater due to a mucous plug. A balloon catheter was inserted into the bile duct to remove the mucous plug, resulting in the drainage of copious amounts of mucus and infected bile. The patient finally consented to surgery and left hepatic lobectomy was performed. Consequently, the diagnosis of low-grade IPNB was made. Branch duct type IPNB, which is characterized by imaging appearance of a cystic mass and slow progression, is attracting increasing attention. In the present case, a cystic mass was identified in the left hepatic lobe, with no significant change in size after 11 years of follow-up, leading to the diagnosis of branch duct type IPNB. Considering the fact that IPNB is usually treated surgically at the time of diagnosis, the present case, due to the long-term follow-up, provides valuable insight into the natural history of the tumor.

Intraductal papillary neoplasm arising from peribiliary glands connecting with the inferior branch of the bile duct of the anterior segment of the liver

Intraductal papillary neoplasms of the bile duct are generally thought to arise from neoplastic papillary proliferation of epithelial cells lining the bile duct. We herein report a case with findings that strongly suggested that the biliary cystic tumor might have derived from a peribiliary gland. A 69-year-old female was found to have a cystic lesion with intracystic protrusions at the anterior segment of the right hepatic lobe and underwent hepatic anterior segment resection. Fluoroscopy of the resected specimen injected with contrast medium into the cyst revealed a connection between the cystic lesion and the bile ducts. The cyst was multilocular in appearance. On microscopic examination, the cyst was located within the portal tract of the inferior branch of the anterior segment and connected with the inferior branch of the bile duct. The wall of the hepatic cyst lacked an ovarian-like stroma. The tumor was composed of papillary and glandular components, and the tumor cells were similar to gastric foveolar and pyloric gland epithelia and regarded as adenoma. These tumor cells were positive for MUC 5AC, MUC6, and HIK1083. The tumor was finally diagnosed as an intraductal papillary neoplasm of the bile duct (adenoma, gastric type) arising from a peribiliary gland.

Cyst-Forming Intraductal Papillary Neoplasm of the Bile Ducts: Description of Imaging and Pathologic Aspects

Intraductal papillary neoplasm (IPN) of the bile duct is a newly described pathologic entity characterized by the presence of intraluminal tumors, which sometimes produce a large amount of mucin and form a cystic tumor. Cystic IPN of the bile duct is different from biliary cystadenoma or cystadenocarcinoma in that the former produces intraductal microscopic and macroscopic papillary tumors without ovarian-like stroma, whereas the latter produce a mucin-containing septate cystic tumor without communication with bile duct and with ovarian-like stroma in the cyst wall. The purpose of this study was to evaluate the potential relationships between cyst-forming IPNs of the bile duct and peribiliary glands and also intraductal papillary mucinous neoplasms of the pancreas. From a cohort of 87 patients with surgically resected and pathologically proved IPN of the bile duct, 12 patients with cystic IPN of the bile duct who underwent CT (n = 12), MRCP (n = 3), ultrasound (n = 3), and ERCP (n = 4) were included. Imaging findings were evaluated for the relationship of cystic tumors to the bile ducts; in particular, a diverticulum-like appearance was considered as suggestive of the peribiliary gland origin. Pathologic examination was conducted, and both gross and microscopic findings were recorded. Radiologic examination revealed aneurysm-like dilatation of the involved bile ducts in five patients and intrahepatic biliary cystic tumor in two patients. Interestingly, the remaining five patients had diverticulum-like cystic tumor with or without communication; one patient had a cystic tumor laterally attached to the extrahepatic bile duct. Histopathologically, cystic tumors are lined by atypical biliary epithelium showing intracystic papillary proliferation, with an appearance similar to that of pancreatic intraductal papillary mucinous neoplasm. This study suggests that cyst-forming IPN of the bile duct may be a biliary counterpart to pancreatic intraductal papillary mucinous neoplasm. In particular, at least some of the tumors seem to arise from peribiliary glands, and these cases might be a counterpart to branch-duct intraductal papillary mucinous neoplasm of the pancreas, given the histologic similarity between peribiliary glands and pancreatic branch ducts.