Incidentally detected biliary ductal dilatation on contrast-enhanced CT: what is the incidence of occult obstructing malignancy?

  • James S. Chalfant
  • Alton W. Skaggs
  • Thomas W. Loehfelm
  • Ghaneh Fananapazir
  • Michael T. CorwinEmail author



The purpose of this study was to determine the incidence of occult obstructing malignancy in the setting of asymptomatic biliary ductal dilatation incidentally detected and without identifiable cause on contrast-enhanced CT.


A retrospective search identified patients with biliary ductal dilatation on contrast-enhanced CT from March 30, 2007 to November 1, 2017. Patients with biliary symptomatology or clinical concern for an obstructing process, an explanation for biliary ductal dilatation on index CT, intrahepatic without extrahepatic biliary ductal dilatation, concurrent pancreatic ductal dilatation, and inadequate follow-up were excluded. A reference standard of at least 1 year of imaging follow-up or 2 years of clinical follow-up was used to exclude occult obstructing malignancy.


156 patients were included; 120 patients met imaging follow-up criteria and 36 patients met clinical follow-up criteria. No cases of occult malignancy were identified as the source of biliary ductal dilatation (95% CI 0.0–1.9%). LFTs were available for 131 patients, of which 36 were elevated (27%). One case demonstrated a 1.2-cm ampullary adenoma on endoscopic retrograde cholangiopancreatography (occult on follow-up MRI, normal LFTs at the time of the index CT).


Asymptomatic biliary ductal dilatation incidentally detected and without identifiable cause on contrast-enhanced CT is likely benign in patients with normal LFTs, and further workup may not be warranted.


Biliary ductal dilation Incidental Malignancy Bile ducts 



  1. 1.
    Atkinson CJ, Lisanti CJ, Schwope RB, et al. Mild asymptomatic intrahepatic biliary dilation after cholecystectomy, a common incidental variant. Abdom Radiol (NY) 2017; 42(5):1408-1414CrossRefGoogle Scholar
  2. 2.
    Sebastian S, Araujo C, Neitlich JD, Berland LL. Managing incidental findings on abdominal and pelvic CT and MRI, Part 4: white paper of the ACR Incidental Findings Committee II on gallbladder and biliary findings. J Am Coll Radiol 2013; 10(12):953-956CrossRefGoogle Scholar
  3. 3.
    Bruno M, Brizzi RF, Mezzabotta L, et al. Unexplained common bile duct dilatation with normal serum liver enzymes: diagnostic yield of endoscopic ultrasound and follow-up of this condition. J Clin Gastroenterol 2014; 48(8):e67-70CrossRefGoogle Scholar
  4. 4.
    Malik S, Kaushik N, Khalid A, et al. EUS yield in evaluating biliary dilatation in patients with normal serum liver enzymes. Dig Dis Sci 2007; 52(2):508-512CrossRefGoogle Scholar
  5. 5.
    Park JS, Lee DH, Jeong S, Cho SG. Determination of diameter and angulation of the normal common bile duct using multidetector computed tomography. Gut Liver 2009; 3(4):306-310CrossRefGoogle Scholar
  6. 6.
    Peng R, Zhang L, Zhang XM, et al. Common bile duct diameter in an asymptomatic population: A magnetic resonance imaging study. World J Radiol 2015; 7(12):501-508CrossRefGoogle Scholar
  7. 7.
    Senturk S, Miroglu TC, Bilici A, et al. Diameters of the common bile duct in adults and postcholecystectomy patients: a study with 64-slice CT. Eur J Radiol 2012; 81(1):39-42CrossRefGoogle Scholar
  8. 8.
    Berland LL, Silverman SG, Gore RM, et al. Managing incidental findings on abdominal CT: white paper of the ACR incidental findings committee. J Am Coll Radiol 2010; 7(10):754-773CrossRefGoogle Scholar
  9. 9.
    Kim JE, Lee JK, Lee KT, et al. The clinical significance of common bile-duct dilatation in patients without biliary symptoms or causative lesions on ultrasonography. Endoscopy 2001; 33(6):495-500CrossRefGoogle Scholar
  10. 10.
    Rana SS, Bhasin DK, Sharma V, Rao C, Gupta R, Singh K. Role of endoscopic ultrasound in evaluation of unexplained common bile duct dilatation on magnetic resonance cholangiopancreatography. Ann Gastroenterol 2013; 26(1):66-70Google Scholar
  11. 11.
    Tamir S, Braun M, Issachar A, Bachar GN, Benjaminov O. Yield of magnetic resonance cholangiopancreatography for the investigation of bile duct dilatation in asymptomatic patients. United European Gastroenterol J 2017; 5(3):408-414CrossRefGoogle Scholar
  12. 12.
    Baker HL, Caldwell DW. Lesions of the ampulla of Vater. Surgery 1947; 21(4):523-531.Google Scholar
  13. 13.
    Sato T, Konishi K, Kimura H, et al. Adenoma and tiny carcinoma in adenoma of the papilla of Vater–p53 and PCNA. Hepatogastroenterology 1999; 46(27):1959-1962Google Scholar
  14. 14.
    Chini P, Draganov PV. Diagnosis and management of ampullary adenoma: The expanding role of endoscopy. World J Gastrointest Endosc 2011; 3(12): 241–247CrossRefGoogle Scholar
  15. 15.
    Martin JA, Haber GB. Ampullary adenoma: clinical manifestations, diagnosis, and treatment. Gastrointest Endosc Clin N Am 2003; 13(4):649-669CrossRefGoogle Scholar
  16. 16.
    Chathadi KV, Khashab MA, Acosta RD, et al. The role of endoscopy in ampullary and duodenal adenomas. Gastrointest Endosc 2015; 82(5):773-781CrossRefGoogle Scholar
  17. 17.
    Espinel J, Pinedo E, Ojeda V, Del Rio MG. Endoscopic management of adenomatous ampullary lesions. World J Methodol 2015; 5(3):127-135CrossRefGoogle Scholar
  18. 18.
    Yeh BM, Liu PS, Soto JA, Corvera CA, Hussain HK. MR imaging and CT of the biliary tract. Radiographics 2009; 29(6):1669-1688CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • James S. Chalfant
    • 1
  • Alton W. Skaggs
    • 2
  • Thomas W. Loehfelm
    • 1
  • Ghaneh Fananapazir
    • 1
  • Michael T. Corwin
    • 1
    Email author
  1. 1.Department of Radiology, Davis Medical CenterUniversity of CaliforniaSacramentoUSA
  2. 2.School of MedicinemUniversity of CaliforniaSacramentoUSA

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