Imaging Diagnosis of Cystic Pancreatic Lesions: Pseudocyst versus Nonpseudocyst

Published Online:

Although the clinical, radiologic, and pathologic features of cystic pancreatic lesions are well known, preoperative diagnosis is difficult. Differentiation between a pancreatic pseudocyst and a cystic pancreatic neoplasm is crucial in determining the proper treatment. Careful evaluation of the patient’s clinical history is important for accurate diagnosis of a pseudocyst. Clinical scenarios include a pseudocyst developing after acute pancreatitis and a pseudocyst superimposed on chronic pancreatitis. However, a pseudocyst in a patient with no clinical history of pancreatitis poses a diagnostic problem. The differential diagnosis of a neoplastic cystic lesion of the pancreas includes serous cystadenoma, mucinous cystic neoplasms, intraductal papillary mucinous tumor, and solid and papillary epithelial neoplasm. Definitive diagnosis is often possible when the lesion has a typical radiologic appearance, but in many cases characterization with imaging alone is impossible. Thin-section computed tomography with multiplanar reformation, magnetic resonance cholangiopancreatography, and endoscopic ultrasonography have emerged as modalities that can provide additional diagnostic information. Familiarity with the range of imaging appearances and awareness of the diagnostic strengths and limitations of each imaging modality are important for accurate diagnosis and management of cystic pancreatic lesions.

© RSNA, 2005


  • 1 FriedmanAC, Lichtenstein JE, Dachman AH. Cystic neoplasms of the pancreas: radiological-pathological correlation. Radiology1983; 149: 45–50. LinkGoogle Scholar
  • 2 Fernandez-del CastilloC, Targarona J, Thayer SP, Rattner DW, Brugge WR, Warshaw AL. Incidental pancreatic cysts: clinicopathologic characteristics and comparison with symptomatic patients. Arch Surg2003; 138: 427–433. Crossref, MedlineGoogle Scholar
  • 3 WarshawAL, Rutledge PL. Cystic tumors mistaken for pancreatic pseudocysts. Ann Surg1987; 205: 393–398. Crossref, MedlineGoogle Scholar
  • 4 CurryCA, Eng J, Horton KM, et al. CT of primary cystic pancreatic neoplasms: can CT be used for patient triage and treatment? AJR Am J Roentgenol2000; 175: 99–103. Crossref, MedlineGoogle Scholar
  • 5 BoundsBC, Brugge WR. EUS diagnosis of cystic lesions of the pancreas. Int J Gastrointest Cancer2001; 30: 27–31. Crossref, MedlineGoogle Scholar
  • 6 BradleyEL 3rd. A clinically based classification system for acute pancreatitis: summary of the International Symposium on Acute Pancreatitis, Atlanta, Ga, September 11 through 13, 1992. Arch Surg1993; 128: 586–590. Crossref, MedlineGoogle Scholar
  • 7 BalthazarEJ, Ranson JH, Naidich DP, Megibow AJ, Caccavale R, Cooper MM. Acute pancreatitis: prognostic value of CT. Radiology1985; 156: 767–772. LinkGoogle Scholar
  • 8 BalthazarEJ, Freeny PC, vanSonnenberg E. Imaging and intervention in acute pancreatitis. Radiology1994; 193: 297–306. LinkGoogle Scholar
  • 9 RansonJH. Etiological and prognostic factors in human acute pancreatitis: a review. Am J Gastroenterol1982; 77: 633–638. MedlineGoogle Scholar
  • 10 YeoCJ, Bastidas JA, Lynch-Nyhan A, Fishman EK, Zinner MJ, Cameron JL. The natural history of pancreatic pseudocysts documented by computed tomography. Surg Gynecol Obstet1990; 170: 411–417. MedlineGoogle Scholar
  • 11 FerrucciJT 3rd, Mueller PR. Interventional approach to pancreatic fluid collections. Radiol Clin North Am2003; 41: 1217–1226. Crossref, MedlineGoogle Scholar
  • 12 BalthazarEJ. Complications of acute pancreatitis: clinical and CT evaluation. Radiol Clin North Am2002; 40: 1211–1227. Crossref, MedlineGoogle Scholar
  • 13 KhuranaB, Mortele KJ, Glickman J, Silverman SG, Ros PR. Macrocystic serous adenoma of the pancreas: radiologic-pathologic correlation. AJR Am J Roentgenol2003; 181: 119–123. Crossref, MedlineGoogle Scholar
  • 14 Cohen-ScaliF, Vilgrain V, Brancatelli G, et al. Discrimination of unilocular macrocystic serous cystadenoma from pancreatic pseudocyst and mucinous cystadenoma with CT: initial observations. Radiology2003; 228: 727–733. LinkGoogle Scholar
  • 15 BuetowPC, Rao P, Thompson LD. Mucinous cystic neoplasms of the pancreas: radiologic-pathologic correlation. RadioGraphics1998; 18: 433–449. LinkGoogle Scholar
  • 16 FukukuraY, Fujiyoshi F, Sasaki M, Inoue H, Yonezawa S, Nakajo M. Intraductal papillary mucinous tumors of the pancreas: thin-section helical CT findings. AJR Am J Roentgenol2000; 174: 441–447. Crossref, MedlineGoogle Scholar
  • 17 LimJH, Lee G, Oh YL. Radiologic spectrum of intraductal papillary mucinous tumor of the pancreas. RadioGraphics2001; 21: 323–337; discussion 337–340. LinkGoogle Scholar
  • 18 KoitoK, Namieno T, Ichimura T, et al. Mucin-producing pancreatic tumors: comparison of MR cholangiopancreatography with endoscopic retrograde cholangiopancreatography. Radiology1998; 208: 231–237. LinkGoogle Scholar
  • 19 GongJS, Xu JM. Role of curved planar reformations using multidetector spiral CT in diagnosis of pancreatic and peripancreatic diseases. World J Gastroenterol2004; 10: 1943–1947. Crossref, MedlineGoogle Scholar
  • 20 FukukuraY, Fujiyoshi F, Hamada H, et al. Intraductal papillary mucinous tumors of the pancreas: comparison of helical CT and MR imaging. Acta Radiol2003; 44: 464–471. Crossref, MedlineGoogle Scholar
  • 21 HernandezLV, Mishra G, Forsmark C, et al. Role of endoscopic ultrasound (EUS) and EUS-guided fine needle aspiration in the diagnosis and treatment of cystic lesions of the pancreas. Pancreas2002; 25: 222–228. Crossref, MedlineGoogle Scholar
  • 22 LewandrowskiKB, Southern JF, Pins MR, Compton CC, Warshaw AL. Cyst fluid analysis in the differential diagnosis of pancreatic cysts: a comparison of pseudocysts, serous cystadenomas, mucinous cystic neoplasms, and mucinous cystadeno-carcinoma. Ann Surg1993; 217: 41–47. Crossref, MedlineGoogle Scholar
  • 23 SandJA, Hyoty MK, Mattila J, Dagorn JC, Nordback IH. Clinical assessment compared with cyst fluid analysis in the differential diagnosis of cystic lesions in the pancreas. Surgery1996; 119: 275–280. Crossref, MedlineGoogle Scholar

Article History

Published in print: May 2005