Learning objectives
1.
To describe the radiological findings of the three types of typical intraductal papillary mucinous neoplasm (IPMN);
Main Duct,Side Branch,Mixed.
2.
Highlight the features,
which distinguish IPMN from other cystic pancreatic lesions using radiologic-pathologic correlation.
3.
Provide a framework for work-up,
diagnosis,
follow-up and treatment of IPMNs.
Background
IPMNs are potentially malignant intraductal epithelial neoplasmsthat are composed of mucin-producing columnar cells.
These lesions show cyst formation,
papillary proliferation and varying degrees of atypia.
IPMNs can be classified into three types,
Main duct (MD-IPMN),
branch duct (BD-IPMN),
and mixed type,
based on imaging studies and histology.
They were first described in the 1980's [1],the incidence rate and natural history of IPMN are not fully known.IPMN is being recognized with increasing frequency around the world and the number of pancreatic resections for IPMN is rising...
Imaging findings OR Procedure details
Definition:
MD-IPMN is characterized by segmental or diffuse dilation of the main pancreatic duct (MPD) of>5mm without other causes of obstruction [3]. Fig. 1
Pancreatic cysts of >5mm in diameter that communicate with the MPD should be considered as BD-IPMN (pseudocyst is another consideration). Fig. 2,Fig. 4.
IPMNs usually present in older patients,
with a greater male predominance.
Imaging:
Ultrasonographic Findings: Ultrasound can show a septate cystic lesion and dilated MPD.
Not sufficient for diagnosis.
CT Findings:
BPD type: Lobulated multicystic wih thin,
irregular,
peripheral...
Conclusion
IPMN is a relatively new diagnosis,
and the natural history of the disease is not fully understood.
Despite the increase in familiarity with this lesion,
the incidence rate and natural history of IPMN remain unknown.
Therefore,
an aggressive approach to the treatment of IPMN is currently practiced.
This educational exhibit describes the different types of IPMN,
illustrated with radiological and pathological examples,
and provides information on the current guidelines for surveillance and treatment of these lesions.
References
Four cases of mucin-producing cancer of the pancreas on specific findings of the papilla of Vater.Ohhasi K,
Murakami Y,
Yakekoshi T,
et al
Prog Dig Endosc.1982;20:348–351.
Intraductal papillary mucinous neoplasms of the pancreas: an updated experience.Sohn TA,
Yeo CJ,
Cameron JL,
et al.
Ann Surg.2004;239:788–799.
International consensus guidelines 2012 for the management of IPMN and MCN of the pancreas.
Tanaka M,
Fernández-del Castillo C,
Adsay V,
Chari S,
Falconi M,
Jang JY,
Kimura W,
Levy P,
Pitman MB,
Schmidt CM,
et al.
Pancreatology.
2012 May-Jun;...