Presentation on theme: "Solid Pseudopapillary Tumor of the Pancreas: Diagnosis with CT and MRI"— Presentation transcript:
1Solid Pseudopapillary Tumor of the Pancreas: Diagnosis with CT and MRI Mengsu Zeng, Xiuzhong Yao曾蒙苏 姚秀忠Department of Radiology, Zhongshan Hospital of Fudan University and Department of Medical Image, Shanghai Medical College of Fudan university, Shanghai, China
2BackgroundWith the increasing radiological reports of Solid pseudopapillary tumor of the pancreas, its typical imaging features have been well known to radiologists.However, with the improvement in the imaging modalities and widespread use of CT and MRI, those atypical neoplasms have been becoming more and more common.
5The purpose of this study was to investigate the accuracy of CTand MRI for diagnosis of solidpseudopapillary tumor of the pancreas(SPTP).
6Material and Methods 39 patients with SPTP proven by histopathology were divided into the correct diagnosis andmisdiagnosis group based on the preoperativeimaging and histopathologic results.All CT and MR imaging signs, including gender,age, tumor size, modalities (CT or MRI), location,shape, capsule, cystic degeneration, hemorrhage,calcification and enhancement type, wereretrospectively evaluated with a correlation to theirpathologic findings and statistically analyzed.
7Results Among 39 imaging cases, 15 (38.5%) misdiagnosed (mean age years old)24(61.5%) diagnosed. (mean age years old, p=0.000).Tumor size tended to be smaller in the elder group and had a negative linear correlation with the patient age (r=-0.408, p=0.025).cause of higher misdiagnosis: correctly diagnosis :the older patients (p=0.007), gender,small tumors (p=0.037), location,CT (p=0.049) shape,non-hemorrhage (p=0.000) capsule,cystic degeneration,calcificationtype of enhancement .Macroscopically, large SPTPs were more likely to appear the capsule (p=0.002),cystic degeneration (p=0.003)and hemorrhage (p=0.029) than small tumors.
8Results N Mean (cm) P value size misdiagnosis 15 5.0000 0.289 24 Table 1 Comparison of tumor size and age between two groupsNMean (cm)P valuesizemisdiagnosis155.00000.289Correct diagnosis246.1167age0.000
9ResultsGraph 1 Linear regression analysis of tumor size and patient ageNote: Bconstant=7.435, p=0.000; Bage=-0.067, p=0.025
11Results Table 3 Tumors’ demonstrations between CT and MRI Findings CT P valueCapsulePresence14Absence920.086Cystic degeneration12131130.093hemorrhage12250.000calcification8150.028gradual enhancement210.547
12Table 4 Histopathological analysis in tumor size and patient age ResultsTable 4 Histopathological analysis in tumor size and patient ageFindingsSize GroupP valueAge GroupLargeSmallThe elderThe youngerCapsulePresence231717Absence350.0020.116Cystic degeneration22640.0030.049hemorrhage181480.0290.150calcification21.000
13Fig. 1.—23-year-old woman with a typical solid pseudopapillary tumor of pancreas Fig. 1a(a) Photograph of gross surgical specimen demonstrates the fibrous capsule, hemorrhagic areas and cystic degeneration.
14Fig. 1bFig. 1cFig. 1.—23-year-old woman with a typical solid pseudopapillary tumor of pancreas(b, c) T2 weighted image and T1 weighted image with fat suppression showed the typical imaging features: the capsule, cystic degeneration and hemorrhagic areas.
15Fig. 1eFig. 1d(d, e,f) Dynamic contrast-enhanced MR scans revealed the early peripheral enhancement with progressively fill in and delayed enhancement of the capsule.Fig. 1f
16Fig. 2.—19-year-old woman with a solid pseudopapillary tumor of pancreas misdiagnosed as mucinous cystic adenocarcinoma.Fig. 2a(a) Photograph of gross surgical specimen demonstrated the septations among chamberlets with cystic degeneration and the incomplete pseudocapsule.
17Fig. 2bFig. 2c(b, c,d) Dynamic contrast-enhanced CT scans demonstrated the pseudoseptate type enhancement and contrast medium was progressively filled in from the septation and margin to the centre of tumors.Fig. 2d
18Fig. 3 —51-year-old man with a small solid pseudopapillary tumor of pancreas. Fig. 3a(a) Photograph of gross surgical specimen demonstrated a small solid tumor with the thick and irregular rim.
19Fig. 3bFig. 3c(b) Axial T1-weighted image reveals the tumor’s rim with hyperintense and the solid portions with homogeneous hypointense.(c, d) The small tumor appeared imperceptible in the contrast-enhanced T1-weighted and CT images on the delayed phase.Fig. 3d
20Fig. 4—49-year-old woman with a solid pseudopapillary tumor of pancreas misdiagnosed as an inflammatory mass.Fig. 4a(a) Photograph of gross surgical specimen demonstrated a relatively large solid tumor without pseudocapsule and hemorrhagic areas.
21(b) Axial unenhanced CT showed Fig. 4cFig. 4b(b) Axial unenhanced CT showedthe swelling pancreatic head with isodensity.(c, d), Dynamic contrast-enhanced CT scans displayed a large tumor with markedly early and delayed enhancement in the pancreatic head.Fig. 4d
22ConclusionTo avoid misdiagnosis, it should be very careful to evaluate some characteristic imaging signs in small tumors and those occurred to the aged. Compared to CT, MR was much superior to avoid misdiagnosis of SPTP.