Journal article
Non-hyperfunctioning pancreatic endocrine tumors: multimodality imaging features with histopathological correlation
Abdominal imaging, Vol.40(7), pp.2398-2410
10/2015
DOI: 10.1007/s00261-015-0458-0
PMID: 25989932
Abstract
To evaluate the multimodality imaging features of non-hyperfunctioning pancreatic endocrine tumors (NF-PNET) with histopathological correlation.
Preoperative imaging (CT: n = 23; MRI: n = 14; (111)In-octreotide: n = 8) of 28 patients (17 female; mean age 55 years) with resected NF-PNET were evaluated for tumor location, size, morphology, attenuation/signal intensity, (111)In-octreotide uptake, cystic degeneration, and enhancement. Tissue specimens were assessed for the extent of stromal fibrosis, vascular density, presence of a fibrous pseudocapsule, and tumor grading. Correlation between imaging and histopathology was made using the Fisher-Freeman-Halton exact test.
NF-PNET arose from the pancreatic head/neck (n = 10), body (n = 7), and tail (n = 11). On CT, NF-PNET (mean largest diameter: 4.4 cm) appeared predominantly solid (69.6%), well defined (91.3%), and oval (47.8%) in shape. In the late arterial phase, NF-PNET appeared mainly hypovascular (55.5%). Septations (30.4%) and calcifications (21.7%) were relatively uncommon. On MRI, NF-PNET (mean size: 2.6 cm) appeared most commonly as solid (57.1%), encapsulated (71.4%), oval (64.2%) lesions that were hyperintense on T2-WI (64.3%), and hypo- or isovascular to pancreas (66.7%) during the late arterial phase. Cystic NF-PNET (3.8 cm) were not significantly larger than solid (3.5 cm) NF-PNET (CT, p = 0.758; MRI, p = 0.451). (111)In-octreotide uptake was demonstrated in 5/8 (62.5%) patients. At histopathology, NF-PNET were predominantly encapsulated (69.2%); stromal fibrosis comprised <33% of the tumor (69.2%), and vascular density was average (46.1%). A significant association was demonstrated between the degree of fibrosis and hypointensity on T2-WI (p = 0.003). Vascular density, tumor grade, and degree of fibrosis did not significantly relate to the pattern of enhancement.
NF-PNETs have variable imaging appearances but are most commonly oval shaped, solid, and well-defined/encapsulated masses, and hypovascular on late arterial and portal venous phase. Cystic degeneration in NF-PNET appears independent of tumor size. Low signal intensity on T2-WI correlates with extensive intratumoral fibrosis.
Details
- Title: Subtitle
- Non-hyperfunctioning pancreatic endocrine tumors: multimodality imaging features with histopathological correlation
- Creators
- Peter E Humphrey - Division of Abdominal Imaging and Intervention, Department of Radiology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA, 02115, USAFrancesco Alessandrino - Division of Body MRI, Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Ansin 224, Boston, MA, 02215, USAAndrew M Bellizzi - Department of Surgical Pathology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA, 02115, USAKoenraad J Mortele - Division of Body MRI, Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Ansin 224, Boston, MA, 02215, USA. kmortele@bidmc.harvard.edu
- Resource Type
- Journal article
- Publication Details
- Abdominal imaging, Vol.40(7), pp.2398-2410
- Publisher
- United States
- DOI
- 10.1007/s00261-015-0458-0
- PMID
- 25989932
- ISSN
- 0942-8925
- eISSN
- 1432-0509
- Grant note
- P50 CA174521 / NCI NIH HHS
- Language
- English
- Date published
- 10/2015
- Academic Unit
- Pathology
- Record Identifier
- 9984047711302771
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