European Radiology

, Volume 26, Issue 10, pp 3697–3705 | Cite as

Isoattenuating insulinomas at biphasic contrast-enhanced CT: frequency, clinicopathologic features and perfusion characteristics

  • Liang Zhu
  • Hua-dan Xue
  • Hao Sun
  • Xuan Wang
  • Yong-lan He
  • Zheng-yu Jin
  • Yu-pei Zhao
Computed Tomography



We aimed to determine the frequency of isoattenuating insulinomas, to investigate their clinicopathological features and to assess their regional pancreatic perfusion characteristics.


Institutional review board approval was obtained, and patient informed consent was waived. From July 2010 to June 2014, 170 patients (66 male, 104 female) with endogenous hyperinsulinemic hypoglycemia underwent biphasic contrast-enhanced CT before surgery, and 129 of those patients also received preoperative whole-pancreas CT perfusion. A total of 181 tumours were proved histopathologically after surgery. Enhancement pattern and regional pancreatic perfusion characteristics were analyzed. Clinical features, tumour size and pathological grading were investigated.


The frequency of isoattenuating tumours was 24.9 %. Tumour size and WHO grading was not significantly different between isoattenuating and hyperattenuating tumours. Tumour-free regions had identical blood flow (BF) regardless of their location (p = 0.35). Isoattenuating tumour-harbouring regions had lower BF compared with hyperattenuating tumour-harbouring regions; both showed higher BF compared with tumour-free neighbourhood regions (all p < 0.01). For patients with isoattenuating tumours, the overall hospital stay was longer (p < 0.01).


A substantial subset of insulinomas were isoattenuating on biphasic CT. CT perfusion showed higher BF in tumour-harbouring regions compared to tumour-free regions, providing a clue for tumour regionalization.

Key Points

About a quarter of all insulinomas were isoattenuating on biphasic contrast-enhanced CT.

CT perfusion finds tumour-harbouring regions have higher blood-flow compared to tumour-free regions.

CT perfusion provides important information for tumour regionalization, for isoattenuating tumours.


Insulinoma Multidetector computed tomography Perfusion Sporadic Multiple endocrine neoplasia 



Computed tomography


Magnetic resonance imaging


Endoscopic ultrasound


Positron emission tomography



The scientific guarantor of this publication is Professor Zheng-yu Jin. The authors of this manuscript declare no relationships with any companies, whose products or services may be related to the subject matter of the article. This study has received funding by the National Natural Science Foundation of China (General Program, No. 81371608). No complex statistical methods were necessary for this paper. Institutional Review Board approval was obtained. Written informed consent was waived by the Institutional Review Board. None of the study subjects or cohorts have been previously reported. Methodology: retrospective, observational, performed at one institution.


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Copyright information

© European Society of Radiology 2016

Authors and Affiliations

  • Liang Zhu
    • 1
  • Hua-dan Xue
    • 1
  • Hao Sun
    • 1
  • Xuan Wang
    • 1
  • Yong-lan He
    • 1
  • Zheng-yu Jin
    • 1
  • Yu-pei Zhao
    • 2
  1. 1.Department of RadiologyPeking Union Medical College HospitalBeijingChina
  2. 2.Department of General SurgeryPeking Union Medical College HospitalBeijingChina

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