Abstract
Purpose
To investigate staging accuracy of MR for pancreatic neuroendocrine neoplasms (PNETs) and imaging findings according to the tumor grade.
Materials and methods
Our study consisted of 39 patients with PNET G1 (n = 24), PNET G2 (n = 12), and pancreatic neuroendocrine carcinoma (PNEC) (n = 3). All underwent preoperative MRI. Two radiologists retrospectively reviewed MR findings including tumor margin, SI on T2WI, enhancement patterns, degenerative change, duct dilation, and ADC value. They also assessed T-stage, N-stage, and tumor size. Statistical analyses were performed using Chi square tests, ROC analysis, and Fisher’s exact test.
Results
Specific findings for PNEC or PNET G2 were ill-defined borders (P = 0.001) and hypo-SI on venous- and delayed-phase (P = 0.016). ADC value showed significant difference between PNET G1 and G2 (P = 0.007). The Az of ADC value for differentiating PNET G1 from G2 was 0.743. Sensitivity and specificity were 70% and 86%. Accuracy for T-staging was 77% (n = 30) and 85% (n = 33), and for N-staging was 92% (n = 36) and 87% (n = 34) with moderate agreement. T-stage showed significant difference according to tumor grade (P < 0.001), although there was no significant difference in tumor size or N-stage.
Conclusion
Ill-defined borders and hypo-SI on venous- and delayed-phase imaging are common findings of higher grade PNET, and ADC value is helpful for differentiating PNET G1 from G2. MR is useful for preoperative evaluation of T-, N-stage. Tumor size of PNET and T-stage showed significant difference according to tumor grade.
Similar content being viewed by others
References
Ehehalt F, Saeger HD, Schmidt CM, Grützmann R (2009) Neuroendocrine tumors of the pancreas. Oncologist 14(5):456–467
Bosman FT, Carneiro F, Hruban RH, Theise N (2010) WHO classification of tumours of the digestive system. Lyon: IARC Press
Liszka Ł, Pająk J, Mrowiec S, et al. (2011) Discrepancies between two alternative staging systems (European Neuroendocrine Tumor Society 2006 and American Joint Committee on Cancer/Union for International Cancer Control 2010) of neuroendocrine neoplasms of the pancreas. A study of 50 cases. Pathology-Research and Practice 207(4):220–224
Rindi G, Klöppel G, Alhman H, et al. (2006) TNM staging of foregut (neuro) endocrine tumors: a consensus proposal including a grading system. Virchows Arch 449(4):395–401
Rindi G, Klöppel G, Couvelard A, et al. (2007) TNM staging of midgut and hindgut (neuro) endocrine tumors: a consensus proposal including a grading system. Virchows Arch 451(4):757–762
Sellner F, Thalhammer S, Stättner S, Karner J, Klimpfinger M (2011) TNM stage and grade in predicting the prognosis of operated, non-functioning neuroendocrine carcinoma of the pancreas—a single-institution experience. J Surg Oncol 104(1):17–21
Bushnell DL, Baum RP (2011) Standard imaging techniques for neuroendocrine tumors. Endocrinol Metab Clin North Am 40(1):153
Caramella C, Dromain C, De Baere T, et al. (2010) Endocrine pancreatic tumours: which are the most useful MRI sequences? Eur Radiol 20(11):2618–2627
Herwick S, Miller FH, Keppke AL (2006) MRI of islet cell tumors of the pancreas. AJR Am J Roentgenol 187(5):W472–W480
Ku YM, Shin SS, Lee CH, Semelka RC (2009) Magnetic resonance imaging of cystic and endocrine pancreatic neoplasms. Top Magn Reson Imaging 20(1):11–18
Lewis RB, Lattin GE, Paal E (2010) Pancreatic endocrine tumors: radiologic-clinicopathologic correlation. Radiographics 30(6):1445–1464
Lee SS, Byun JH, Park BJ, et al. (2008) Quantitative analysis of diffusion-weighted magnetic resonance imaging of the pancreas: usefulness in characterizing solid pancreatic masses. J Magn Reson Imaging 28(4):928–936
Wang Y, Chen ZE, Yaghmai V, et al. (2011) Diffusion-weighted MR imaging in pancreatic endocrine tumors correlated with histopathologic characteristics. J Magn Reson Imaging 33(5):1071–1079
Edge SB, Byrd DR, Compton CC, et al. (2010) AJCC cancer staging manual, 7th edn. New York: Springer, pp 285–296
Ekeblad S, Skogseid B, Dunder K, Öberg K, Eriksson B (2008) Prognostic factors and survival in 324 patients with pancreatic endocrine tumor treated at a single institution. Clin Cancer Res 14(23):7798–7803
Park HS, Lee JM, Choi HK, et al. (2009) Preoperative evaluation of pancreatic cancer: comparison of gadolinium-enhanced dynamic MRI with MR cholangiopancreatography versus MDCT. J Magn Reson Imaging 30(3):586–595
Ichikawa T, Federle M, Ohba S, et al. (2000) Atypical exocrine and endocrine pancreatic tumors (anaplastic, small cell, and giant cell types): CT and pathologic features in 14 patients. Abdom Imaging 25(4):409–419
Rha SE, Jung SE, Lee KH, et al. (2007) CT and MR imaging findings of endocrine tumor of the pancreas according to WHO classification. Eur J Radiol 62(3):371–377
Balci NC, Perman WH, Saglam S, et al. (2009) Diffusion-weighted magnetic resonance imaging of the pancreas. Top Magn Reson Imaging 20(1):43
Mottola JC, Sahni VA, Erturk SM, et al. (2012) Diffusion-weighted MRI of focal cystic pancreatic lesions at 3.0-Tesla: preliminary results. Abdom Imaging 37(1):110–117
Acknowledgments
We would like to thank Bonnie Hami, MA (USA) for her editorial assistance in the preparation of this manuscript.
Conflict of interest
No conflict of interest.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Kim, J.H., Eun, H.W., Kim, Y.J. et al. Staging accuracy of MR for pancreatic neuroendocrine tumor and imaging findings according to the tumor grade. Abdom Imaging 38, 1106–1114 (2013). https://doi.org/10.1007/s00261-013-0011-y
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00261-013-0011-y