Dual-phase contrast enhancement multi-slice CT in grading pancreatic neuroendocrine tumors
10.3760/cma.j.issn.1005-1201.2013.03.007
- VernacularTitle:胰腺神经内分泌肿瘤多层螺旋CT双期增强扫描特征
- Author:
Yan ZHOU
;
Jianyu LIU
;
Xiang ZHU
- Publication Type:Journal Article
- Keywords:
Pancreatic neoplasms;
Tomography,X-ray computed
- From:
Chinese Journal of Radiology
2013;(3):225-230
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate characteristic clinical and imaging findings of pancreatic neuroendocrine tumors (NET) in dual-phase contrast enhancement MSCT.Methods The dual-phase contrast enhancement MSCT images of 23 lesions in 20 patients with histologically confirmed pancreatic NET were studied retrospectively.Their clinical presentations,imaging characters as well as the intensities of lesions and normal pancreas in each phase were measured,and the following indices were calculated.First,the absolute enhancement of lesions,including the increasing of CT value of the maximum enhancement area within a tumor in arterial phase,that was named A1 in short,and that of the minimum enhancement area was labeled as A2.The same ROI measured increasing CT values in portal venous phase was labeled as V1 and V2 respectively.Secondly,the relatively enhancement indices comparing with the normal pancreas in the same patient within the same phase were calculated.This included the differences between the maximum,as well as the minimum,enhancement areas of tumors and the normal pancreas in arterial phase,which was named as AP1 and AP2 respectively,and those differences in portal venous phase,which were labeled as VP1 and VP2 respectively.All of the tumors were graded as G1 to G3 according to the WHO classification in 2010.A Kruskal Wallis test were performed to compare differences of tumor diameters and the enhancement indices.The change trend of enhancement indices varying with pathology grading were described.Fisher exact test was used to find differences of clinical and imaging characters.Results Twenty-three lesions in 20 patients included 13 lesions in grade 1 (G1),8 in G2,and 2 in G3.Among the 10 patients with G1 NET,7 of them had no endocrine symptoms,while the other 3 had endocrine symptoms.Six of them had no abdominal pain,while 4 of them complained of it.All of the 10 patients with G1 NET had no hepatic metastasis.Among 8 patients with G2 NET,4 of them were with endocrine abnormality,and the other 4 were not.Five of them complained of abdominal pain while the other 3 did not.Six of them had no hepatic metastasis,and 2 of them had.Both of the 2 patients with NET in G3 did not have any endocrine abnormality,and one of them complained abdominal pain.Both of them were with hepatic metastasis.There was no difference between groups that whether or not endocrine syndrome and abdominal pain was presented (x2 =2.238,0.713,P =0.318,1.000),while hepatic metastasis was of significant differences (x2 =9.516,P =0.003).Tumor location,distinct outline,necrosis and/or calcification were not significantly different.Tumor enhancement showed a probable trend of decrease in group of higher grade.A1 decreased from (126.4 ± 45.7)HU to (38.7± 8.5)HU (x2 =7.254,P=0.027),A2 decreased from (94.1 ±31.1)HU to (22.8 ± 14.0) HU (x2 =7.323,P =0.026) and AP1 dropped from 80.6 HU(-21.8 — 169.7 HU) to -36.7 HU(-41.6—-31.7 HU) (x2 =6.778,P =0.034).All of the indices mentioned above were of significant difference and the other indices showed no significant difference (P ＞ 0.05).Conclusions Quantitative assessment of their enhancement patterns may provide useful information to preoperative grading of pancreatic NET,and tumors in a higher grade may show poorer enhancement.
