| [Objective] This study retrospectively analyzed patients with pancreatic lesions. To evaluate the value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography(18F-FDG PET/CT) imaging in the differential diagnosis, staging and postoperative recurrence and distant metastasis diagnosis in pancreatic diseases, and compare with serum CA19-9, contrasted-enhanced computed tomography?CECT?, contrasted-enhanced magnetic resonance imaging?CEMR?.[Methods] Patients with highly suspected pancreatic diseases were included in this retrospective study from Jan 2011 to Dec 2014 in our center. These patients were divided into 3 groups according to different aims:1. For the preoperatively differential diagnosis:?1? the single PET/CT imaging?n=363?;?2? concurrent PET/CT imaging and serum CA19-9 inspection?n=254?;?3? concurrent PET/CT and CECT imaging?n=142?;?4? concurrent PET/CT and CEMR imaging?n=59?;?5? concurrent PET/CT, CECT and CEMR imaging?n=32?.2. For staging diagnosis:?1? PET/CT, CECT and CEMR imaging: the single PET/CT imaging?n=40?, concurrent CECT and PET/CT imaging?n=25?,concurrent CEMR and PET/CT imaging?n=13?;?2? PET/CT, CECT and CEMR imaging for the diagnosis of hepatic metastases: single PET/CT imaging?n=210?, concurrent CECT and PET/CT imaging?n=88?, concurrent CEMR and PET/CT imaging?n=27?.3. Postoperatively recurrence and distant metastasis diagnosis:?1? single PET/CT imaging?n=51?;?2? concurrent PET/CT imaging and serum CA19-9 inspection?n=33?;?3? concurrent CECT and PET/CT imaging?n=22?.The final golden-standard diagnosis was the pathological diagnosis after surgery or long-term clinical follow-up over 6 months. PET/CT images were reviewed visually and obtained semi-quantitative value SUVmax?the maximum standard uptake value? by two experienced senior physicians of nuclear medicine. Similarly, the CECT and CEMR scans were retrospectively evaluated in consensus by two experienced senior radiologists. The normal value of CA19-9 was ranging from 2 to 37 U/m L. The level of serum CA19-9 and SUVmax were recorded. The sensitivity, specificity and accuracy of PET/CT, serum CA19-9, CECT, CEMR and combined detection were calculated. Using T test in measurement data, ROC curves for optimal cutoff value, X2 test or Cochran's Q test in count date and Kappa test in the consistency with the golden standard, and P<0.05 was considered statistically significant.[Results] Totally 363 consecutive patients with highly suspected pancreatic diseases were included in this study, with 226 male and 137 female. The mean age was 58.58±12.12 y?range from 21 to 95 y?. The final diagnoses of these patients were 210 with malignant lesions and the other 153 with benign diseases, in which 79 malignant and 31 benign lesions were confirmed by pathology.1.For the preoperative differential diagnosis:?1? The subgroup of single PET/CT imaging: the total sensitivity, specificity and accuracy value were 92.4%, 96.7%, and 94.2%, respectively, with an excellent consistency with the golden standard?n=363, k=0.88, P=0.000?. SUVmax were 7.49±4.20?n=210? and 2.72±2.40?n=153? in malignant and benign lesions, respectively, which showed significant difference?t=13.97, P=0.000?. When the cut-off point of SUVmax was 3.75 obtained from the ROC curve, the area under the curve?AUC? was 0.916 with the highest sensitivity?92.4%? and specificity?81.7%?. These suggested that SUVmax may be helpful in the differential diagnosis of the benign and malignant pancreatic lesions.?2? The subgroup of concurrent PET/CT imaging and serum CA19-9 inspection: CA19-9 were 645.09±527.78U/m L, 100.73±240.94U/m L for the 149 consecutive malignant and 105consecutive benign lesions respectively, which had statistical difference?t=11.81, P=0.000?. The sensitivity, specificity, accuracy and kappa value of concurrent CA19-9, PET/CT and combined inspections were 81.21%, 90.60%, 96.64%; 60.00%, 95.24%, 56.19%; 72.4%, 92.52%, 79.92%; 0.42, 0.85, 0.56?n=254?, respectively. In ROC analysis, the AUC of CA19-9 and SUVmax were 0.815 and 0.901, respectively. Moreover, the cut-off of CA19-9 in ROC was 105.35 U/m L, with sensitivity 73.15% and specificity 84.76%.?3? The subgroup of concurrent CECT and PET/CT imaging: the sensitivity, specificity, accuracy and kappa value of concurrent CECT, PET/CT and combined imaging were 81.82%, 87.50%, 94.32%; 75.93%, 100.00%, 75.93%; 79.58%, 92.25%, 87.32%; 0.57, 0.72, 0.84?n=142?, in which 88 with malignant lesions and the other 54 with benign diseases, respectively. Moreover, CECT and combined inspections had shown significant difference in specificity?p=0.001?.?4?The subgroup of concurrent CEMR and PET/CT imaging: the sensitivity, specificity, accuracy and kappa value of concurrent CEMR, PET/CT and combined imaging were 88.89%, 92.59%, 92.59%; 65.63%, 93.75%, 65.63%; 76.27%, 93.22%, 77.92%; 0.53, 0.86, 0.57?n=59?, in which 27 with malignant lesions and the other 32 with benign diseases, respectively. Furthermore, the difference between PET/CT and CEMR, PET/CT and combined inspections in specificity showed statistical significance.?5? The subgroup of concurrent CECT, CEMR and PET/CT imaging: the sensitivity, specificity and accuracy value of concurrent CECT, CEMR, PET/CT and combined imaging were 85.71%, 100%, 100%, 100%; 88.89%, 77.78%, 100%, 94.44%; 87.50%, 87.50%, 100.00%, 96.88%?n=32?, in which 14 with malignant lesions and the other 18 with benign diseases, respectively. However, there was not statistical difference between them.2. For staging diagnosis:?1?The subgroup of PET/CT, CECT and CEMR imaging: This subgroup study included 40 cases of PET/CT, 25 of CECT and 13 of CECT imaging. On the T, N, M and pathologicalstage, the accuracy of PET/CT, CECT, CEMR were 62.86%?22/35?, 47.83%?11/23?, 46.15%?6/13?; 65.71%?23/35?, 62.50%?15/24?, 46.15%?6/13?; 94.87%?37/39?, 75.00%?18/24?, 60.00%?9/13?; 62.50%?25/40?, 24.00%?6/25?,23.08%?3/15?, respectively. In addition, concurrent PET/CT imaging which properly adjusted clinical management of 8.70%?2/23? patients based on CECT and 30.77%?4/13? for CEMR.?2? The subgroup of pancreatic cancer in hepatic metastases: with 142 patients detected distant metastases as staging ? by pathology or concurrent imaging?n=210?, in which were 83 cases of hepatic metastases.?1?the sensitivity, specificity, accuracy value of single PET/CT imaging were 90.36%, 99.21%, 95.71%, with an excellent consistency with the golden standard?n=210, k=0.91, P=0.000?;?2?the sensitivity, specificity, accuracy and kappa value of concurrent PET/CT and CECT imaging were 90.00%, 83.33%; 98.27%, 98.28%; 95.45%, 94.32%; 0.90, 0.84?n=88?, respectively;?3?the sensitivity, specificity, accuracy and kappa value of concurrent PET/CT and CEMR were 55.56%, 88.89%; 94.44%, 94.44%; 81.48%, 92.59%; 0.55, 0.83, respectively. However, there were not statistical differences between them in sensitivity?p=0.25?.3. For the diagnosis of postoperative recurrence and distant metastasis:?1?Totally 51 consecutive postoperative patients were included in this study, with 31 male and 20 female. The mean age was 54.10±10.17y?range from 21 to 95 y?. The final diagnosis of these patients were 37 with recurrence and the other 14 with non-significant progress, in which 3 recurrence and 2 non-significant progress patients were confirmed by pathology.?2?In the subgroup of single PET/CT imaging: the total sensitivity, specificity and accuracy of postoperative PET/CT imaging were 97.30%?36/37?, 92.86%?13/14? and 96.08%?49/51?, respectively. Although there were one out of thirty-seven consecutive false negative and one out of fourteen consecutive false positive, PET/CT imaging existed an excellent consistency with the golden standard in postoperative patients?k=0.90, P=0.000?.?3?In the subgroup of concurrent serum CA19-9, PET/CT imaging and combined inspections: the sensitivity, specificity, accuracy and kappa value were 78.57%, 96.43%, 100%; 60.00%, 80.00%, 40.00%; 75.76%, 93.94%, 90.91%; 0.29, 0.76, 0.53?n=33?, respectively. 0.832 as AUC were, the cut-off of serum CA19-9 in ROC was 158.35U/m L, with sensitivity 64.28% and specificity 100%.?4?In the subgroup of concurrent CECT, PET/CT and combined imaging: 18 consecutive relapse and 4 consecutive non-significant progress included, the sensitivity, specificity, accuracy and kappa value of CECT, PET/CT and combined detection were 72.22%, 94.44%, 94.44%; 25.00%, 75.00%, 25.00%; 63.64%, 90.91%, 81.82%;-0.23; 0.70; 0.24?n=22?, respectively. Nevertheless, these differences of sensitive and specificity were not statistically significant.[Conclusions] Firstly, in the differential diagnosis of benign and malignant pancreatic lesions, the staging of pancreatic cancer, as well as postoperative recurrence and distant metastasis, 18F-FDG PET/CT had important clinical value, and was higher and partial statistically higher than concurrent CECT, CEMR imaging and serum CA19-9 inspection, except that was nonstatistically lower than CEMR imaging in the diagnosis of hepatic metastases. Secondly, serum CA19-9, which critical value is 37U/m L, had limited effects on diagnosis of the preoperative discrimination, postoperative recurrence and distant metastasis in pancreatic cancer. Thirdly, as another example of the importance of integrating imaging with blood tests, PET/CT combined with CECT, CEMR or serum CA19-9 can improve the screening of pancreatic cancer and postoperative recurrence or metastasis. |
PDF Full Text Request