Simplified dual time point FDG-PET/computed tomography for determining dignity of pancreatic lesions

Abstract

Background Predicting the dignity of pancreatic lesions is still a diagnostic challenge. The differentiation between benign changes in chronic pancreatitis from pancreatic cancer remains difficult. Therefore, the aim of this study was to evaluate whether early dual time point kinetics of pancreatic lesions in 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) may be helpful to differentiate pancreatic lesions. Methods We prospectively analyzed 64 patients (pancreatic cancer n = 45 and chronic pancreatitis n = 19) scheduled for dual time point FDG-PET/computed tomography scan for pancreatic lesions from 2005 to 2014. Studies were performed 60 and 90 minutes after application of 18F-FDG. Histological samples were collected for all patients, either by resection or by biopsy. Semiquantitative analysis was performed using the minimum, the maximum, and the average standardized uptake value (SUV) from the two different sets of images. To increase sensitivity and specificity, a formula addressing the weighting of standardized uptake values was created. Results With a sensitivity of 82.6%, specificity of 77.8%, accuracy of 79.7%, positive predictive value of 90.5%, and negative predictive value of 63.6% SUVmax@time1 > 3.45 was the most reliable single quantitative parameter for malignancy of the pancreatic lesions. Weighting of standardized uptake values produced a formula that showed an even better profile. Conclusions In patients with suspicious pancreatic lesions, the simplified dual time point FDG-PET/computed tomography may represent a valuable diagnostic tool in characterizing pancreatic lesions.

Is Delayed Image of 18F-FDG PET/CT Necessary for Mediastinal Lymph Node Staging in Non–Small Cell Lung Cancer Patients?

“…32 Several previous studies reported controversial and conflicting results of DTP 18 F-FDG PET/CT in various cancer type for differentiation of malignant from benign lesions. [8][9][10][33][34][35][36][37][38] In HCC patients, Oksuzoglu et al 33 showed that a significant increase in tumor SUV in delayed images in contrast to a significant decrease in background SUVs suggests that delayed images in HCC may contribute to diagnostic performance through a potential increase in the contrast between the tumor and background. According to studies performed in breast cancer patients, Yamagishi et al 34 showed that DTP 18 F-FDG PET/CT can be a useful method for predicting relapse in patients with breast cancer.…”

“…6 Recently, to better differentiation of benign from malignant conditions, many studies have found interesting results using dual-timepoint (DTP) acquisition of 18 F-FDG PET and PET/CT for various malignant diseases. [7][8][9][10][11] Few recent studies reported that retention index (RI) or % change of maximal standardized uptake values (%ΔSUV max ) calculated from early and delayed 18 F-FDG PET/CT provide a significantly more accurate diagnosis in lung cancer than does early 18 F-FDG PET or PET/CT and chest CT and that a close correlation exists between the RI and SUV results for the primary lesion and LN metastases. 12,13 Although this newly described DTP imaging of 18 F-FDG PET seems to be an effective method for distinguishing benign from malignant lesions, fewer studies has attempted to adopt this technique for the evaluation of mediastinal LN node status in patients with NSCLC with controversial results.…”

Dynamic whole-body FDG-PET imaging for oncology studies

“…In many PET studies, standardized uptake (SUV) value of FDG at the time of FDG-PET imaging is quantitatively analyzed and displayed. In addition, SUV uptake change over time is analyzed over 30-60 min using DTPI in various oncology fields [33][34][35][36][37][38][39][40]. On the basis of the concept of differences in glucose metabolism, FDG uptake tends to increase or remain high in many malignant lesions as compared to benign lesions including infection and inflammation.…”

Prognostic value of metabolic parameters measured by pretreatment dual-time-point 18F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with intrahepatic or perihilar cholangiocarcinoma

“…Recent studies have used dual-time-point 18 F-FDG PET/CT to better diagnostic or prognostic accuracy for various malignant disease, because of the more prominent 18 F-FDG uptake in malignant conditions, whereas with less 18 F-FDG uptake in benign or non-tumorous conditions on a delayed scan [8–13] . But few studies have applied this technique for assessment of malignant potential in patients with extrahepatic bile duct cancer or biliary strictures [14–16] .…”

“…[3][4][5][6][7] Recent studies have used dual-time-point 18 F-FDG PET/CT to better diagnostic or prognostic accuracy for various malignant disease, because of the more prominent 18 F-FDG uptake in malignant conditions, whereas with less 18 F-FDG uptake in benign or non-tumorous conditions on a delayed scan. [8][9][10][11][12][13] But few studies have applied this technique for assessment of malignant potential in patients with extrahepatic bile duct cancer or biliary strictures. [14][15][16] Because dual-time-point imaging technique has been known to overcome partial volume effect and to emerge as prominent small lesion, this technique might be helpful to bile duct cancers with small and narrow structure.…”