Utilization of relative evaluation of pancreatic perfusion CT parameters to support appropriate pancreatic...

To investigate the effect of relative evaluation of perfusion computed tomography (PCT) parameters in the diagnosis of pancreatic adenocarcinoma (PAC).

Of the 117 patients in which PCT was performed (May 2019 to June 2023), 99 patients with mass lesions (MLs), including 50 PAC and 11 patients with mass-forming pancreatitis (MFP), and 15 patients without MLs but with main pancreatic duct (MPD) abnormalities, including 6 PAC and 7 no diagnosis of malignancy (NDM) cases were enrolled in this study. Parameter values were obtained from parametric maps of blood flow (BF), blood volume (BV), and mean transit time (MTT) for the ML and abnormal MPD part (AMP), pancreas and spleen. Diagnostic performance was evaluated based on receiver operating characteristic analysis for absolute values and relative values for pancreas and spleen.

BF_ML, BV_ML, BF_ML/Pancreas, BF_ML/Spleen, BV_ML/Pancreas and BV_ML/Spleen were significantly lower in PAC than MFP cases. Areas under the curve (AUCs) for BF_ML, BF_ML/Pancreas, BF_ML/Spleen were 0.71 (sensitivity, 54 %; specificity, 91 %), 0.80 (sensitivity, 74 %; specificity, 82 %) and 0.79 (sensitivity, 68 %; specificity. 91 %), respectively. The AUCs for BV_ML, BV_ML/Pancreas, BV_ML/Spleen were 0.72 (sensitivity, 48 %; specificity, 100 %), 0.85 (sensitivity, 76 %; specificity, 91 %) and 0.87 (sensitivity, 76 %; specificity, 91 %), respectively, with significantly better diagnostic performance on relative evaluation (P < 0.05). BV_AMP/Spleen and MTT_AMP/Spleen were significantly higher in PAC than NDM cases, with AUCs of 1 (100 % sensitivity and specificity) and 0.91 (sensitivity, 86 %; specificity, 100 %), respectively.

Relative evaluation of PCT parameters is expected to contribute to more appropriate diagnosis of PAC.