Improved Detection of Hepatic Metastases From Pancreatic Cancer Using Periodically Rotated Overlapping Parallel Lines With Enhanced Reconstruction (PROPELLER) Technique After SPIO Administration

Abstract

The purpose of this study was to evaluate the detection of hepatic metastases from the pancreatic cancer using different MR imaging methods, including superparamagnetic iron oxide (SPIO)-enhanced fat-saturated T2-weighted imaging with periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) technique. The institutional review board approved this prospective study. Eighty-two patients (mean age, 55 years) underwent different MR imaging with a 1.5-T scanner. Diagnostic performance with receiver operating characteristics (ROC) curves and sensitivity were evaluated for the following image sets: (A) unenhanced images (T1-weighted in-phase and opposed-phase gradient-echo [GRE] images, and fat-saturated T2-weighted turbo spin-echo [TSE] images) that were included in the subsequent image sets, (B) diffusion-weighted images, (C) SPIO-enhanced fat-saturated T2-weighted TSE images with prospective acquisition correction (PACE), (D) SPIO-enhanced T2*-weighted GRE images, and (E) SPIO-enhanced fat-saturated T2-weighted TSE images acquired with PROPELLER and PACE. The areas under the ROC curves were 0.58 +/- 0.05 (mean +/- standard errors), 0.81 +/- 0.04, 0.70 +/- 0.05, 0.80 +/- 0.04, and 0.90 +/- 0.03, and sensitivity was 0.47, 0.69, 0.56, 0.66, and 0.77 for image sets (A) to (E), respectively, for all lesions. Image set (E) had significantly larger area under the ROC curve for detection of hepatic lesions and higher sensitivity than others. SPIO-enhanced fat-saturated T2-weighted MR imaging with the PROPELLER technique is more effective for detecting hepatic metastases of pancreatic cancer than diffusion-weighted MR imaging, SPIO-enhanced fat-saturated T2WI without the PROPELLER technique, or SPIO-enhanced T2*-weighted GRE imaging.