Abstract
The purpose of this study was to examine the applicability of diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) and computed tomography (CT) in the detection of lymph node metastasis of colorectal cancer. Subjects were 62 patients with colorectal cancer who were admitted in our department between October 2008 and April 2011 and underwent preoperative DWIBS and/or CT and for whom assessment of lymph node metastasis was pathologically possible. We compared cases in which lymph node metastasis was confirmed using DWIBS and CT (LN+) to those in which lymph node metastasis confirmed pathologically (n+). Sensitivity (Sens), Specificity (Spec), positive predictive value (PPV), and negative predictive value (NPV) were calculated for each case. Preoperative diagnostic performance for LN was 63%, 97%, 91%, and 82% with DWIBS and 55%, 98%, 92%, and 82% with CT for Sens, Spec, PPV, and NPV, respectively. These results were satisfactory and consistent with those obtained using fluorodeoxyglucose-position emission tomography screenings performed at other institutions. In addition to the accumulation of cases due to an increased number of institutions that are implementing DWIBS, we anticipate even further improvements in diagnostic performance owing to the development of contrast agents, imaging equipment, and progress in image processing techniques.
