Chemical Shift Effect Predicting Lymph Node Status in Rectal Cancer using High-Resolution MR Imaging with Node-for-node Matched Histopathological Validation

To evaluate the value of chemical shift effect (CSE), as well as other criteria for the prediction of lymph node status. Lymph nodes harvested from transversely whole-mount specimens were compared with in vivo and ex vivo images to obtain MR characteristics including CSE, as well as other predictors of 255 benign and 35 metastatic nodes. Our results revealed that CSE is a reliable predictor for differentiating benign from metastatic lymph nodes. Other predictors of nodal location, border, signal intensity and minimum distance to rectal wall were also proved to be useful for the diagnosis.