DIAGNOSIS OF LIVER METASTASES FROM COLORECTAL ADENOCARCINOMA - COMPARISON OF SPIRAL-CTAP COMBINED WITH INTRAVENOUS CONTRAST-ENHANCED SPIRAL-CT AND SPIO-ENHANCED MR COMBINED WITH PLAIN MR-IMAGING

Purpose: The purpose of this study was to determine whether MR with an d without SPIO (AMI-25) could replace spiral-CTAP in the staging of co lorectal adenocarcinoma. Material and Methods: Thirty-five patients we re studied prospectively by means of i.v. contrast-enhanced spiral-CT, spiral-CTAP, and MR of the liver. MR imaging was performed before and after infusion of AMI-25. Diagnoses were compared to intraoperative f indings (n=35) which included intraoperative ultrasound (n=21), and fo llow-up CT (n=18). Results and Conclusion; Fifteen patients were found to have a total number of 53 liver metastases and 43 benign lesions w ere detected. Evaluation was performed in four different ways: 1) i.v. contrast-enhanced spiral-CT; 2) i.v. contrast-enhanced spiral-CT + sp iral-CTAP; 3) plain MR; 4) plain MR + SPIO-enhanced MR. I.v. contrast- enhanced spiral-CT, spiral-CTAP and SPIO-enhanced MR identified patien ts with liver metastases with equal sensitivity. However, owing to its significantly higher sensitivity, based on a lesion-by-lesion analysi s, spiral-CTAP cannot be replaced by SPIO-enhanced MR in patients who are to undergo liver resection. A limitation in spiral-CTAP is its rel atively low specificity.