Ferumoxide-enhanced magnetic resonance imaging techniques in pre-operative assessment for colorectal liver metastases

Aim: The objective was to evaluate whether contrast-enhanced magnetic resonance imaging (MRI) techniques used in a pre-operative assessment protocol for colorectal liver metastases are as accurate as spiral computer tomography during arterial portography (CTAP). Pre-operative accuracy and clinical consequences of MRI are described and compared with CTAP. Moreover, post-operative survival rate and tumour recurrence were studied.Methods: The study group comprised 84 patients which were possible candidates for a partial hepatectomy for colorectal liver metastases. Patients were pre-operatively evaluated by CT of the abdomen, CT of the thorax and spiral CTAP and ferumoxide-enhanced MRI was performed in routine way for all patients. Following this selection, 35 patients underwent a partial hepatectomy with curative intent. All patients were retrospectively evaluated.Results: Ferumoxide-enhanced MRI proved to be at least as accurate as spiral CTAP in 81% of patients. In nine patients (11%) spiral CTAP revealed more intrahepatic lesions than MRI; in only two patients (2%) did these foundings influenced the clinical decision. These patients were considered to have irresectable disease. In seven patients (8%) MRI detected more lesions than spiral CTAP and influenced the clinical decision in three patients (4%) and these did not undergo a laparotomy. The actuarial 3 year overall survival of operated patients was 41% and the actuarial 3 year disease-free survival was 19%.Conclusion: Evaluation of the clinical impact of a pre-operative assessment protocol extended with ferumoxide MRI techniques demonstrated that this non-invasive MRI technique is safe and at least as accurate as spiral CTAP. This MRI technique results in comparable clinical decisions and outcome after hepatectomy. We suggest that the performance of routine contrast-enhanced MRI should instead be used in the pre-operative evaluation of colorectal liver metastases. (C) 2002 Published by Elsevier Science Ltd.