Dr. Zahra Kassam, MD

Abbreviated MRI

for Colon Cancer with Liver Metastasis

After a patient is diagnosed with colon cancer, they receive a CT of the chest, abdomen, and pelvis to see if the cancer has spread (metastasized) to other parts of the body. A common site for the cancer to spread to is the liver. If an abnormality is seen in the liver on CT, sometimes an MRI of the liver is required to determine a) whether it is cancer or not and b) whether there are small tumours in the liver that were not visible on CT. During the MRI, the patient is injected with intravenous (IV) contrast. This makes liver lesions more conspicuous and also helps determine if they are cancerous or not. The most commonly used IV contrast agent is called Gadovist. However, there is another IV contrast agent called Primovist that is better at detecting liver metastases from colon cancer than Gadovist. This is very important information for surgeons, because if they considering cutting out (resecting) the liver tumours, they want to make sure they get them all. Unfortunately, Primovist is used sparingly in Canadian hospitals because it is more expensive than Gadovist and the MRI takes longer. Some early small studies have suggested that it may be possible to shorten the Primovist MRI significantly (e.g. from 60 minutes to 15 minutes), making it economically feasible to offer Primovist to more patients. However, there have not been any large studies performed to confirm these findings. The purpose of this study is to compare the accuracy of colon cancer liver metastasis detection between a regular, full-length Primovist MRI versus a shortened Primovist MRI protocol. The economic impact will also be assessed.