Report from SIR: fMRI predicts response to treatment for liver cancer

March 21, 2008

Contrast enhancement and metabolic changes detected with functional MR imaging can be used to anticipate the effects of transarterial chemoembolization on primary and metastatic tumors of the liver.

Contrast enhancement and metabolic changes detected with functional MR imaging can be used to anticipate the effects of transarterial chemoembolization on primary and metastatic tumors of the liver.

Clinical trials from Johns Hopkins University and Northwestern University come on the heels of a third study showing that contrast-enhanced and diffusion-weighted MRI can confirm the effects of transarterial chemoembolization (TACE) on liver metastases from neuroendocrine tumors. The data were presented March 17 at the Society of Interventional Radiology meeting in Washington, DC.

Hepatocellular carcinoma is the third leading cause of cancer deaths worldwide and merits consideration as a chronic disease in the developed world, according to researchers.

Functional imaging has been proven useful to characterize lesions in the liver, but no study to date had looked at the possibility of predicting response to TACE, said principal investigator Neel K. Naik, a medical student at Northwestern.

Naik and colleagues enrolled 21 patients with HCC who underwent TACE and intra/postprocedural 1.5T gadolinium-enhanced T1-weighted MR and DWI with follow-up at one and three months.

MRI techniques currently available may take up to three months to detect relevant changes during the course of treatment. The investigators found DWI changes did occur a few weeks after treatment began and they were useful to predict TACE effects two months before they actually took place and became evident on imaging.

In another study, interventional radiology fellow Dr. Josephina A. Vossen and colleagues at Johns Hopkins evaluated 19 patients with unresectable primary (n = 11) and metastatic (n = 8) liver tumors treated with TACE. Patients underwent unenhanced/contrast-enhanced MRI and MR spectroscopy before and after a single treatment. Two radiologists interpreted results by consensus.

They found 11 patients with successful tumor embolization showed loss of choline peak on MR spectroscopy, significant increase in apparent diffusion coefficient values (22%, p = 0.004), and significant decrease in tumor arterial and venous enhancement (43%, p = 0.005 and 40%, p = 0.002, respectively). Patients with no evidence of tumor response had a stable choline concentration, tumor enhancement, and ADC.

"These functional findings preceded tumor regression in size, and may be utilized to detect early therapeutic response," Vossen said.

For more information from the Diagnostic Imaging archives:

fMRI shows response to treatment for neuroendocrine liver metastases

Chinese interventionalists use fresh techniques to improve outcomes

Radioembolization proves its worth in hepatic cancer