Gadoxetic acid-enhanced magnetic resonance imaging (MRI) exhibits the ability to predict which patients with liver cancer may have a poor prognosis, according to a study published in Medicine. Such information can aid in treatment planning for hepatocellular carcinoma (HCC) and also help identify which patients should be closely monitored for signs of early recurrence after treatment.
Poorly differentiated HCC is associated with a poor prognosis. Liver biopsy before treatment can often determine differentiation degrees, but it is an invasive procedure. MRI images acquired with the use of a gadolinium-ethoxybenzyl-diatylentriamine (Gd-EOB-DTPA) contrast agent can allow liver function to be quantitatively assessed. Because HCC cells cannot uptake gadoxetic acid contrast agenty, they display as hypointense nodules on the hepatobiliary phase of gadoxetic acid enhanced MR image.
Researchers from the Inha University School of Medicine in Incheon, South Korea conducted a retrospective study to assess the relationship between the grade of HCC enhancement and histologic grade. Their objective was also to identify factors predictive of the presence of poorly differentiated HCC.
The study group consisted of 121 patients with HCC who had undergone a gadoxetic acid-enhanced MRI following a dynamic CT scan prior to treatment. The research team recorded tumor type, the number of tumors and sizes, and the presence or absence of vascular invasion. Signal intensities of HCC and peri-HCC areas were measured using regions of interest. The team calculated relative intensity ratios of HCC lesions on unenhanced images and on hepatobiliary phase images, as well as relative liver enhancement (RLE) ratios.
After calculating the histologically grade HSS for each tumor with the Edmondson-Steiner (E-S) grading system, these were compared the mean RLE for each patient. Lead author Young-Joo Jin, MD, PhD, of the Department of Internal Medicine and colleagues reported that the mean RLE of E-S grade IV (indicative of poorly differentiated HCC) was significantly lower than that of patients with E-S grades I-III. Mean RLE also was significantly different for each E-S grade.
Mean RLE was found to predict E-S grade IV significantly in HCC patients. Although the enhancement degree of liver on the hepatobiliary phase of the imaging can be influenced by the severity of patients with liver cirrhosis, the authors reported that for their study, the presence of cirrhosis did not have a confounding effect.
“Poorly differentiated HCC may be preoperatively distinguished from well or moderately differentiated HCCs,” the authors wrote. Noting that preoperative gadoxetic acid enhanced MRI examinations are often ordered for liver cancer patients to reduce the risk of missing HCC lesions, their study findings may provide a basis for the routine addition of this examination in HCC patients schedule for surgical resection. They recommended that additional research be conducted to confirm their findings.
Gadoxetic acid enhanced MRI identifies prognosis of liver cancer patients. Appl Radiol.