Relationship between signal intensity on hepatobiliary phase of gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced MR imaging and prognosis of borderline lesions of hepatocellular carcinoma

PurposeTo elucidate the incidence of signal intensity patterns of borderline lesions of hepatocellular carcinoma (HCC) on hepatobiliary phase Gd-EOB-DTPA (EOB) enhanced MRI and clarify the natural histories of these lesions.Materials and methodsTotal 99 borderline lesions of HCC were identified by angiography-assisted CT. The signal intensity of borderline lesions on hepatobiliary phase of EOB-enhanced MRI was analyzed. Progress rate from borderline lesions to hypervascular HCC was calculated with the Kaplan-Meier method among each signal intensity groups of nodules.ResultsOn hepatobiliary phase of EOB-enhanced MRI, 41.4% of the borderline lesions showed hypo-, 42.4% showed iso-, and 16.2% showed hyperintense, compared to background liver. Overall progress rates from borderline lesions to HCC were 10% in 1-year, 14% in 2-year and 20% in 3-year follow-up period. Progress rates to HCC in hypointense borderline lesions were 17% in 1-year, 28% in 2-year and 41% in 3-year follow-up period, and in isointense borderline lesions were 7% in 1-year, 7% in 2-year and 7% in 3-year follow-up period. No hyperintense borderline lesions progressed to HCC in follow-up period.ConclusionAlthough borderline lesions of HCC may show hypo-, iso- and hyperintensity on hepatobiliary phase of EOB-enhanced MRI, hypointense borderline lesions are high risk to progress HCC.