Power Doppler signals after percutaneous ethanol injection therapy for hepatocellular carcinoma predict local recurrence of tumors: a prospective study using 199 consecutive patients

Background/Aims: This study was prospectively conducted to elucidate the relationship between pre-/post-treatment power Doppler signals of hepatocellular carcinoma (HCC) and local recurrence. Methods: One hundred ninety-nine consecutive patients with 359 HCC lesions receiving percutaneous ethanol injection therapy (PEIT) as a first-line option were enrolled. Arterial power Doppler signals in the tumor were found in 130 nodules, but not detected in 229. After confirmation of complete tumor necrosis on dynamic CT, Doppler signals in nodules were re-evaluated. Patients received periodical examinations to detect HCC recurrence. Results: Local HCC recurrence was observed in 36 lesions; 22%(28/130) of the pretreatment signal positive lesions, in contrast to 3.5%(8/229) of the pretreatment signal negative lesions (P<0.01). Out of 130 signal positive nodules, signals disappeared in 120 (92%) after PEIT, but were present in ten (8%). During the 25-month follow up, local recurrence was detected in 19 (16%) from the former, in contrast to nine (90%) from the latter (P<0.001). Uni- and multivariate Cox analysis revealed that the presence of pre-/post-treatment power Doppler signals, histological differentiation and tumor number were independent factors for local recurrence. However, 3-year recurrence rate of new lesions was 51%, but no predictors were identified. Conclusions: Residual Doppler signals in tumor after PEIT were related to the local HCC recurrence.