Diagnostic value of ^99mTc-labeled red blood cell SPET for a solitary solid liver mass in HBV carrier patients with different echogenicities

Background/Aims: The purpose of this study is to evaluate the efficacy of technetium-99m labeled red blood cell liver single photon emission computed tomography (RBC liver SPET) in evaluating the diagnostic ability for differentiating the nature of a solitary liver tumor detected with ultrasonography in hepatitis B carrier patients. Methodology: One hundred and one hepatitis B carrier patients (56 males, 45 females, aged 13-70 years) with a solitary solid liver mass found on ultrasonography were included in this study. The final diagnosis was made after liver biopsy, aspiration with cytology and/or autopsy in 27 patients and after follow-up with both clinical and ultrasonography findings in 74 patients. Results: Hemangioma was found in 79 patients, hepatocellular carcinoma in 14, focal nodular hyperplasia in 5, fatty liver in 2, and metastasis in 1. The diagnostic sensitivity of RBC liver SPET for hemangioma, with a hyperechoic, hypoechoic, or isoechoic ultrasonography pattern, was between 75-80%, while the specificity for all patterns was 100%. For mixed-echoic lesions, the sensitivity was 100%, but the specificity was only 50%. Two false-positives were noted; both were mixed-echoic lesions. Conclusions: RBC liver SPET is useful for differentiating hemangioma from other liver tumors in hepatitis B carrier patients with a various sonographic patterns, especially for those who had a mixed-echoic sonographic liver mass.