Radiotherapy is one of the available curative
therapies for
hepatocellular carcinoma (HCC). We investigate the use of contrast-enhanced ultrasound using
Sonazoid (SCEUS) in evaluating the efficacy of
radiotherapy for HCC. We enrolled 59 patients with 59 HCCs in this retrospective study.
Tumor size and
tumor vascularity were evaluated using SCEUS before and 1, 3, 7, 10, and 13 months after
radiotherapy. The median follow-up period was 44.5 months (range: 16-82 months). Of the HCCs, 95% (56/59) had no local recurrence, while 5% (3/59) did. At 13 months after
radiotherapy, in cases with no local recurrence, SCEUS showed a reduction in
tumor vascularity in all cases, while
tumor size reduction (>30% reduction, compared with pre-
radiotherapy) was observed in 82.1% (46/56). In all three cases of local recurrence, vascularity and
tumor size reduction were not observed during the follow-up period and residual HCCs were demonstrated pathologically. Compared with cases with local recurrence,
tumor size reduction and reduction in
tumor vascularity (p < 0.001) were significantly greater in cases with no local recurrence at 13 months after
radiotherapy. SCEUS may be useful in evaluating
radiotherapy efficacy for HCC.