Usefulness of contrast-enhanced ultrasonography with a new contrast mode, Agent Detection Imaging, in evaluating therapeutic response in hepatocellular carcinoma treated with radio-frequency ablation therapy.
Objective: The therapeutic response of radio-frequency ablation (RFA) for hepatocellular carcinoma (HCC) was evaluated by contrast-enhanced ultrasonography (US) using a new contrast mode, agent detection imaging (ADI), and its usefulness was compared with that of dynamic computed tomography (CT). Materials and methods: Forty patients with 64 nodules diagnosed as HCC histologically and/or by various imaging modalities were evaluated with ADI (1 and 7 days after treatment) and Dynamic CT (7 days after treatment). Results: ADI and dynamic CT revealed residual lesions in 15 and 12 nodules, and no residual lesions in 45 and 52 nodules, respectively. ADI yielded indeterminate findings in four nodules; although the vascular phase showed minute residual tumor vessels, the tumor appeared to be completely contained within the ablated area in the delayed phase. In these indeterminate cases, US-guided biopsies of the areas of residual vascularity revealed no viable cancer cells; only degenerated tissues. Conclusion: In assessing the therapeutic response of RFA for HCC, ADI has a similar competence to dynamic CT. Even if the vascular phase of contrast-enhanced US shows minute residual vessels, as long as the tumor is safely contained within the ablated area in the delayed phase, the cancer cells are likely to be degenerated.
Fourth Department of Internal Medicine, Tokyo Medical University, 6-7-1 Nishishinjuku Shinjuku-ku, Tokyo 160-0023, Japan.
Masafumi
M
Shimizu
Hiroko
H
Iijima
Toshiya
T
Horibe
Masahiko
M
Yamada
Shiro
S
Suzuki
Kyosuke
K
Yanagisawa
Tomoyuki
T
Seki
Fuminori
F
Moriyasu