Résumé
Hepatocellular carcinoma in cirrhosis is a multistage process that includes large regenerative nodules, dysplastic nodules, and hepatocarcinoma. The aim of this study was to establish whether contrast-enhanced Doppler ultrasonography [US] is able to distinguish between early hepatocellular carcinoma [HCC] and small nonmalignant nodules in cirrhosis. Between January 2002 and December 2002, 250 cirrhotic patients with no previous history of HCC or evidence of hepatic focal lesions were enrolled and prospectively followed-up with US every 6 months until December 2002. Thirty patients developed focal lesions, 6 multifocal, and 24 monofocal. Biopsy of focal lesions, contrast enhanced Doppler US and spiral computed tomography [CT] were performed in 21 patients with small [<3 cm] monofocal lesions. Ten nodules were diagnosed as HCC and II as nonmalignant [8 large regenerative nodules, 1 low-grade, and 2 high-grade dysplastic nodules] by liver biopsy. Iritratumoral arterial blood flow was detected in 9 of 10 [90%] HCC and 3 of 11 [27%] nonmalignant nodules by contrast-enhanced Doppler US [P<.0001]. The mean peak resistance and pulsatility indices were 0.82+0.09 and 1.56+0.2 in HCC and 0.62+0.08 and 0.82+0.08 in dysplastic lesions [P=.002 and .0001], respectively. Spiral CT revealed arterial perfusion in 9 of 10 HCC and in 2 of 11 nonmalignant nodules [high-grade dysplastic nodules]. Two of the apparently false-positive nodules at enhanced Doppler VS were high-grade dysplastic nodules and evolved to HCC during follow-up. In conclusion, contrast-enhanced Doppler US is a noninvasive, very sensitive technique in differentiating malignant and premalignant lesions from nonmalignant focal lesions in the liver