Diffusion-derived "Vessel Density" (DDVD) and Slow Diffusion Coefficient (SDC) Signal Features of Mass-forming Intrahepatic Cholangiocarcinoma Compared to Those of Hepatocellular Carcinoma and Liver Metastases: Preliminary Results.

PURPOSE: Two new contrast types for diffusion weighted imaging (DWI) have recently been proposed: diffusion-derived "vessel density" (DDVD) and slow diffusion coefficient (SDC). DDVD reflects tissue perfusion while SDC reflects slow tissue diffusion. This study evaluates the DDVD and SDC signal features of mass-forming intrahepatic cholangiocarcinoma (ICC).

MATERIALS AND METHODS: Liver DWI data were prospectively collected. The DDVD weighted image was calculated from b=0 and b=10 s/mm2 images, and the SDC weighted image was derived with b=500 and b=800 s/mm2 images, or with b=600 and b=800 s/mm2 images or with b=400 and b=600 s/mm2 images. A semi-quantitative (SQ) scoring was conducted on DDVD map and SDC map. A liver mass lesion signal was divided into six SQ score categories: low signal (score: 0), iso-signal (score: 1), slightly high signal (score: 1.5), high signal (score: 2), higher signal (score: 2.5), and markedly high signal (score: 3). The "higher signal" was a signal notably higher than the spleen signal but lower than the liquid signal and possibly close to the kidney signal; the "markedly high signal" was close to the liquid or blood vessel signal. This study included a total of 27 patients with mass-forming ICC, 76 patients with hepatocellular carcinoma (HCC), and 30 patients with liver metastasis (Mets).

RESULTS: 86.4% of ICC lesions had a DDVD score of 0, 1 or 1.5, and 70.4% had an SDC score ≥ 2.5. 60.9% of Mets lesions had a DDVD score ≥ 2.0, and 58.6% had an SDC score ≥ 2.5. If we use "(SDC ≥ 2.5) and (DDVD of 0, or 1.0 or 1.5)" to define ICC, then it had an odds ratio of 34.7 in favor of ICC over HCC, an odds ratio of 14.4 in favor of ICC over Mets. If we use "(SDC ≥ 2.5) and (DDVD of 2.0 or 2.5)" to define Mets, then it had an odds ratio of 6.1 in favor of Mets over HCC.

CONCLUSION: When a solid liver mass has an SDC score ≥ 2.5, the possibility of its being a mass-forming ICC or Mets should be considered. If the lesion also has an iso-signal or only slightly signal on the DDVD map, then this lesion is likely to be an ICC. If the lesion also has an SQ score ≥ 2 on the DDVD, then this lesion has the possibility of being Mets.

KEY POINTS: · ICC typically shows iso-signal or only slightly signal on DDVD map and notably higher SDC signal than that of spleen.. · High DDVD signal (SQ score ≥ 2.0) and higher SDC signal (SQ score ≥ 2.5) suggest the possibility of liver metastasis.. · Integration of DDVD and SDC into practice can contribute to liver mass lesion classification..

CITATION FORMAT: · Wáng XYJ, Zheng CJ, Xu XY, et al. Diffusion-derived "Vessel Density" (DDVD) and Slow Diffusion Coefficient (SDC) Signal Features of Mass-forming Intrahepatic Cholangiocarcinoma Compared to Those of Hepatocellular Carcinoma and Liver Metastases: Preliminary Results. Rofo 2026; DOI 10.1055/a-2830-5742.