Management of vascular lake phenomenon on angiography during chemoembolization with superabsorbent polymer microspheres

Contrast material pooling on angiography within a tumor bed during embolization for hepatocellular carcinoma (HCC) presents as the vascular lake (VL) phenomenon. This retrospective study aimed to evaluate the frequency and management of VLs during chemoembolization with drug-eluting beads (DEBs) and the relationship between the VL and local response. A total of 123 HCC patients without vascular invasion or intrahepatic metastases who underwent chemoembolization with DEBs (50-100 A mu m superabsorbent polymer microspheres loaded with epirubicin) were enrolled. Gelatin sponge particles (GS) were injected for additional embolization in limited patients with steadily increasing size of VLs during DEB injection. Overall, 338 nodules were divided into three groups: lesions without a VL (non-VL; n = 250); lesions with a VL but without additional GS embolization [VL-GS (-), n = 58]; and lesions with both VL and additional GS embolization [VL-GS (+); n = 30]. The local responses were statistically compared by Fisher's exact test with the Bonferroni correction. The frequency of VLs was 26.0 % (88/338). The response rate in the non-VL group (54.0 %) was significantly lower than those in the VL-GS (-) (91.4 %; P < 0.0001) and VL-GS (+) (96.7 %; P < 0.0001) groups. VL is a common angiographic finding and might be associated with the local response.