Background: Changes in the biological behavior of residual viable hepatocellular carcinoma (HCC) tissue after transcatheter arterial chemoembolization (TACE) remain unclear. Several studies have reported that TACE inhibits tumor angiogenesis and induces tumor cell apoptosis, while other studies have found that TACE stimulates tumor angiogenesis and thus increases the proliferative activity of the tumor cells to some degree.
Purpose: To investigate the intratumoral microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression in residual surviving cancerous tissue after TACE in HCC.
Material and methods: Tumor specimens from 63 histopathologically diagnosed patients were studied: 42 comprising the control group (treated by surgery alone) and 21 comprising the TACE group (those treated by TACE 1-2 times prior to surgical resection). The number of VEGF-positive cells, MVD, and microvessel diameter were measured.
Results: The MVD was 51.69+/-18.17 and 58.57+/-15.75 in the control and TACE groups, respectively. There was no significant difference between the two groups (t=1.48, P>0.05). The microvessel diameter was 17.62+/-10.54 microm and 15.79+/-7.65 microm in the control and TACE groups, respectively, indicating no significant difference between the two groups (t=0.71, P>0.05). The number of VEGF-positive cells in the TACE group, i.e., 243.66+/-88.88, was higher than that in the control group, i.e., 138.26+/-65.24 (t=5.34, P<0.01). TACE increased VEGF expression in the residual surviving HCC tissues, and there was a positive correlation between VEGF expression and MVD (r=0.4936, t=4.4329, P<0.05) in the HCC tissue.
Conclusion: The study indicates that the residual surviving cancerous tissue in HCC after TACE has a rich vascularity. TACE increases VEGF expression in the residual surviving cancerous tissue.