Bonalumi U

Changes in vascularity of liver tumours after hepatic arterial embolization with degradable starch microspheres

The role of vascularity as a prognostic factor was investigated in 35 patients undergoing arterial chemotherapy for liver tumours. Compared with parenchyma, tumour vascularity was classified as hot (18 cases), cold (12 cases), and mixed (12 cases) using 99mTc-macroaggregated albumin (MAA) hepatic arterial scans. The proportion of patients showing complete and partial responses to treatment was higher in the hot group (56 per cent) than in the combined cold and mixed group (12 per cent). In 15 cases (six hot, six cold and three mixed lesions), additional MAA scans were performed immediately after arterial embolization with degradable starch microspheres (DSMs). Either complete or partial reversal of tumour vascularity was observed after DSM-embolization in five and seven cases respectively, two and two of them respectively showing native cold lesions. As tumour vascularity appears to be a prominent prognostic factor, DSM-embolization should improve the efficacy of treatment by improving liver extraction of drugs and causing flow redistribution towards hypovascular areas.

Starch microsphere‐induced arterial flow redistribution after occlusion of replaced hepatic arteries in patients with liver metastases

In four patients with major anomalies of the hepatic artery undergoing intra‐arterial chemotherapy, aberrant lobar vessels were ligated and catheters were inserted into the contralateral artery. Catheter perfusion scans performed early after ligation with 99mTc‐macroaggregated albumin (MAA) showed a defective perfusion of the lobe supplied by the occluded artery (0.43, 0.23, 0.11, and 0.28, respectively, as compared to the contralateral lobe). Further MAA scans performed after catheter infusion of 90,000,000 parts of degradable starch microspheres (DSM) showed a near normal perfusion of the ischemic lobe (0.91, 0.96, 0.87, and 0.98). On the contrary, simple MAA scans performed in the first two patients 114 and 135 days after ligation showed a still defective arterial perfusion of the ischemic lobe (0.60, and 0.24). The DSM‐induced redistribution of flow towards ischemic portions of the liver suggests a possible new role of DSM in regional treatment of liver tumors in cases with either occlusion of aberrant vessels or “hypovascular” tumors.