Use of fructose 1,6-diphosphate aldolase to detect tumour necrosis after transcatheter arterial embolization of hepatocellular carcinoma.

Transcatheter arterial embolization (TAE) is a popular and well-established devascularization treatment modality for hepatocellular carcinoma (HCC). The persistent retention of lipiodol on follow-up computed tomography (CT) scan and time-dependent decrease in size of the lipiodol-stained area of tumour after TAE does not reveal the biological death of tumour cells. Moreover, it is difficult to clinically evaluate the effective necrosis of tumour cells by TAE in cases of HCC that do not produce alpha-fetoprotein (AFP). We therefore studied the release of a relatively tumour-specific protein by the necrotic hepatoma cells to evaluate the effectiveness of TAE. Transcatheter arterial embolization was performed in 17 patients with the imaging diagnosis of HCC; either superselective (n = 6) or non-superselective (n = 11) techniques were used. We measured serum levels of relatively tumour-specific fructose 1,6-diphosphate (FDP) aldolase and non-tumour-specific fructose 1-phosphate (F1P) aldolase by substrate-specific enzymatic methods. Enzyme activities were performed before and after TAE. The time-dependent decrease in size of the lipiodol-stained areas was studied on follow-up CT scans after TAE. Pre- and post-treatment serum AFP levels were determined by radio-immunoassay. The six cases of superselective TAE underwent marked tumour regression by CT compared with the 11 cases of non-superselective TAE. Fructase 1,6-diphosphate aldolase output correlated well with post-necrotic tumour regression after TAE (r = 0.87, P= 0.001). The elevation of serum FDP aldolase was also significantly associated with a decrease in serum AFP (r = 0.72, P < 0.01). In contrast, serum F1P aldolase output was inversely correlated with either tumour regression or serum AFP concentrations after TAE. The serum levels of the tumour-specific enzyme FDP aldolase correlated significantly with effective tumour necrosis and consequent tumour regression after TAE. We suggest that measurement of FDP aldolase activity in serum after TAE can be used clinically to detect the degree of tumour necrosis by TAE.