Optimal lipiodol volume in transcatheter arterial chemoembolotherapy for hepatocellular carcinoma: study based on lipiodol accumulation patterns and histopathologic findings.

To clarify the optimal dose of Lipiodol (Andre Guerbet, Aulnay-sous-Bois, France) during Lipiodol-transcatheter arterial embolization (L-TAE) and segmental L-TAE used to treat hepatocellular carcinoma, we studied the relationship between the volume of Lipiodol used during these procedures and the necrosis rates in resected specimens, as well as the correlation with the Lipiodol accumulation pattern based on the computed tomography findings (L-CT) and the volume of Lipiodol in resected and nonresected cases after L-TAE or segmental L-TAE. The L-CT and the dose of Lipiodol injected (mL) were studied correlatively in 198 cases (28 resected cases and 170 nonresected cases; tumor size < or = 5 cm in 52 cases and > 5 cm in 118 cases) that underwent L-TAE and in 80 cases (14 resected cases and 66 nonresected cases, tumor size < or = 5 cm in 52 cases and > 5 cm in 14 cases) that underwent segmental L-TAE. The L-CT was classified into four types: type I, homogeneous accumulation (type Ia, accumulation around the tumor; type Ib, no accumulation around the tumor); type II, partial defect; type III, sporadic accumulation; and type IV, punctate or no accumulation. In the 42 resected cases (L-TAE, 28 cases; segmental L-TAE, 14 cases), type I was seen in 68% (Ib, 100%) of the L-TAE cases and 93% (Ia, 79%; Ib, 14%) of the segmental L-TAE cases. The necrosis rate of the cases with type Ib L-CT was 90% to 100%, and all type Ia cases showed complete necrosis. In the 236 nonresected cases (L-TAE, 170 cases; segmental L-TAE, 66 cases), the volume of Lipiodol injected correlated with the L-CT type. In the L-TAE cases with a tumor size < or =5 cm, the frequency of the injected Lipiodol volume (D) being greater than the tumor diameter (d) (D > or = d) was 90%, and 87% of the cases with D > or = d showed type Ib L-CT. In the group whose tumor diameter (d) was more than 5 cm, the frequency of D > or = d was 25%, and 70% of the cases of D > or = d were type Ib. The frequency of D < d was 75%, and in 13% of these cases the L-CT was type Ib and the maximum dose was approximately 10 mL. In segmental L-TAE using the same dose of Lipiodol as in L-TAE, the frequency of D > or = d was 83%, and 93% of those cases showed type I, including 85% of type Ia. There was a correlation between the L-CT type and the necrosis rate, and type I, especially Ia in segmental L-TAE, showed complete necrosis in almost all cases. In L-TAE, standards for the optimal dose of Lipiodol are thought to be as follows: D > or = d in cases with d < or = 5, and slightly D < d and 10 mL maximally in cases with d > 5. In segmental L-TAE using the same dose of Lipiodol as in L-TAE, enhancement of the therapeutic effect was seen compared with L-TAE. This is surmised to have been because of the higher Lipiodol volume with anticancer agents per unit volume of the tumor in segmental L-TAE.