Iodized oil accumulation in the hypovascular tumor portion of early-stage hepatocellular carcinoma after ultraselective transcatheter arterial chemoembolization.
OBJECTIVE
We evaluated iodized oil accumulation in the hypovascular portion of early-stage hepatocellular carcinoma (HCC) after ultraselective transcatheter arterial embolization (TACE).


METHODS
Forty-seven HCC lesions with hypovascular portions were treated by TACE at the distal level of the sub-subsegmental artery of the liver. Portal blood in the hypovascular portion was classed in two grades by computed tomography (CT) during arterial portography: decreased and preserved. Iodized oil accumulation was classed into three grades on CT obtained 1 week after TACE: (1) dense accumulation in the almost entire tumor, including the hypovascular portion (grade 2); (2) dense accumulation in hypervascular portions but sparse accumulation in hypovascular portion (grade 1); and (3) sparse accumulation or no accumulation (grade 0). Findings on serial follow-up CT images were also analyzed.


RESULTS
Portal blood in the hypovascular portion was decreased in 32 lesions, and preserved in 15 lesions. On CT 1 week after TACE, 32 tumors (68.1%)-23 with decreased portal blood and 9 with preserved portal blood-were classed as grade 2. Twelve tumors (25.5%), six with decreased portal blood and six with preserved portal blood, were classed as grade 1. Three tumors (6.4%) with decreased portal blood were classed into grade 0. In total, 25 tumors (53.2%), 22 in grade 2 and 3 in grade 1, were well controlled by ultraselective TACE during the mean follow-up of 15.8 months.


CONCLUSIONS
Iodized oil accumulation and retention in the hypovascular portion of early-stage HCC was frequently observed after ultraselective TACE, mainly in the hypovascular portion with decreased portal blood.
Miyayama
Shiro
S
Department of Diagnostic Radiology, Fukuiken Saiseikai Hospital, 7-1, Funabashi, Wadanaka-cho, Fukui, 918-8503, Japan, s-miyayama@fukui.saiseikai.or.jp.
Matsui
Osamu
O
Yamashiro
Masashi
M
Ryu
Yasuji
Y
Takata
Harumi
H
Takeda
Taro
T
Aburano
Hiroyuki
H
Shigenari
Noriaki
N