Little is known about whether the types of chemotherapeutic agents affect the efficacy of transarterial chemoembolization in patients with hepatocellular carcinoma. Although doxorubicin is the most commonly-used chemotherapeutic agent in the world, idarubicin is recently in the spotlight after promising results of the in vitro and prospective single-arm studies. On the other hand, there are many reports showing that the type of chemotherapeutic agents does not significantly alter the efficacy of transarterial chemoembolization. This is a randomized-controlled trial to show the non-inferiority of idarubicin compared to doxorubicin in patients with hepatocellular carcinoma who receive transarterial chemoembolization as the first-line treatment.

Eligible patients will be randomly allocated either in the IDA-cTACE or DOX-cTACE group, and the randomization can be stratified by Child-Pugh class. Each patient will be treated by conventional chemoembolization using a microcatheter and chemoemulsion. For the chemoemulsion preparation method, 10 mg of idarubicin powder (IDA-cTACE) or 50 mg of doxorubicin powder (DOX-cTACE) will be dissolved by 2.5 mL of iodinated contrast media, and then mixed with 10 mL of iodized poppy seed oil (Lipiodol; Lipiodol Ultrafluid, Guerbet, France). The amount of chemoemulsion administered to each patient will be determined by an operator regarding tumor size, vascularity, etc. Additional embolization will be performed using calibrated gelatin sponge particles usually 100-350 µm until the arterial flow is almost stopped. Afterwards, Patients will be evaluated at 1, 3, and 6 months after the initial treatment, but the follow-up can be individualized at the discretion of hepatologists or hepatic surgeons blinded to the treatment allocation. In cases of residual or recurred tumor, additional treatments will be determined by the blinded hepatologists or hepatic surgeons. Once a patient with residual or recurred tumor receives repetitive TACE, the same drug (idarubicin or doxorubicin) used at the initial TACE will be used for re-treatments.

Inclusion Criteria:

1. Adults aged 19 or above.

2. Patients diagnosed with HCC either histologically and/or radiologically (LI-RADS 4 or 5).

3. Patients with five or fewer tumors.

4. Patients in which the largest tumor is 5 cm or less in diameter.

5. Patients with no prior treatment experience for HCC.

6. Patients categorized as Child-Pugh class A or B.

7. Patients with an Eastern Cooperative Oncology Group performance status of 2 or below.

8. Patients without severe functional abnormalities of major organs: the following results from a blood test conducted within a month prior to the procedure must be satisfied:

   • WBC count ≤ 12,000 / mm3
   • Absolute neutrophil count ≥ 1,500 /mm3
   • Hemoglobin ≥ 8.0 g/dL
   • Total bilirubin ≤ 3.0 mg/dL
   • eGFR ≥ 30 mL/min/1.73 m2
   • Patients deemed clinically most suitable to receive TACE through hepatologist, hepatic surgeon, or multidisciplinary consultation: patients for whom other treatments such as liver transplantation/surgery/ablation are realistically impossible or, even if technically possible, do not have significant clinical benefits compared to TACE.
   • Patients who have understood sufficiently about this clinical trial and have given written consent to participate.
   • Fertile women capable of effective contraception for at least 6.5 months after TACE, and men with fertile female partners capable of effective contraception for at least 3.5 months after TACE.

Exclusion Criteria:

1. Patients with HCC involving the portal vein or hepatic vein.
2. Patients with extrahepatic spread of HCC
3. Patients diagnosed with a cancer other than HCC within 2 years of enrollment.
4. Patients who have undergone a biliary-intestinal anastomosis.
5. Patients for whom the use of idarubicin or doxorubicin is contraindicated (including severe heart failure, arrhythmia, hypersensitivity to anthracycline chemotherapy, pregnant or nursing women, etc.).