Comparison of Small-Sized (70–150 μm) and Intermediate-Sized (100–300 μm) Drug-Eluting Embolics for Transarterial Chemoembolization of Small Hepatocellular Carcinomas (≤3 cm)

Purpose: To compare oncologic outcomes of transarterial chemoembolization (TACE) using 70–150-μm and 100–300-μm drug-eluting embolics (DEEs) to treat small hepatocellular carcinoma (HCC). Materials and Methods: This retrospective study included 93 patients with small HCC (≤3 cm) who underwent their first TACE with DEEs: (a) 43 with 70–150-μm DEEs and (b) 50 with 100–300-μm DEEs. Initial tumor response was assessed using per-patient and per-lesion analyses. Progression-free survival (PFS) and target tumor PFS were analyzed for patients and lesions with initial complete response (CR). Overall survival (OS) and safety outcomes were also evaluated. Results: At 1 month, initial CR rates were 72.1% in the 70–150-μm group and 70.0% in the 100–300-μm group. PFS was significantly longer in the 70–150-μm group (median, 26 months) compared with that in the 100–300-μm group (median, 11 months; log-rank P = .049), with comparable OS results (P = .096, median not reached at 36 months for either group). Per-lesion analysis found that target tumor PFS was significantly longer in the 70–150-μm group (median, 30 months) compared with that in the 100–300-μm group (median, 13 months; P = .009). Subgroup analysis revealed that the 70–150-μm group had significantly longer target tumor PFS compared with the 100–300-μm group in the 1.0–2.0-cm subgroup (P = .017), but not in the 2.1–3.0-cm subgroup (P = .117). No significant differences in adverse events were observed between the 2 groups. Conclusions: The 70–150-μm and 100–300-μm DEE-TACEs resulted in comparable tumor response and short-term safety in small HCCs (≤3 cm). However, in cases where CR was achieved, treatment with smaller microspheres demonstrated longer PFS and target tumor PFS.