Drug‐eluting bead transarterial chemoembolization with medium‐sized versus small‐sized CalliSpheres microspheres in unresectable primary liver cancer

PURPOSE: The optimal microparticle size for drug‐eluting beads transarterial chemoembolization (DEB‐TACE) remains unknown. This retrospective cohort study analyzed the efficacy and safety of CalliSpheres microsphere embolization in the treatment of unresectable hepatocellular carcinoma (HCC) to determine the influence of particle size on the results. PATIENTS AND METHODS: Forty‐two patients with unresectable HCC were enrolled in this retrospective study from January 2018 to January 2020. Patients received DEB‐TACE with CalliSpheres of 100–300 μm (small‐size, n = 15) or 300–500 μm (medium‐size, n = 27). The tumor response was evaluated via enhanced CT or MRI at 1 month, 3 months, and 6 months after treatment, based on the Modified Response Evaluation Criteria in Solid Tumors. Adverse events after DEB‐TACE were recorded. RESULTS: Complete response, partial response, stable disease, and progressive disease were recorded in 20%, 20%, 33.3%, 26.7%, respectively, of patients in the small‐size group and 3.7%, 25.9%, 44.4%, 25.9% of patients in the medium‐size group, respectively. No significant difference was found between the two groups (p = 0.516). Major adverse events, including grade three liver toxicity (n = 4) and liver abscess (n = 3), occurred significantly more in the small‐size group, while none were reported in the medium size group (p < 0.05). CONCLUSION: DEB‐TACE with medium‐size (300–500 μm) CalliSpheres microspheres had similar efficacy and a better safety profile than DEB‐TACE with small‐size (100–300 μm) CalliSpheres, indicating that medium‐size microspheres may be a better choice for unresectable primary liver cancer.