Stereotactic body radiotherapy alone versus stereotactic body radiotherapy after incomplete transarterial therapy for hepatocellular carcinoma.

Introduction: We investigated the clinical outcomes of stereotactic body radiation therapy (SBRT) alone versus SBRT after incomplete transarterial chemoembolization (TACE) for a single recurrent hepatocellular carcinoma (HCC) smaller than 5 cm.

Methods: We retrospectively reviewed the medical records of patients who underwent SBRT for a single recurrent HCC ≤5 cm, without vascular invasion or extrahepatic metastasis. Patients were divided into the SBRT-alone group and the TACE-SBRT group. The primary outcome was the local control (LC) rate, and secondary outcomes were survivals and treatment-related toxicities. We additionally conducted a propensity score matching (PSM) analysis.

Results: A total of 477 patients were available for analysis. Among them, 54 patients received SBRT without prior treatment to the target lesion (SBRT-alone group), whereas 423 patients received SBRT for viable HCC after TACE (TACE-SBRT group). The 3-year LC rates did not differ between the two groups (SBRT-alone group, 88.6% vs. TACE-SBRT group, 89.6%, P = 0.918). The 3-year rates of overall survival, out-of-field intrahepatic recurrence-free survival and recurrence-free survival were also not significantly different (P = 0.479, 0.290 and 0.273, respectively). Even after PSM, LC and survival rates at 3 years were not significantly different.

Conclusion: SBRT alone demonstrated comparable local control and survival outcomes to SBRT following incomplete TACE. SBRT alone may be considered an alternative treatment option for a single recurrent HCC smaller than 5 cm when curative treatments or TACE are not feasible.