Improved oncologic outcomes by ablative radiotherapy in patients with bone metastasis from hepatocellular carcinoma.

Abstract

For bone metastasis from hepatocellular carcinoma (HCC), radiotherapy (RT) has been used a palliative treatment with little impact on survival. Currently, ablative RT is popularly used, and a more than palliative effect is expected. Herein, we investigated the clinical efficacy of ablative RT in patients with bone metastasis from HCC. In total, 530 patients with 887 lesions treated in 1992-2019 were reviewed. Oligometastasis was defined as the presence of < 5 lesions. Total doses were normalized to obtain biologically effective doses (BEDs). The cut-off threshold of the BED was determined via receiver operating characteristics curve analysis. The Kaplan-Meier method was used to calculate overall survival (OS); propensity score matching (PSM) was performed to balance the heterogeneity in cases while comparing BEDs of ≥ 60 and < 60Gy. The most common site of metastasis was the spine (59%); 59 patients (11%) presented with oligometastasis, and 76.2% of patients showed objective pain palliation after RT. Median OS was 5.1months for all patients; patients with oligometastasis showed longer OS than those without (9.8 vs. 4.7months). A Cox proportional hazards model showed that performance status, Child-Pugh class, extraosseous metastasis, primary HCC status, α-fetoprotein level, and radiation dose (BED) were significant prognostic factors. Post PSM, BED was the only treatment-related prognostic factor that remained significant; the median OS durations were 8.1 and 4.4months when the BEDs were ≥ 60 and < 60Gy, respectively. Ablative RT improved OS and pain palliation in patients with bone metastasis from HCC.