Skull Base Metastasis from Hepatocellular Carcinoma: Clinical Presentation and Efficacy of Radiotherapy.

Purpose: Skull base metastasis (SBM) from hepatocellular carcinoma (HCC) presents detrimental survival outcomes with cranial nerve symptoms; however, they have received little attention. This study aimed to investigate the clinical presentation and efficacy of radiation therapy (RT) in patients with SBM from HCC. Patients and Methods: We identified patients with SBM from HCC in Yonsei Cancer Center from 2005 to 2019. Image evaluations and SBM-related symptoms were reviewed. Overall survival was calculated using the Kaplan-Meier method and compared through the Log rank test. The oligometastasis group included patients with less than five foci of tumors, while the extensive metastasis group presented five or more sites. Results: The incidence of SBM from HCC was 1.5% (58/3793 patients), commonly found in the middle cranial fossa. SBM associated symptoms presented in 51 patients, and the most common were head and neck area pain, and orbital symptoms, The palliation rate after RT was 65% (24/39 patients) for overall symptoms and 83.3% (20/24 patients) for cranial nerve symptoms. In whole cohort, overall survival was analyzed, and the median overall survival of patients with oligometastasis was better than extensive metastasis (23.7 months vs 1.8 months, p < 0.001). In subgroup who received RT (39 patients), the median overall survival was 23.7 and 2.7 months for patients with oligo and extensive metastasis, respectively (p < 0.001). Conclusion: This study confirmed clinical features of SBM from HCC. Overall survival was generally poor, but patients presenting oligometastasis seemed to have possibility of relative long-term survival. Although radiation was effective in SBM-induced symptom relief, dose-response relationship in local control rate and overall survival needs further studies with larger number of patients.