Stereotactic body radiotherapy for primary and metastatic liver tumors — the Mayo Clinic experience
Kenneth W. Merrell, Jedediah E. Johnson, Benjamin Mou, Brandon M. Barney, Kathryn E. Nelson, Charles S. Mayo, Michael G. Haddock, Christopher L. Hallemeier and Kenneth R. Olivier
Introduction: To better understand the efficacy of liver SBRT we reviewed our prospectively collected institutional SBRT database.
Methods: Between May 2008 and March 2013, 80 patients with 104 liver lesions received SBRT. The Kaplan-Meier method estimated local control (LC), overall survival (OS). Cox proportional hazards regression models identified factors associated with LC and OS.
Results: The median follow-up for living patients was 38.6 months. Patients had primary (n=17) or metastatic (n=63) tumors. The median tumor size was 2.7 cm (range, 0.6-14.0). The 1 and 4 year rates of LC were 89.4% and 88%, respectively. Colorectal (CRC) metastasis was associated with lower rates of LC (p=0.013). OS at 1 and 4 years was 78% and 25%, respectively. Patients with CRC metastases had higher rates of OS (p=0.03). The occurrence of severe acute and late toxicity was 3.8% and 6.3%, respectively.
Conclusions: SBRT should be studied in prospective clinical trials compared with other liver-directed treatment modalities.
Keywords: stereotactic body radiotherapy, radiation therapy, liver metastasis, liver tumor, local control, radiation-induced liver disease