Stereotactic Body Radiation Therapy (SBRT) for Liver Oligometastases: Outcomes and Safety

Abstract

Objective. The aim of this study was to investigate adverse effects, progression free survival (PFS), one-year local control (LC) and one-year overall survival (OS) of patients with liver oligometastases treated with stereotactic body radiotherapy (SBRT), and whether there was a significant difference in these parameters in patients with primary colorectal cancer compared to other tumor localizations.

 Patients and Methods. Patients were simulated using four-dimensional computed tomography (4DCT). Using volumetric modulated arc therapy (VMAT) technique, SBRT was performed on 16 patients with <3 liver metastases. The prescribed dose was 60 Gy in 8 fractions (BED 105 Gy). Cone beam CT (CBCT) was used for image guidance before each frac­tion with online correction.

Results. There were no adverse effects. Median PFS for all patients, patients with primary colorectal cancer, and patients with primary non-colorectal cancer was 11 months (SE 2.1), 16 months (SE 2.8), 6 months (SE 2.4), re­spectively. There was no significant difference in the PFS for these two observed groups (P=0.09). The one-year LC was 62.5%. Patients with primary colorectal cancer had one-year LC of 87.5%, while the group of patients with primary non-colorectal cancer had one-year LC of 37.5% (P=0.063). The total one-year OS was 87.5%. In the group of patients with primary colorectal cancer, the one-year OS was 100%, while in the group of patients with primary non-colorectal cancer, the one-year OS was 75% (P=0.317).

Conclusion. SBRT with 8 × 7.5 Gy can be safely delivered and is effective method of treating liver oligometastases.