Survival and prognostic factors in 321 patients treated with stereotactic body radiotherapy for oligo-metastases.

Abstract

To establish a model to predict survival after SBRT for oligo-metastases in patients considered ineligible for surgical resection (SR) and radiofrequency ablation (RFA). Overall survival (OS) rates were estimated in 321 patients treated for 587 metastases with SBRT over 13years. Patients were treated for a variety of metastasis types with colorectal cancer (CRC) being the most frequent (n=201). With a median follow-up time of 5.0years, the median OS was 2.4years (95% CI 2.3-2.7) and the survival rates were 80%, 39%, 23% and 12% at 1, 3, 5 and 7.5years after SBRT, respectively. WHO performance status (PS) (0-1) (HR 0.49; p<0.001), solitary metastasis (HR 0.75; p=0.049), metastasis ⩽30mm (HR 0.53; p<0.001), metachronous metastases (HR 0.71; p=0.02) and pre-SBRT chemotherapy (HR 0.59; p<0.001) were independently related to favorable OS. Median OS rates were 7.5, 2.8, 2.5, 1.7 and 0.8years with 0, 1, 2, 3, ⩾4 unfavorable prognostic factors, respectively. The treatment-related morbidity was moderate. However, three deaths were possibly treatment-related. Prognostic factors may predict long-term survival in patients with oligo-metastases treated with SBRT.