Background: Patients with oligometastatic disease can potentially be cured by using an ablative therapy for all active lesions. Stereotactic body radiotherapy (SBRT) is a non-invasive treatment option that lately proved to be as effective and safe as surgery in treating lung metastases (LM).However, it is not clear which patients benefit most and what are the most suitable fractionation regimes. The aim of this study was to analyze treatment outcomes after single fraction radiosurgery (SFRS) and fractionated SBRT (fSBRT) in patients with lung oligometastases and identify prognostic clinical features for better survival outcomes. Methods: Fifty-two patients with 94 LM treated with SFRS or fSBRT between 2010 and 2016 were analyzed. The characteristics of primary tumor, LM, treatment, toxicity profiles and outcomes were assessed. Kaplan-Meier and Cox regression analyses were used for estimation of local control (LC), overall survival (OS), progression free survival and distant metastases free survival (DMFS). Results: Ninety-four LM in 52 patients were treated using SFRS/fSBRT with a median of 2 lesions per patient (range: 1-5). The median planning target volume (PTV)-encompassing dose for SFRS was 24 Gy (range: 17-26) compared to 45 Gy (range: 20-60) in 2-12 fractions in fSBRT. The median follow-up time was 21 months (range: 3-68). LC rates at 1 and 2years for SFSR vs. fSBRT were 89% and 83% vs. 75% and 59%, respectively (p=0.026). LM treated with SFSR were significantly smaller (p=0.001). The 1 and 2-year OS rates for all patients were 84% and 71%, respectively. In univariate analysis treatment with SFRS, an interval of ≥ 12 months between diagnosis of LM and treatment, non-colorectal cancer histology and BED <100 Gy were significantly associated with better LC. However, none of these parameters remained significant in the multivariate Cox regression model. OS was significantly better in patients with negative lymph nodes (N0), Karnofsky performance status (KPS) >70% and time to first metastasis ≥12 months. There was no grade 3 acute or late toxicity. Conclusions: We observed good LC and low toxicity rates after SFRS for small lung metastases. Longer time to first metastasis, good KPS and N0 predicted better OS. BackgroundMetastatic progression of cancer is linked to poor prognosis and is the leading cause of cancer-related deaths (1). Few decades ago, the diagnosis of metastatic disease was related with lethal outcomes.

Background Patients with oligometastatic disease can potentially be cured by using an ablative therapy for all active lesions. Stereotactic body radiotherapy (SBRT) is a non-invasive treatment option that lately proved to be as effective and safe as surgery in treating lung metastases (LM). However, it is not clear which patients benefit most and what are the most suitable fractionation regimes. The aim of this study was to analyze treatment outcomes after single fraction radiosurgery (SFRS) and fractionated SBRT in patients with lung oligometastases and identify prognostic clinical features for better survival outcomes. Methods Fifty-two patients with 94 LM treated with SFRS or fSBRT (Cyberknife, Novalis) between 2010 and 2016 were analyzed. The characteristics of primary tumor, LM, treatment, toxicity profiles and outcomes were assessed. Kaplan-Meier and Cox regression analyses were used for estimation of local control (LC), overall survival (OS), progression free survival and distant metastases free survival (DMFS). Results Ninety-four LM in 52 patients were treated using SFRS/fSBRT with a median of 2 lesions per patient (range: 1–5). The median prescription dose for SFRS was 24 Gy (range: 17-26) compared to 48 Gy (range: 24-75) in 2-12 fractions in fSBRT. The median follow-up time was 21 months (range: 3-68). LC rates at 1 and 2 years for SFSR vs. fSBRT were 89% and 83% vs. 75% and 59%, respectively (p=0.026). LM treated with SFSR were significantly smaller (p=0.001). The 1 and 2-year OS rates for all patients were 84% and 71%, respectively. In univariate analysis treatment with SFRS, an interval of ≥ 12 months between diagnosis of LM and treatment, non-colorectal cancer histology and BED <100 Gy were significantly associated with better LC. However, none of these parameters remained significant in the multivariate Cox regression model. OS was significantly better in patients with negative lymph nodes (N0), Karnofsky performance status (KPS) > 70% and DMFS ≥ 12 months. There was no grade 3 acute or late toxicity. Conclusions We observed good LC and low toxicity rates after SFRS for small lung metastases. Long DMFS, good KPS and N0 predicted longer OS in patients with lung oligometastases.

Background: Patients with oligometastatic disease can potentially be cured by using an ablative therapy for all active lesions. Stereotactic body radiotherapy (SBRT) is a non-invasive treatment option that lately proved to be as effective and safe as surgery in treating lung metastases (LM). However, it is not clear which patients benefit most and what are the most suitable fractionation regimens. The aim of this study was to analyze treatment outcomes after single fraction radiosurgery (SFRS) and fractionated SBRT (fSBRT) in patients with lung oligometastases and identify prognostic clinical features for better survival outcomes. Methods: Fifty-two patients with 94 LM treated with SFRS or fSBRT between 2010 and 2016 were analyzed. The characteristics of primary tumor, LM, treatment, toxicity profiles and outcomes were assessed. Kaplan-Meier and Cox regression analyses were used for estimation of local control (LC), overall survival (OS) and progression-free survival.Results: Ninety-four LM in 52 patients were treated using SFRS/fSBRT with a median of 2 lesions per patient (range: 1–5). The median planning target volume (PTV)-encompassing dose for SFRS was 24 Gy (range: 17-26) compared to 45 Gy (range: 20-60) in 2-12 fractions in fSBRT. The median follow-up time was 21 months (range: 3-68). LC rates at 1 and 2 years for SFSR vs. fSBRT were 89% and 83% vs. 75% and 59%, respectively (p=0.026). LM treated with SFSR were significantly smaller (p=0.001). The 1 and 2-year OS rates for all patients were 84% and 71%, respectively. In univariate analysis treatment with SFRS, an interval of ≥ 12 months between diagnosis of LM and treatment, non-colorectal cancer histology and BED <100 Gy were significantly associated with better LC. However, none of these parameters remained significant in the multivariate Cox regression model. OS was significantly better in patients with negative lymph nodes (N0), Karnofsky performance status (KPS) >70% and time to first metastasis ≥12 months. There was no grade 3 acute or late toxicity. Conclusions: Longer time to first metastasis, good KPS and N0 predicted better OS. Good LC and low toxicity rates were achieved after short SBRT schedules.

Background: Patients with oligometastatic disease can potentially be cured by using an ablative therapy for all active lesions. Stereotactic body radiotherapy (SBRT) is a non-invasive treatment option that lately proved to be as effective and safe as surgery in treating lung metastases (LM). However, it is not clear which patients benefit most and what are the most suitable fractionation regimes. The aim of this study was to analyze treatment outcomes after single fraction radiosurgery (SFRS) and fractionated SBRT (fSBRT) in patients with lung oligometastases and identify prognostic clinical features for better survival outcomes. Methods: Fifty-two patients with 94 LM treated with SFRS or fSBRT between 2010 and 2016 were analyzed. The characteristics of primary tumor, LM, treatment, toxicity profiles and outcomes were assessed. Kaplan-Meier and Cox regression analyses were used for estimation of local control (LC), overall survival (OS), progression-free survival and distant metastases-free survival (DMFS). Results: Ninety-four LM in 52 patients were treated using SFRS/fSBRT with a median of 2 lesions per patient (range: 1–5). The median planning target volume (PTV)-encompassing dose for SFRS was 24 Gy (range: 17-26) compared to 45 Gy (range: 20-60) in 2-12 fractions in fSBRT. The median follow-up time was 21 months (range: 3-68). LC rates at 1 and 2 years for SFSR vs. fSBRT were 89% and 83% vs. 75% and 59%, respectively (p=0.026). LM treated with SFSR were significantly smaller (p=0.001). The 1 and 2-year OS rates for all patients were 84% and 71%, respectively. In univariate analysis treatment with SFRS, an interval of ≥ 12 months between diagnosis of LM and treatment, non-colorectal cancer histology and BED <100 Gy were significantly associated with better LC. However, none of these parameters remained significant in the multivariate Cox regression model. OS was significantly better in patients with negative lymph nodes (N0), Karnofsky performance status (KPS) >70% and time to first metastasis ≥12 months. There was no grade 3 acute or late toxicity. Conclusions: Longer time to first metastasis, good KPS and N0 predicted better OS. Good LC and low toxicity rates were achieved after short SBRT schedules.