Abstract
Background
Radiotherapy may work synergistically with immunotherapy and targeted agents. We aimed to assess the safety and outcomes of stereotactic body radiotherapy (SBRT) plus non-first-line programmed death-1 (PD-1) inhibitors and targeted agents (TA) in metastatic renal cell carcinoma (mRCC).
Methods
We retrospectively reviewed 74 patients treated with non-first-line PD-1 inhibitors plus TA in non-first-line setting. Survival outcomes were calculated from the anti-PD-1 treatment using the Kaplan–Meier method. Univariate and multivariate analyses were performed by Cox proportional hazards models.
Results
Thirty-two (43.2%) patients received anti-PD-1/TA therapy alone (anti-PD-1/TA alone group), and 42 (56.8%) received SBRT in addition (anti-PD-1/TA + SBRT group). The median duration of first-line therapy was 8.6 months. Patients in the anti-PD-1/TA + SBRT group had significantly longer overall survival (OS) (38.5 vs 15.4 months; P = 0.022). On multivariate analysis, oligometastasis, ECOG performance status 0–1, anti-PD-1/TA + SBRT, and duration of first-line therapy ≥ 8.6 months were predictors for OS. The addition of SBRT was associated with improved OS in patients with clear-cell type (HR 0.19; 95% CI 0.07–0.55; P = 0.002) and duration of first-line therapy ≥ 8.6 months (HR 0.22; 95% CI 0.06–0.88; P = 0.032). Grade ≥ 3 toxicities occurred in 23 patients (54.8%) in the anti-PD-1/TA + SBRT group, and in 21 patients (65.6%) in the anti-PD-1/TA alone group.
Conclusions
Incorporating SBRT into anti-PD-1/TA therapy is safe and tolerable. Further investigation is needed, particularly in patients with clear-cell histology and a longer duration of response to first-line antiangiogenic therapy.
First results of safety profile of nivolumab (NIVO) in combination with stereotactic body radiotherapy (SBRT) in II and III line of patients (pts) with metastatic renal cell carcinoma (mRCC) in NIVES study
