Fig. 2

Kaplan-Meier curves showing the overall survival after GKRS1 between different groups in relation to IT or TT. A Patients with IT or TT at or after GKRS1 had a significantly longer survival after GKRS1 (21/70 or 30%, 11.2 months, 95% CI = 3.1–19.4) compared to patients without IT or TT at or after GKRS1 (50/71 or 70%, 3.7 months, 95% CI = 0.8–6.6, p = 0.005). B Among patients with KPS ≥ 80%, patients with IT or TT (13.4 months, 95% CI = 8.4–18.5) showed a significantly longer median overall survival after GKRS1 compared to those without IT or TT (6.3 months, 95% CI = 3-9.7, p = 0.012). C In the group of patients ≤ 65 years, those with IT or TT at or after GKRS1 (11.2 months, 95% CI = 4.3–18.2) showed a significantly longer median overall survival compared to patients without IT or TT (2.6 months, 95% CI = 0.3–4.9, p = 0.017). D Analyzing patients with multiple BM at GKRS1, we could show that those with IT or TT at or after GKRS1 (7.3 months, 95% CI = 0-14.6) showed a significantly longer median overall survival after GKRS1 compared to patients without IT or TT (2.3 months, 95% CI = 1.2–3.4, p = 0.009). E Among patients with ECM at diagnosis of BM, those with IT or TT at or after GKRS1 (11.2 months, 95% CI = 2.8–19.7) showed a significantly longer median overall survival after GKRS1 compared to patients without IT or TT (4.4 months, 95% CI = 0.7–8.1, p = 0.002). F Among female patients, those with IT or TT at or after GKRS1 (19.1 months, 95% CI = 11.1–27) showed a significantly longer median overall survival after GKRS1 compared to patients without IT or TT (2.7 months, 95% CI = 0-7.2, p = 0.003). BM brain metastasis, CI Confidence Interval, ECM extracranial metastases, GKRS Gamma Knife Radiosurgery, IT immunotherapy, KPS Karnofsky performance status scale, TT targeted therapy