Bone metastases treated with immune checkpoint inhibitors: A single center experience.
e14105 Background: We conducted a retrospective study to analyze the overall survival (OS) and progression free survival (PFS) among patients with bone metastases (BMs) from Non Small Cell Lung Carcinoma (NSCLC), Melanoma, Head and Neck Squamous Cell Carcinoma (HNSCC) and others (including genitourinary carcinoma) treated with immunotherapy (Nivolumab, Pembrolizumab, Ipilimumab or a combination). Methods: We retrospectively evaluated patients with BMs treated at our institute from 2012-2017 who received either immunotherapy alone or in combination with other therapies for BMs including: medical therapy (zoledronic acid or denosumab), radiation or surgery. Univariate analysis was utilized to analyze OS and PFS. Results: A total of 58 patients were identified, median age at diagnosis of BMs was 61 years (range 29 – 94). 39 patients were male (67.2%) and 47(81%) patients had good performance status (KPS 70-100) at the time of immunotherapy initiation. The median time to diagnosis of BMs was 11.4 months. 20 patients had a single BM, 16 had 2-4 BMs and 22 had ≥5 BMs. Axial-only BMs were seen in 27 patients, appendicular-only in 8 and both in 23 patients. 40 patients were symptomatic and 28 patients had skeletal events (pathological fractures, spinal cord compression or hypercalcemia). 51 patients had other metastatic sites at the time of initiation of immunotherapy. 25 patients received nivolumab, 20 patients received pembrolizumab and 4 patients received combination immunotherapy. 41 patients received additional treatments for BMs. The median OS from the start of immunotherapy was 5.15 months and median PFS was 3 months. On univariate analysis male sex (p = 0.03) and combination immunotherapy (p = 0.06) were associated with better OS. Patients who received additional treatments for BMs (p = 0.04) and combination immunotherapy (p = 0.02) had better PFS. Conclusions: Combination immunotherapy and use of additional treatment modalities for BMs is associated with better survival. Further analysis is required to validate these results. [Table: see text]