Background: Pain is experienced by 50-75% of patients with bone metastases, representing a major source of morbidity amongst cancer patients. Magnetic resonance-guided high intensity focused ultrasound (MRgHIFU) is a new, non-invasive, outpatient treatment modality for painful bone metastases. The aim of this study was to analyze urinary cytokines/chemokines pattern after MRgHIFU for palliative treatment of painful bone metastases. The findings were compared to the cytokines/chemokines pattern post single 8 Gy fraction radiation from our previous study.
Methods: Urine samples were collected from patients with painful bone metastases 3 days before and 2 days after treatment with MRgHIFU. Each urine sample was tested for pro-inflammatory cytokines and anti-inflammatory cytokines. Patients received teaching on how to collect urine samples on their own. The Millipore Milliplex 42-Plex Cytokine/Chemokine Kit™ was used to measure urinary levels of a panel of cytokines/chemokines.
Results: Ten patients were enrolled for the study. The following 15 cytokines were above the level of detection (LOD) in at least 50% of patients at both pre MRgHIFU and post MRgHIFU: EGF, eotaxin, Fit-3 ligand, fractalkine, G-CSF, GRO, IFNα2, IL-1ra, IL-8, IP-10, MCP-1, PDGF-AA, RANTES, sIL-2Rα, and VEGF. Nine urinary cytokines significantly decreased post MRgHIFU, namely, eotaxin, GRO, IL-8, IL-13, IP-10, MCP-1, MIP-1β, RANTES, and sIL-2Rα. In addition, there were significant differences between post MRgHIFU and post-8 Gy fraction radiation in most urinary cytokines.
Conclusions: Nine urinary cytokines significantly reduced post-MRgHIFU in patients with painful bone metastases. The significance of cytokines/chemokines pattern for palliative treatment of painful bone metastases is still unknown.
Keywords: Bone metastases; cytokines/chemokines; magnetic resonance-guided high intensity focused ultrasound (MRgHIFU); palliative treatment.