VEGF and IL-6 correlation in POEMS a potential upcoming marker of active disease and early autologus BMT response

Introduction: VEGF function may be responsible for most POEMS manifestations, and it is considered a reliable marker of disease. COVID-19 era arose increasing interest for other inflammatory cytokines, with particular focus on Interleukin-6; VEGF production is stimulated by IL-6 and IL1β, whose concentrations appear to be elevated in clonal plasma cells. Objectives: This study aims to simultaneously evaluate VEGF and IL-6 values in patients (pts) with POEMS at different stages of the disease to find a correlation between them. Methods: We performed a monocentric study, measuring serum levels of VEGF and IL-6 in 8 POEMS pts at different time points of the disease. Results: We observed elevated serum levels of both VEGF and IL-6 in three pts before transplant, while the day after the infusion of autologous stem cells, we observed a steep decrease of both serum markers. Among the four-pts tested only after transplant, two presented with a consensual level of VEGF and IL-6, while the others did not correlate. One patient observed at POEMS diagnosis, during active disease, presented with strikingly high levels of both serum markers. Conclusions: So far, to the best of our knowledge, IL-6 could be considered as a marker of active disease and reliable up to the very first months after BMT, after which its accuracy appears to be lost due to unknown factors, still to be investigated.