Radiotherapy and inflammaging: the influence of prostate cancer radiotherapy on systemic inflammation

PURPOSE: The present study was performed to investigate the association of prostate cancer radiotherapy with inflammaging(definition), a condition characterized by the elevation of inflammatory blood parameters that significantly increases the susceptibility to the occurrence or progression of age-related conditions. PATIENTS AND METHODS: A total of 306 patients treated with curative radiotherapy (RT) for prostate cancer were enrolled into the prospective study. Aging-related inflammatory parameters including C-reactive protein (CRP), albumin, fibrinogen, cholesterol, platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte ratio (NLR) were analyzed before and at the end of RT, and 3 and 15 months after completion of the RT. Statistical analysis was performed using non-parametric variance analysis. RESULTS: Overall variance analysis showed a significant influence of RT on all inflammatory parameters (p < 0.001) with the exception of CRP (p = 0.498). Pairwise analysis revealed a significant elevation of fibrinogen (p = 0.041), NLR (p < 0.001), and PLR levels (p < 0.001) as well as a significant decrease of albumin (p < 0.001) and cholesterol levels (p < 0.001) during the RT course. After completion of RT, a significant recovery was detected for NLR, PLR, albumin and cholesterol. However, 15 months after RT, PLR, fibrinogen, and cholesterol remained significantly lower when compared to the baseline (p < 0.001). CONCLUSION: Our results indicate that radiation therapy triggers chronic inflammatory processes that could contribute to the development, acceleration or worsening of age-related alterations and conditions. Further investigations to estimate the long-term consequences of curative radiation therapy on clinical manifestations of aging are warranted.