Radiation-induced acute phase reaction: correlation between radiation-induced proctitis and increased hepcidin serum levels

Purpose

To analyse hepcidin serum and urine levels during radiotherapy for prostate cancer.

Methods

In 18 patients undergoing radiotherapy for prostate cancer, blood, plasma, and urine samples were taken before and during radiotherapy. Complete blood cell count, pro-hepcidin-, ferritin-, transferrin-, IL–1β-, IL–6-, and TNF-α concentration was determined. Pro-hepcidin concentration was additionally measured in urine samples. Toxicity was evaluated weekly. Differences among tested factors were tested by Wilcoxon Rank Sign Test for paired data.

Results

In 10 patients developing acute radiation-induced proctitis, a significant increase in pro-hepcidin, IL–6, and TNF-α plasma levels (p<0.05) was detected. Pro-hepcidin urine levels also showed a strong trend towards increase (p=0.06). Concurrently, hemoglobin, and leucocytes were significantly decreased in the patients with acute proctitis (p<0.05). In 8 patients showing no symptoms of proctitis, solely a significant decrease for leucocytes was detected. Additive, these patients showed a significant increase of ferritin, and a decrease of transferrin levels (p<0.05).

Conclusions

Hepcidin levels are increased and hemoglobin is decreased during radiotherapy for prostate cancer in patients who develop acute proctitis. Radiation-induced expression of cytokines may be responsible for increased hepcidin expression in the liver. Regulation of iron metabolism by hepcidin may be an underestimated response in radiotherapy.

cytokines - hepcidin - proctitis - prostate cancer - radiotherapy