61. Cytokine Responses Detected in Blood from Cancer Patients Given X-ray or Carbon Ion Therapy

Shigeru Yamada, Tadashi Kamada and Hiroshi Tsuji.

Keywords: x-ray therapy, carbon ion therapy, cytokines

Ionizing radiation induces an acute inflammatory response in many normal cells and tissues. Exposure of cells to irradiation induces some cytokines such as tumor necrosis factor-alpha (TNF-) and interleukin-6 (IL-6). Heavy ions are reported to have several advantages compared to conventional photon therapy, including a better physical dose distribution and a higher biological efficiency in tumor cell killing. However there are few data on biological responses in patients treated with heavy ions compared to photon therapy. In this study we examined cytokine responses induced by carbon ions and X-ray irradiation. We measured inflammatory cytokines such as IL-4, IL-6, IL-8, TNF- and INF-. Blood samples from patients with esophageal cancer were obtained before and after treatment. No significant differences in the response of these cytokines from the patients treated with X-rays were detected. On the other hand IL-4, IL-8 and TNF- displayed similar response with X-rays, however the secretion of IL-6 and INF- was induced by the carbon ions. These results suggested cytokine responses differ between X-rays and carbon ions.