悪性腫瘍による閉塞性黄疸に対しての金属性ステントを用いた姑息的減黄術はtumor ingrowthによるステント閉塞の問題が増加している。本研究では, チタン合金ステントに超音波を照射し, ラジカルの産生を利用したステント内再閉塞を予防・改善するための無侵襲的治療法の確立を目的とした。チタン合金に対し1MHzの超音波を30秒0.3W/cm2照射し超音波のみと比較したところ, チタン合金で高いフリーラジカルの発生が確認され殺細胞効果も最も高かった。悪性腫瘍ステントモデルでは, 1MHｚ, 0.3W/cm2, 10分の超音波照射を行った。超音波照射群でステントへのingrowth抑制が確認された。
Palliative biliary drainage using a metallic stent is performed for biliary obstruction by unresectable biliary carcinoma. The biggest issue of biliary stenting therapy is re-obstruction due to tumor ingrowth. The generation of hydroxyl radical was reported during ultrasonic irradiation (US) in the presence of TiO2. The metal stent for biliary drainage is made of titanium alloy, and it could generate hydroxyl radicals with US. The aim of this study was to investigate a novel prevention method for re-obstruction using ultrasonic irradiation.
Higher free radical generation and cytocidal action were observed with titanium alloy with US than US alone. The stent re-obstruction nude mice model which were a stent implanted to the neighborhood of tumor were given 10 minutes US of 1000 KHｚ, 0.3W /&#13216 ; once a day for 14 days. Tumor ingrowth to the stent was seen in the non-irradiation group and it was inhibited in the irradiation group.

研究種目 : 基盤研究(C)
研究期間 : 2012～2014
課題番号 : 24501355
研究分野 : 外科学