奥山 伸男¹, 笹本 修一¹, 加藤 信秀¹, 高木 啓吾¹, 山崎 史朗¹, 辻本 志朗², 弓田 長彦³, 西垣 隆一郎³, 佐々木 一昭⁴, 梅村 晋一郎⁴

Nobuo OKUAYMA ¹, Syuichi SASAMOTO¹, Nobuhide KATOU ¹, Keigo TAKAGI¹, Shirou YAMAZAKI ¹, Shirou TUJIMOTO², Nagahiko YUMITA³, Ryuichiro NISHIGAKI³, Kazuaki SASAKI⁴, Shinichiro UMEMURA⁴

¹東邦大学医学部胸部心臓血管外科, ²病院病理, ³東邦大学薬学部, ⁴日立製作所中央研究所

¹Department of Thoracic Cardiovascular Surgery, Toho University School of Medicine, 6-11-1 Omorinishi, Tokyo 143, Japan, ²Department of Pathology, Toho University School of Medicine, 6-11-1 Omorinishi, Tokyo 143, Japan, ³Department of Pharmacology, Toho University School of Pharmaceutical Science, 2-2-1 Miyama, Funabashi-shi, Chiba 274-8570, Japan, ⁴Center Research Laboratory, Hitachi Co., Ltd., Higashikoigakubo, Kokubunji-shi, Tokyo 185-8601, Japan

キーワード : Breast cancer, Hematoporphyrin derivative, Photodynamic therapy, Sonodynamic therapy, Ultrasound

Sonodynamic therapy is a target therapy that destroys cancer by ultrasound and leaves hematoporphyrin derivative (HpD) intact. We administered this therapy to rats with breast cancer chemically induced by DMBA. Tumor volumes of four treatment groups of rats were compared. The first group was treated only with administration of hematoporphyrin D; the second, with ultrasound irradiation alone; and the third, with a combination of hematoporphyrin D and ultrasound irradiation. The fourth group, the controls, received no treatment. Ultrasound irradiation alone slightly suppressed tumor growth, while hematoporphyrin D alone had no inhibitive effect on tumor growth. Suppression of tumor growth by combined administration of hematoporphyrin D and ultrasound irradiation was remarkable, however. Destruction of tumor tissue was also observed by light microscopy in the cases treated with combined ultrasound irradiation and HpD. We confirmed that the concentration of HpD was higher in the tumor tissue than in the surrounding tissue of the DMBA rats. Sonodynamic therapy appears to offer great promise as a treatment for breast cancers and other cancers that occur near the surface of the body.