Proton radiotherapy by nirs medical cyclotron.

MORITA Shinroku, TSUNEMOTO Hiroshi, SATO Shinichiro, NAKANO Takashi, KUBOTA Susumu, FURUKAWA Shigeo, NAKAMURA Yuzuru, HIRAOKA Takeshi, KAWASHIMA Katsuhiro, KANAI Tatsuaki, ENDO Masahiro, KAWACHI Kiyomitsu

doi:10.11182/jastro1989.1.145

Clinical trials on proton radiotherapy began in November, 1979 at NIRS-Chiba. Proton beams have a highly defined dose distribution, resulting in no radiation exposure beyond the beam range and very little side scatter. Since a 70MeV proton beam penetrates about 38mm through aqueous environments, only superficial tumors and ocular neoplasms are indicated for treatment with this radiotherapy. To optimize the dose distribution, the most important factors to consider are correct positioning, reproducibility of the clinical set up, and immobilization during irradiation. For treatment, fixed horizontal or vertical beams are used. Over the past 9 years, a total of 59 patients have been treated, and some preliminary clinical results have been obtained:(1) Thirty-nine patients were treated for skin cancer, soft tissue sarcoma, malignant melanoma, etc. Local control was achieved in 67.5% using radiotherapy alone, and in 30% with salvage surgery. Skin reactions after proton irradiation were generally mild to moderate.(2) Twenty ocular neoplasms (17 malignant melanomas and 3 retinoblastomas) were treated. For melanoma, average radiation dose was TDF 137, and the result was 1 complete regression, 7 partial regressions, and 2 enucleations due to glaucoma. For retionblastoma, average dose was TDF 77, and the result was 2 complete regressions and 1 partial regression. There were no severe radiation-related complications.

Proton radiotherapy by nirs medical cyclotron.

Bibliographic Information

Search this article

Abstract

Journal

Citations (1)*help

Keywords

Details 詳細情報について

Export

Report a problem