Clinical experience of proton radiotherapy for ocular melanocytoma

Seventy MeV proton beam irradiation has been used for the treatment of superficial tumors since 1979 at NIRS. The physical characteristics of protons, namely Bragg peak of the ionization offers the posibility of highly localized dose distribution which has clinical advantages in the field of ocular radiotherapy. To arrest the progressive symptomes of melanocytoma in the optic disk on a female patient, 30 Gy of proton radiation delivered in 3 fractions over 28 days (TDF 80). In spite of a short follow-up period, the lesion showed depigmentation and the field of vision improved slightly. No side effect were ovserved. The radiation planning method and the treatment techniques of proton radiotherapy were also discussed. (author)