Interstitial radiotherapy for malignant melanoma of the choroid: implantation of radioactive gold grains by means of a gun-shaped applicator

Four years after enucleation of one eye of a 49-year-old patient because of malignant melanoma of the choroid, the same kind of tumor developed in the remaining eye. The size of the melanoma and its location close to the pole prompted an unconventional therapeutic approach. After external beam radiation a radioactive gold seed sheathed with platinum was deposited directly above the tumor through the hollow needle of a pistol-shaped applicator, thus increasing the radiation dose to the required 8,500 rad, which is considered sufficient for realiable destruction of malignant melanoma. After a one-year period of observation the patient is still in good health, the melanoma having been replaced by a flat chorioretinal scar; the surrounding retina, as well as the optic nerve and the lens lack any sign of radiation damage. Visual acuity of 0.8/Jg I has been preserved. The technique and possible indications for treatment by this method are described. (orig.)