[Optimization of irradiation time in the treatment of malignant melanoma of the choroid with beta applicators (106Ru/106Rh)].
Brachytherapy with 106Ru/106Rh necessitates protracted irradiation because the applicators have to be sutured to the sclera. Protracted radiotherapy causes more intensive damage in tumor cells with increased metabolism and a higher mitosis rate than in normal tissue. Beta irradiation of rabbit eyes with 0.258-0.231 Gy/min produced more extensive exudative reactions and morphological damage of the retina than a lower dosage rate with 0.035-0.026 Gy/min and the same total dose of 650 Gy. For the study reported here 75 patients suffering from choroidal melanoma and irradiated with 106Ru/106Rh plaques between 1967 and 1977 were evaluated. They developed more exudative and hemorrhagic side effects after a short period of irradiation (1-6 days) than after a longer one (7-14 days). Spontaneous recovery of the radiation-induced retinal detachment was seen in all cases. Complete tumor regression with development of a flat scar was achieved with almost equal success with both short-term and protracted irradiation. To minimize radiogenic side effects the duration of irradiation recommended hitherto, i.e., 7-14 days, should be adhered to when treating malignant melanomas of the choroid with beta-ray applicators.
D000818:Animals; D001610:Beta Particles; D002830:Choroid Neoplasms / Q000532:radiotherapy*; D005123:Eye / Q000473:pathology / Q000528:radiation effects; D005500:Follow-Up Studies; D006801:Humans; D008545:Melanoma / Q000532:radiotherapy*; D009887:Ophthalmoscopy; D011817:Rabbits; D011833:Radiation Injuries, Experimental / Q000473:pathology; D011868:Radioisotopes / Q000627:therapeutic use; D011879:Radiotherapy Dosage; D012238:Rhodium / Q000627:therapeutic use; D012428:Ruthenium / Q000627:therapeutic use; D013997:Time Factors
D011868:Radioisotopes; D012428:Ruthenium; D012238:Rhodium
Ein Beitrag zur Optimierung der Bestrahlungszeit bei der Behandlung des malignen Melanoms der Aderhaut mit beta-Applikatoren (106Ru/106Rh).