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Purpose: The technical advancements now provide conservative treatment of choroidal melanoma. The course of the disease remains marked by the metastases that usually set in within 3 years. The aim of this paper is to report two unusual cases of hepatic metastases of choroidal melanoma that set in 11 and 18 Years after curietherapy., Methods: A 40-year-old woman and a 50-year-old man presented with T2 and T3 choroidal melanomas and were treated by cobalt plaque. The tumors decreased within the year and the patients were monitored every 3 months for 5 years., Results: Metastases set in, respectively, 11 and 18 years after treatment., Discussion and Conclusion: These two observations show that the metastases had already spread at the moment of diagnosis and that the cell doubling time of the melanoma was very long. These findings indicate the difficulties in monitoring patients with choroidal melanoma.

Human melanoma cells that are resistant to gamma rays were irradiated with 14 MeV neutrons given at low doses ranging from 5 cGy to 1.12 Gy at a very low dose rate of 0.8 mGy min(-1) or a moderate dose rate of 40 mGy min(-1). The biological effects of neutrons were studied by two different methods: a cell survival assay after a 14-day incubation and an analysis of chromosomal aberrations in metaphases collected 20 h after irradiation. Unusual features of the survival curve at very low dose rate were a marked increase in cell killing at 5 cGy followed by a plateau for survival from 10 to 32.5 cGy. The levels of induced chromosomal aberrations showed a similar increase for both dose rates at 7.5 cGy and the existence of a plateau at the very low dose rate from 15 to 30 cGy. The existence of a plateau suggests that a repair process after low-dose neutrons might be induced after a threshold dose of 5-7.5 cGy which compensates for induced damage from doses as high as 32.5 cGy. These findings may be of interest for understanding the relative biological effectiveness of neutrons and the effects of environmental low-dose irradiation.

Purpose: To analyze 65 patients with uveal melanomas treated with cobalt plaque therapy with regards to mortality, visual results and complications., Patients and Methods: Most of the melanomas were large (T3: 52.5%), with a mean largest dimension of the base of 11 mm, and a mean thickness of 6 mm. Most of the tumors were located in the choroid (95%), with an anterior margin behind the equator (65%), and a posterior margin at less than 3 mm of the disc and/or of the macula (69%). The plaque radiotherapy delivered a mean dose of 95 Gy to the tumor apex, either with a cobalt plaque alone (51 cases), or in association with a ruthenium plaque (14 cases). The mean follow up period was over 8 years., Results: The local control was achieved initially in 86% of the eyes. The estimated melanoma specific survival rate was 83% after 5 years and 74% after 10 years. The main parameter associated with the metastases was the largest dimension of the base (p < 0.01). The eye was retained in 83% of the cases. The probability of keeping a vision better than or equal to 0,1 was 39% after 5 years and 27% after 10 years. The main parameter associated with the visual loss was the tumor size (p < 0.01). The complications included cataract (39%), radiation retinopathy (34%), with maculopathy (19%) and/or papillopathy (13.5%), vitreous hemorrhages (22%), neovascular glaucoma (15%) and retinal detachment (12%)., Conclusion: These results supported the value of cobalt plaque radiotherapy in the management of uveal melanomas.

Fifty-seven uveal malignant melanomas (T2: 36.8%; T3: 49.1%) were treated between 1983 and 1989 with Cobalt 60 or/and Ruthenium 106 Rhodium 106 plaques. The mean follow-up was 32 months (from 6 to 69 months). A diminution of tumor size was observed in 88% of the cases, either rapid and marked (57%), or slower and more moderate (31%). A multivariate study showed the radiation dose administered to the tumor edge to be the most significant parameter associated with the tumor control. Seven patients developed metastases, and the probability of survival at 60 months was 83.3%. This probability was identical to that of 59 comparable patients treated, some years before, by enucleation. The most frequent complications were radiation retinopathy (28.1%) and retinal detachment (15.8%). The treated eye was retained in 86% of cases. In 57% of treated eyes, vision remained better or equal to 0.1. The predictive parameters of vision impairment after treatment seemed to be tumor size, tumor site near the macula and the optic nerve, and the radiation dose to the tumor base. The use of Ruthenium 106 Rhodium 106 appeared to be advantageous in controlling the disease as well as in reducing the incidence of complications.

The association 106Ru/106Rh and 60Co was used to treat choroidal malignant melanomas with a height of 7 mm above the scleral surface (4 cases) and tumors unsuccessfully treated with a first 60Co plaque therapy (3 cases). The association of both radionuclides allowed a dose of 85 Gy at the apex of the tumor and of 700 Gy at least on the base in every case. All the patients were alive without evidence of metastases with a minimum follow up of one year and the tumor regression was constant and sometimes spectacular.