Long-Term Followup Comparing Two Treatment Dosing Strategies of¹²⁵I Plaque Radiotherapy in the Management of Small/Medium Posterior Uveal Melanoma

Abstract

Objective. To investigate the efficacy of two different dosing strategies of radioactive iodine-125 (125I) in the management of small- and medium-sized posterior uveal melanoma. Patients and Methods. The medical records of consecutive patients with choroidal melanomas between 1.5 and 5.0 mm in apical height treated initially with 125I plaque radiotherapy were reviewed. Patients were treated with one of the following two treatment dosing strategies: (1) 85 Gy to the apical height of the tumor (group 1) or (2) 85 Gy to a prescription point of 5.0 mm (group 2). Results. Of 95 patients, 55 patients were treated to the apical height of the tumor, and 40 were treated to a prescription point of 5.0 mm. Comparative analysis of the incidence rates of specific complications between the two groups demonstrates that group 2 had a significantly higher incidence of radiation retinopathy, radiation optic neuropathy, and/or visually significant cataract formation than group 1 (P = 0.028). Conclusion. Treatment of choroidal melanomas less than 5 mm in apical height with 125I brachytherapy to the true apical height is equally effective when compared to treatment with 85 Gy to 5.0 mm. Treatment to the apical height of the tumor may result in lower incidence of radiation-related complications.

Iodine-125 Brachytherapy for Uveal Melanoma: A Systematic Review of Radiation Dose

“…Fourteen studies were retrospective clinical chart reviews [14,15,22,23,24,25,26,27,28,29,30,31,32], and 1 was a prospective, randomized trial, the COMS trial [17]. One retrospective study included patients from the COMS trial [15].…”

“…To our knowledge, there have been no prospective clinical trials comparing doses in the treatment of uveal melanoma. There have been a few single-institution retrospective studies suggesting that patients with tumors with an apical height of <5.0 mm benefit from lower doses of radiation [21,23,26]. Saconn et al [23] reported a series of 62 patients treated with a dose-reduced COMS design regimen with a mean prescription dose of 62.5 Gy to the tumor apex.…”

“…Their local control rate was comparable to the COMS trial (9 vs. 10.3%, respectively) with 73% of patients having a tumor height between 2.5 and 5.0 mm. In 2013, Murray et al [26] reported no significant differences in local control rates between patients treated with an adjusted dose to the apical height and those treated with the standard COMS design dose of 85.0 Gy to a depth of 5.0 mm. The latter study suggested that dose to the true apical height may render a lower incidence of radiation-related complications.…”

Gene Expression Profiling as an Adjunctive Measure to Guide the Management of Indeterminate, High-Risk Choroidal Melanocytic Lesions: A Pilot Study

“…Although the exact risks per case vary, the "average" patient's decision appeared to be based primarily on the knowledge of two key points: (1) they had a > 50% chance of demonstrating tumor growth if observed (based on having ≥3 clinical risk factors), and (2) their expected 5-year metastasis-free survival if observed until other events which would traditionally prompt treatment with plaque brachytherapy (such as definitive growth) occurred would be approximately 79% [33]. Of note, several series have documented excellent outcomes with treatment of small melanomas using palladium [34], iodine 125 [35], and ruthenium [36], even for posteriorly located lesions.…”

Efficacy and safety of dendrimer nanoparticles with coexpression of tumor necrosis factor-&alpha; and herpes simplex virus thymidine kinase in gene radiotherapy of the human uveal melanoma OCM-1 cell line

“…More recently, 125 I brachytherapy has gained acceptance as an effective treatment alternative for small and medium-sized melanomas. 39 However, simple radiotherapy can still injure the surrounding tissues, and some tumors even develop resistance to the radiation, resulting in reduction of therapeutic effect and its application. These are the primary factors to cause the failure of radiotherapy.…”