Ru-106 Plaque Research Articles

Cerenkov Luminescence Imaging for Accurate Placement of Radioactive Plaques in Episcleral Brachytherapy of Intraocular Tumors.

The purpose of this study was to determine the feasibility of using Cerenkov luminescence imaging (CLI) to facilitate plaque placement during episcleral brachytherapy of intraocular tumors. Ruthenium-106 (Ru-106) decays to rhodium-106, which in turn emits high-energy beta particles. When the electrons propagate through the eyewall, the so-called Cerenkov effect leads to emission of weak light, which can be captured by high-sensitivity charge-couple device (CCD) cameras. Enucleated porcine eyes were prepared with tumor phantoms made of melanin-containing gelatin. The anterior portion of the globe was removed, and different Ru-106 plaque types (designated CCA, CCB, COB, and CIA) with activities ranging from 6.8 to 16.7 MBq were sutured to the sclera overlying the tumor phantom. The globe was placed in a transparent container with saline. CLI was performed through the anterior opening of the eye using a cooled electron-multiplying CCD camera. Exposure times between 5 and 60 seconds produced good quality images of the Cerenkov light. There was a linear relationship between plaque activity and Cerenkov radiance. The perimeters of the CCA and CCB plaques could be seen clearly as circles of light symmetrically surrounding the tumor phantoms. Notched COB and CIA plaques led to images revealing their actual positions in relation to the optic disc and ciliary body, respectively. Simulated plaque tilting resulted in diffuse demarcation of the light. The study indicates that CLI is a feasible method to ensure accurate placement of Ru-106 plaques in brachytherapy of intraocular tumors. CLI may offer a new tool to improve and document plaque placement, both perioperatively and postoperatively.

Multidimensional dosimetry of ¹⁰⁶Ru eye plaques using EBT3 films and its impact on treatment planning.

The purpose of this study was to establish a method to perform multidimensional radiochromic film measurements of (106)Ru plaques and to benchmark the resulting dose distributions against Monte Carlo simulations (MC), microdiamond, and diode measurements. Absolute dose rates and relative dose distributions in multiple planes were determined for three different plaque models (CCB, CCA, and COB), and three different plaques per model, using EBT3 films in an in-house developed polystyrene phantom and the mcnp6 MC code. Dose difference maps were generated to analyze interplaque variations for a specific type, and for comparing measurements against MC simulations. Furthermore, dose distributions were validated against values specified by the manufacturer (BEBIG) and microdiamond and diode measurements in a water scanning phantom. Radial profiles were assessed and used to estimate dosimetric margins for a given combination of representative tumor geometry and plaque size. Absolute dose rates at a reference depth of 2 mm on the central axis of the plaque show an agreement better than 5% (10%) when comparing film measurements (mcnp6) to the manufacturer's data. The reproducibility of depth-dose profile measurements was <7% (2 SD) for all investigated detectors and plaque types. Dose difference maps revealed minor interplaque deviations for a specific plaque type due to inhomogeneities of the active layer. The evaluation of dosimetric margins showed that for a majority of the investigated cases, the tumor was not completely covered by the 100% isodose prescribed to the tumor apex if the difference between geometrical plaque size and tumor base ≤4 mm. EBT3 film dosimetry in an in-house developed phantom was successfully used to characterize the dosimetric properties of different (106)Ru plaque models. The film measurements were validated against MC calculations and other experimental methods and showed a good agreement with data from BEBIG well within published tolerances. The dosimetric information as well as interplaque comparison can be used for comprehensive quality assurance and for considerations in the treatment planning of ophthalmic brachytherapy.

Secondary Enucleations for Uveal Melanoma: A 7-Year Retrospective Analysis

To describe the indications for secondary enucleations in uveal melanoma and analyze associations and outcomes. Retrospective interventional case series. Data of patients who underwent secondary enucleation for uveal melanoma in the London Ocular Oncology Service, between 2008 and 2014, were retrieved from medical records analyzed. Cox regression model was performed to analyze associations with secondary enucleation and metastases and Kaplan-Meier estimates to assess the probability of metastatic spread and death. During the study period 515 enucleations were performed for uveal melanoma, 99 (19%) of which were secondary enucleations. Tumors were located at the ciliary body in 21 eyes (21%), juxtapapillary in 31 (31%), and choroid elsewhere in 47 (48%). Primary treatment included Ru(106) plaque radiotherapy, proton beam radiotherapy, and transpupillary thermotherapy in 85, 11, and 3 eyes, respectively. Indications for secondary enucleation were tumor recurrence in 60 (61%), neovascular glaucoma in 21 (21%), and tumor nonresponse in 18 eyes (18%). Twenty patients (20%) were diagnosed with metastasis and 12 out of 20 died of metastatic spread. On multivariate analysis, juxtapapillary tumor location was found to associate with tumor nonresponse (P= .004) and nonresponding patients with metastatic spread (P= .04). Indications for secondary enucleations for uveal melanoma were tumor recurrence, neovascular glaucoma, and tumor nonresponse. This review identified a possible high-risk group (nonresponse), which proved radioresistant to treatment. These tumors were more frequently found in the juxtapapillary location and were associated with metastatic spread.

Outcomes of medium choroidal melanomas treated with ruthenium brachytherapy guided by three-dimensional pretreatment modeling.

The Collaborative Ocular Melanoma Study (COMS) established iodine-125 (I-125) plaque brachytherapy for eye preserving treatment of medium-sized choroidal melanomas in the United States. Eye Physics I-125 plaque treatment modeled with Plaque Simulator (PS) software yields similar results to COMS. Herein, we report results from a series of 15 patients treated with ruthenium-106 (Ru-106) plaque brachytherapy using PS pretreatment modeling for plaque localization and dosimetry. Fifteen patients with medium-sized choroidal melanomas (2.84-5.5mm in apical height and a basal diameter of 7.8-12.6mm) treated with ruthenium brachytherapy from 2003 to 2005 were evaluated retrospectively. Baseline and followup data were evaluated for tumor height, best corrected visual acuity, radiation retinopathy, radiation optic neuropathy, postradiation cataract formation, diplopia, and ptosis. Tumor response for both Ru-106 and I-125 plaques planned using the same PS pretreatment modeling was evaluated and compared. Isotope-specific radiation profiles were compared, and rates of local treatment failure (0%), optic neuropathy (6.7%), retinopathy (20%), and cataracts (33%) were evaluated. Five year-treated tumor heights were approximately 0.61 ± 0.29 (I-125, n= 16) and 0.53 ± 0.17 (Ru-106, n=6) of their heights at diagnosis. This patient subset had background characteristics very similar to those of the COMS and patients treated at our institution with I-125 plaques. Treatment response was equivalent although radiation complications occurred slightly less frequently in the Ru-106 group compared with those treated with I-125. Image-guided three-dimensional pretreatment modeling for plaque localization and dosimetry seems to work equally as well for Ru as for I-125 plaques and justifies more extensive investigation.

Plaque radiotherapy for anterior uveal melanomas

To determine the effectiveness of plaque radiation therapy for anterior uveal melanomas and to evaluate the risk and frequency of complications at different time intervals after the treatment. During 2010-2013 a total of 30 patients (10 male, 20 female) aged 11-73 (50 years on the average) with iris or iridociliary melanomas were treated with Ru-106 and Sr-90 ophthalmic plaques. In 8 patients the brachytherapy was preceded by local tumor excision. Morphological diagnosis was verified in 10 patients (8 iridectomies, 2 enucleations), of them 8 cases turned out to be spindle cell melanomas and the other 2--mixed cell melanomas. Follow-up period ranged from 1 to 54 months with the median of 13,5 months. Tumor regression was achieved in all cases. Enucleation had to be performed in 2 patients due to cornea and sclera necrosis. In the early post-brachytherapy period (up to 1 month) the most frequent radiation-related complications were keratopathy and uveitis (8 and 6 patients correspondingly). In patients observed for up to 3 months (28 patients) these were keratopathy and cataract (8 and 5 patients correspondingly). In the long-term (over 6 months) cataract predominated (17 patients). At the end of the study all patients were alive. Metastatic disease was diagnosed in one patient 30 months after the treatment. The results of the present clinical study confirm the effectiveness of brachytherapy for iris and iridociliary melanomas, which implies that tumor is well locally controlled and radiation-related complications are moderate and curable. This method of local tumor destruction can be another alternative to enucleation in cases when local tumor excision cannot be performed.

A choice of radionuclide: Comparative outcomes and toxicity of ruthenium-106 and iodine-125 in the definitive treatment of uveal melanoma

PurposeBoth iodine-125 (125I) Collaborative Ocular Melanoma Study and ruthenium-106 (106Ru) eye plaques can achieve excellent tumor control in patients diagnosed with uveal melanoma. We analyzed our single institutional experience in the management of ocular melanoma treated with either 125I or 106Ru plaque brachytherapy. Methods and materialsThe records of 107 patients with uveal melanoma treated with either 106Ru (n = 40) or 125I (n = 67) plaque brachytherapy between 2000 and 2008 were retrospectively reviewed. Tumor control parameters and toxicity were assessed. ResultsActuarial 5-year rates of local control, progression-free survival, and overall survival with 106Ru were 97%, 94%, and 92%, respectively. For 125I, these values were 83%, 65%, and 80%. In the subset of patients with tumor apex height ≤5 mm (36 125I and 40 106Ru), there was no difference in overall survival; however, progression-free survival was significantly improved with 106Ru (P = .02). Enucleation-free survival was significantly different between the 2 subsets, with no enucleations in the 106Ru cohort (P = .02). Patients treated with 106Ru experienced reduced retinopathy (P = .03) and cataracts (P < .01). ConclusionsBoth 125I and 106Ru eye plaque brachytherapy treatment result in encouraging tumor control for patients with uveal melanoma. We demonstrate that 106Ru offers these benefits with reduced toxicity in patients treated for uveal melanomas ≤5 mm in apical height.

Ruthenium-106 Plaque Brachytherapy for Uveal Melanoma: Factors Associated With Local Tumor Recurrence

Plaque brachytherapy is a common form of treatment for uveal melanoma, and the Collaborative Ocular Melanoma Study (COMS) employed I-125. Recently, Ru-106 has been reintroduced for plaque brachytherapy in the United States. We reviewed our experience treating uveal melanoma with Ru-106 plaque brachytherapy using COMS planning techniques, hypothesizing we would observe similar outcomes to those in the COMS.

Tumour regression pattern according to tumour shape after brachyther‐apy for 330 uveal melanomas

AbstractPurpose To describe regression patterns and their relationship with tumour shape of uveal melanoma by thickness and cross‐sectional area.Methods A retrospective study of 330 consecutive ciliochoroidal melanomas treated with I or Ru plaques in 2000‐2008 and imaged with Innovative Imaging I3‐ultrasound. Tumours were measured with Olympus DP‐Soft from original digital images. The COMS shape groups were partially collapsed: group 1: flat and crescent; group 2: oval and dome; group 3: mushroom; group 4: lobulated; and group 5: other or undetermined. Regression patterns were adapted from Abramson et al. (1990) into 4 main types: D (net decrease), S (stable), I (net increase), and M (for miscellaneous). We further subdivided M into 5 subtypes: DI (D&gt;I), DS (D&gt;S), ID (I&gt;D), SD (S&gt;D), and Z (zigzag; no trend).Results The regression pattern D was always the most common (31‐63% of tumors by thickness and 33‐72% by cross‐sectional area, for shape groups 1‐4); and the DS pattern was the second most common one (22‐24% and 16‐26%, respectively), except for group 2. Of the DI and Z patterns with later tumor increase, the former was fairly evenly spread across groups (5‐6% and 8‐10%, respectively) whereas the latter was observed mainly in shape groups 1 and 2 (15% and 17‐22%, respectively). The SD and ID patterns later tumor decrease were most common in shape groups 1 and 2, respectively, and most tumors representing the S pattern were shape group 1.Conclusion Heterogeneity in regression patterns and tumour shapes must be taken into account when using regression as a statistical variable in outcome analysis. Until now, all tumours have been pooled together despite significant differences in regression patterns, except in the study by Abramson et al. (1990).

(106)Ru plaque brachytherapy for uveal melanoma: factors associated with local tumor recurrence.

Plaque brachytherapy is a common form of treatment for uveal melanoma, and the Collaborative Ocular Melanoma Study (COMS) used (125)I. Recently, (106)Ru has been reintroduced for plaque brachytherapy in the United States. We reviewed our experience treating uveal melanoma with (106)Ru plaque brachytherapy using COMS planning techniques, hypothesizing that we would observe similar outcomes to those in the COMS. Medical records of patients undergoing (106)Ru plaque brachytherapy were reviewed retrospectively. Patient, tumor, and treatment characteristics were recorded. Outcomes including visual acuity, local tumor recurrence, salvage treatment, metastasis, and survival were recorded. Cox regression analyses were used to determine factors associated with local tumor recurrence and enucleation. Twenty-eight patients were studied. Median age was 60 years, and 50% were men. Median tumor base diameter and height were 9.4 and 2.6mm, respectively. Ophthalmic complications were rare. Local tumor recurrence and enucleation occurred in 13 and 4 patients, respectively. Local tumor recurrence was associated with low visual acuity in the tumor-bearing eye, posterior tumors, small plaque size, and difference in plaque-tumor diameter of <6mm. Enucleation was associated with low visual acuity and posteriorly located tumor. Estimated 5-year rate of death and metastasis was 18.5% and 11.4%, respectively. Among patients treated with (106)Ru plaque brachytherapy using COMS planning techniques, we found a greater than expected rate of local tumor recurrence. Planning (106)Ru plaque brachytherapy should be done carefully at centers that have previously used COMS protocols and (125)I.

Monte Carlo Simulation of the Treatment of Eye Tumors with 106Ru Plaques: A Study on Maximum Tumor Height and Eccentric Placement

Background/Aims: Ruthenium plaques are used for the treatment of ocular tumors. There is, however, a controversy regarding the maximum treatable tumor height. Some advocate eccentric plaque placement, without a posterior safety margin, to avoid collateral damage to the fovea and optic disc, but this has raised concerns about marginal tumor recurrence. There is a need for quantitative information on the spatial absorbed dose distribution in the tumor and adjacent tissues. We have overcome this obstacle using an approach based on Monte Carlo simulation of radiation transport. Methods: CCA and CCB ¹⁰⁶Ru plaques were modeled and their geometry embedded in a computerized tomography scan of the eye of a patient. Different tumor sizes and locations were simulated with the general-purpose Monte Carlo code PENELOPE. Results: Cumulative dose-volume histograms were obtained for the tumors and the tissues at risk considered. Plots of isodose lines for both plaques were obtained in a computerized tomography study. Conclusions: Ruthenium eye plaques are an adequate treatment option for tumors up to around 5 mm in height. According to our results, assuming a correct placement of the plaque, a tumor of 6.5 mm apical height is about the maximum size that can be treated safely with the large CCB plaque.

REGRESSION OF UVEAL MELANOMA AFTER RU-106 BRACHYTHERAPY AND THERMOTHERAPY BASED ON METABOLIC ACTIVITY MEASURED BY POSITRON EMISSION TOMOGRAPHY/COMPUTED TOMOGRAPHY

To evaluate regression rates of uveal melanoma after combined Ru-106 plaque radiotherapy and thermotherapy according to metabolic activity measured by positron emission tomography/computed tomography imaging. A retrospective medical chart review was conducted on 26 patients with uveal melanoma who underwent pretreatment whole-body positron emission tomography/computed tomography and received combined plaque radiotherapy and thermotherapy between 2006 and 2011. Tumors were classified as metabolically active and inactive based on the positron emission tomography/computed tomography imaging and compared with tumor height regression rates after treatment. Before treatment, the median tumor thickness was 8.8 mm for metabolically active tumors (7 eyes) and 5.0 mm for metabolically inactive tumors (19 eyes). The median tumor thicknesses with respect to the original thickness at 3, 6, and 12 months after treatment were 88%, 78%, and 64% for metabolically active tumors and 95%, 89%, and 81% for metabolically inactive tumors, respectively. The monthly tumor regression rates during the first 3 months (4.2% vs. 1.7%, P = 0.022) and the overall monthly tumor regression rates (3.0% vs. 1.5%, P = 0.041) were significantly higher for metabolically active tumors versus inactive tumors. Two patients with positive metabolic activity developed metastatic diseases 2 years after treatment, whereas no patient with negative metabolic activity developed metastatic disease during the study period. Positive metabolic activity of uveal melanoma based on the positron emission tomography/computed tomography was significantly associated with rapid initial tumor regression after combined plaque radiotherapy and thermotherapy, suggesting a prognostic value for this diagnostic approach.

Management of patients with uveal metastases at the Liverpool Ocular Oncology Centre

BackgroundUveal metastasis is the most common intraocular malignancy.MethodsThis was a retrospective study of all patients with uveal metastases referred to the Liverpool Ocular Oncology Centre between January 2007 and December...

Disease control and toxicity outcomes using ruthenium eye plaque brachytherapy in the treatment of uveal melanoma

PurposeRuthenium-106 (106Ru) eye plaques have the potential to achieve excellent tumor control with acceptable radiation toxicity. We evaluated our experience in the management of uveal melanoma treated with 106Ru brachytherapy. Methods and materialsThe records of 40 patients with uveal melanoma treated with brachytherapy using 106Ru plaques from 2003 to 2007 at University of Texas MD Anderson Cancer Center were reviewed. Endpoints assessed included tumor control and toxicity. ResultsMedian ophthalmologic follow-up was 67 months. Actuarial 5-year rates of local control (LC), progression-free survival (PFS), and overall survival (OS) were 97%, 94%, and 92%. There were 3 deaths, 2 related to melanoma. Fifteen patients experienced clinically significant visual loss; no patients were diagnosed with neovascular glaucoma, and 1 patient developed a clinically significant radiation-associated cataract. No patient required enucleation. ConclusionsWe report the largest published US cohort of patients treated with 106Ru plaque brachytherapy for uveal melanoma. Tumor control was excellent, and toxicity was acceptably low. These data support the reintroduction of 106Ru into clinical practice for ocular melanoma.

Disease Control and Toxicity Outcomes Comparing Ruthenium and Iodine Eye Plaque Brachytherapy in the Treatment of Intraocular Melanoma

Both Iodine-125 (125I) COMS and Ruthenium-106 (106Ru) eye plaques have the potential to achieve excellent tumor control in patients treated for uveal melanoma. We therefore evaluated our single institutional experience in the management of ocular melanoma treated with 125I and 106Ru plaque brachytherapy.

Metastasis inhibition after proton beam, β- and γ-irradiation of melanoma growing in the hamster eye.

Standard ocular tumor treatment includes brachytherapy, as well as proton therapy, particularly for large melanoma tumors. However, the effects of different radiation types on the metastatic spread is not clear. We aimed at comparing ruthenium ((106)Ru, emitting β electrons) and iodine ((125)I, γ-radiation) brachytherapy and proton beam therapy of melanoma implanted into the hamster eye on development of spontaneous lung metastases. Tumors of Bomirski Hamster Melanoma (BHM) implanted into the anterior chamber of the hamster eye grew aggressively and completely filled the anterior chamber within 8-10 days. Metastases, mainly in the lung, were found in 100% of untreated animals 30 days after enucleation. Tumors were irradiated at a dose of 3-10 Gy with a (106)Ru plaque and at a dose of 6-14 Gy using a (125)I plaque. The protons were accelerated using the AIC-144 isochronous cyclotron operating at 60 MeV. BHM tumors located in the anterior chamber of the eye were irradiated with 10 Gy, for the depth of 3.88 mm. All radiation types caused inhibition of tumor growth by about 10 days. An increase in the number of metastases was observed for 3 Gy of β-irradiation, whereas at 10 Gy an inhibition of metastasis was found. γ-radiation reduced the metastatic mass at all applied doses, and proton beam therapy at 10 Gy also inhibited the metastastic spread. These results are discussed in the context of recent clinical and molecular data on radiation effects on metastasis.

Accurate estimation of dose distributions inside an eye irradiated with 106Ru plaques

Irradiation of intraocular tumors requires dedicated techniques, such as brachytherapy with (106)Ru plaques. The currently available treatment planning system relies on the assumption that the eye is a homogeneous water sphere and on simplified radiation transport physics. However, accurate dose distributions and their assessment demand better models for both the eye and the physics. The Monte Carlo code PENELOPE, conveniently adapted to simulate the beta decay of (106)Ru over (106)Rh into (106)Pd, was used to simulate radiation transport based on a computerized tomography scan of a patient's eye. A detailed geometrical description of two plaques (models CCA and CCB) from the manufacturer BEBIG was embedded in the computerized tomography scan. The simulations were firstly validated by comparison with experimental results in a water phantom. Dose maps were computed for three plaque locations on the eyeball. From these maps, isodose curves and cumulative dose-volume histograms in the eye and for the structures at risk were assessed. For example, it was observed that a 4-mm anterior displacement with respect to a posterior placement of a CCA plaque for treating a posterior tumor would reduce from 40 to 0% the volume of the optic disc receiving more than 80Gy. Such a small difference in anatomical position leads to a change in the dose that is crucial for side effects, especially with respect to visual acuity. The radiation oncologist has to bring these large changes in absorbed dose in the structures at risk to the attention of the surgeon, especially when the plaque has to be positioned close to relevant tissues. The detailed geometry of an eye plaque in computerized and segmented tomography of a realistic patient phantom was simulated accurately. Dose-volume histograms for relevant anatomical structures of the eye and the orbit were obtained with unprecedented accuracy. This represents an important step toward an optimized brachytherapy treatment of ocular tumors.

Expression of 12 cytokines in aqueous humour of uveal melanoma before and after combined Ruthenium‐106 brachytherapy and transpupillary thermotherapy

To determine the aqueous humour levels of 12 cytokines in eyes with uveal melanoma and whether their expression changes after combined Ru-106 brachytherapy and transpupillary thermotherapy (TTT). Aqueous humour samples were collected from 20 patients with previously untreated uveal melanoma undergoing combined Ru-106 brachytherapy and TTT, both at the time of plaque placement and removal. Using multiplex biochip array technology, 12 different cytokines were measured, including interleukin (IL)-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, vascular endothelial growth factor (VEGF), tumour necrosis factor (TNF)-α, interferon (IFN)-γ, epidermal growth factor (EGF) and monocyte chemoattractant protein (MCP)-1. Aqueous humour from 20 patients undergoing cataract surgery was used as control. IL-6, IL-8, IFN-γ and MCP-1 were highly expressed in uveal melanoma, whereas IL-2, IL-10 and TNF- α were low in expression. There was a positive correlation between tumour height and IL-8 level (p = 0.020). Vascular endothelial growth factor tends to be highly expressed in melanoma-containing eyes (p = 0.056). Levels of IL-6, IL-8 and IL-1β increased after the mean 117 ± 38 hrs of brachytherapy and adjunctive TTT with a tumour apex dose of 61 ± 28 Gy and a scleral contact dose of 786 ± 226 Gy. Increase in levels of IL-6 (p = 0.003) and IL-8 (p = 0.046) positively correlated with scleral contact dose. Cytokines such as IL-6, IL-8, IFN-γ and MCP-1 may be implicated in the progression of uveal melanoma. Ocular irradiation from a Ru-106 plaque promoted an increase in the levels of IL-6, IL-8 and IL-1β, modulation of which could be useful in managing radiation-related side effects.

3D dosimetry on Ru-106 plaque for ocular melanoma treatments

Abstract For a few years at the Azienda Ospedaliero - Universitaria “Policlinico - Vittorio Emanuele” of Catania (Italy), ocular melanoma brachytherapic treatments with Ru-106 plaques have been made. This type of treatment is planned using the specific Treatment Planning System (TPS) BEBIG “Plaque Simulator” software that simulates the delivered dose distribution from the source used on the eye tissue. Improving dosimetry for ophthalmic therapeutic applications is worthwhile. Accurate dose measurements require detectors of adequate dimensions with respect to small distances involved. The main objective of the work is the improvement of dosimetry accuracy with a high sensitivity and spatial resolution system such as EBT2 Gafchromic ® film. The relative depth dose, the 2D and 3D distributions, the source uniformity and asymmetry were obtained using custom tissue equivalent phantom. Experimental results were compared with manufacturer’s calibration certificate data, TPS calculated values and Monte Carlo simulation results.

One-Day Session LINAC–Based Stereotactic Radiosurgery of Posterior Uveal Melanoma

LINAC-based stereotactic radiosurgery (SRS) of posterior uveal melanoma is a conservative method to treat uveal melanoma. This was a retrospective clinic-based study of patients with posterior uveal melanoma in stage T2/T3 who underwent 1-day session SRS at LINAC accelerator or SRS plus combined methods from 2001 to 2008. Thirty-nine patients with posterior uveal melanoma were treated with SRS (age 25-80 years, median 54 years). Median tumor volume at baseline was 0.6 cm3 (range 0.2-1.3 cm3). The therapeutic dose (TD) was 35.0 Gy, median of maximal dose applied was 49.0 Gy (range 37.0-60.0 Gy). Patient data were analyzed in groups: group 1, single SRS irradiation; group 2, SRS with subsequent endoresection or cyclectomy or additional transpupillary thermotherapy (TTT) or brachytherapy by Ru106 plaques; group 3a, enucleation after single SRS; group 3b, enucleation after SRS and endoresection/cyclectomy or TTT or brachytherapy Ru106. In patients with visual acuity of 20/40 or better, the median rate of best-corrected visual acuity (BCVA) decline was higher than that of the total and significantly higher than the rate of decline in the complementary group of patients with BCVA less than 20/40 (p=0.0077; Mann-Whitney U test). One-step LINAC-based SRS with a single dose 35.0 Gy is a method to treat middle-stage posterior uveal melanoma and to preserve the eye globe or as the first step of combined methods: irradiation before endoresection or cyclectomy.

Management of Retinoblastoma by 106Ru Plaque Therapy

Management of Retinoblastoma by 106Ru Plaque Therapy