Outcomes of choroidal melanomas treated with eye physics plaques: A 25-year review

Dose response relation for optic nerve atrophy at low-dose rate brachytherapy of uveal melanoma

BACKGROUND

Dose-response relationships for optic neuropathy and optic nerve atrophy after brachytherapy for posterior uveal melanoma were poorly defined from previous studies. Here, the outcome differences were analyzed in dependence on dosimetric factors, the applicator type, and tumor dependent variables.

PURPOSE

Primary objective was to evaluate the association of applied dose and on-set of optic nerve atrophy after brachytherapy for posterior uveal melanoma in order to allow risk estimation for new patients.

MATERIALS AND METHODS

This retrospective study was performed at a single high volume centre for ocular oncology. Patients receiving brachytherapy with Ruthenium-106 applicators for posterior uveal melanoma with a maximum distance between optic nerve and the nearest tumor margin of 4 optical disc diameters and follow-up with fundus photographs were included. The dose distribution at the optic nerve was reconstructed from the fundus photographs at latest follow-up and the dose-distribution of the applicator using a dedicated software. A first mask with important structural elements such as optic nerve, macula, tumor and vessels was first superimposed on the fundus photograph and adapted to the real contours. In a second step, an applicator contour mask was adapted to the radiation scar in order to calculate the dose distribution in all structures. Dose-response relations were obtained by weighted logistic regression.

RESULTS

The maximum dose at the optic disc (ODmax) in this group of 109 patients ranged from 5.8 Gy - 242.2 Gy, median 48.7 Gy. Optic nerve atrophy was observed in 29patients. Median time to radiation induced optic nerve atrophy was 18months. Using weighted logistic regression, the dependence of optic nerve atrophy on ODmax was significant (p = 0.0001, chi2-test). There was a considerable interobserver variability in ODmax values (p < 0.02, signed rank test). An additional factor influencing the dose-response was the applicator type (p = 0.0315, chi2-test). The ODmax for a probability of optic nerve atrophy of 50 % (ED50) were 77.6 Gy ± 7.0 Gy for patients treated with notched COB applicators and 53.2 Gy ± 8.2 Gy for patients with other applicators. Including the applicator type, the area under ROC curve reached a value of 0.857 (95 %-CI: 0.793-0.921) for the logistic model with ODmax. The ED50 for optic nerve neuropathy, classified as grade ≥ 1 toxicity, was estimated to be 46.9 Gy ± 4.1 Gy for the maximum dose at the optic disc.

CONCLUSIONS

Significant dose-response curves were found for optic nerve atrophy at low dose rate brachytherapy. A standard position of COB applicators was identified that allows estimation of the dose-response relation from the scleral dose of the applicator for risk estimation without fundus photographs. This larger data set enhances the knowledge of dose-response relationships for irradiation near the optic nerve.

3D-printed radiopaque episcleral plaques with radioactive collimating cavities for enhanced dose delivery in brachytherapy

PURPOSE

Episcleral plaque brachytherapy (EPBT) is a well-established treatment. However, the lateral dose to healthy tissues, such as the sclera, retina, and optic nerve is often problematic and results in side effects. This study proposes an innovative approach based on the 3D-printing of radiopaque polymer plaques featuring cylindrical radioactive cavities (CRC) with a potential collimating effect on radiation delivery to tumors.

METHODS AND MATERIALS

A CAD model based on the COMS protocol was created and 3D-printed using radiopaque PEEK polymer. Cylindrical cavities (1 mm depth/diameter) were evenly spaced on the plaque's inner surface. Two radioactive layouts (RL1: uniform loading; RL2: radial gradient loading) were designed. µCT imaging was used to assess the geometric accuracy of the 3D-printed CRC EPs, and dose distribution was evaluated for the two (2) radioactive layouts using MAGIC-pf gel dosimetry and T2-weighted MRI. The resulting dose profiles were compared with those generated by both COMS and SEP plaques.

RESULTS

Radiopaque CRC EPs showed higher central axis dose deposition while minimizing lateral overexposure compared to COMS and SEP plaques, while also providing robust back-shielding. Dose profiles from RL1 CRC EPs (uniform layout) extended deeper into the eye, whereas RL2 CRC EPs (with gradient) exhibited a more rapid dose fall-off, producing a concentrated, spherical dose distribution.

CONCLUSIONS

3D-printed radiopaque EPs with radioactivity encapsulated in cylindrical cavities demonstrated the ability to achieve more forward-projected dose profiles in EPBT. This fabrication design and a modulated radioactivity distribution across the EP surface would enable more precise and deeper dose delivery while reducing radiation exposure to lateral healthy tissues.

Functional outcome after Brachytherapy with bi-nuclide (Ru-106/Iodine-125) plaques in large uveal melanomas

OBJECTIVE

Preservation of visual acuity remains a challenging issue after globe sparing therapy of large uveal melanoma. The aim of our study was analyzing the functional outcome after brachytherapy with bi-nuclide plaques (BBNP), maintaining prognostic factors for legal blindness (LB).

METHODS

We have analyzed all consecutive patients with large uveal melanoma treated with BBNP at our institution between 01/1999 and 12/2020. The post-treatment follow-up data were screened up to 06/2023. Univariate and multivariate Cox regression analysis was performed to identify predictive factors for development of LB following BBNP.

RESULTS

Overall, 570 patients with median age of 65.6 years (interquartile range [IQR]: 54.5-74.0) underwent BBNP. During the median post-treatment follow-up of 30.8 months (IQR: 12.9-57.3), LB was diagnosed in 287 (50.4%) patients. Patients' age (> 67 years, adjusted hazard ratio [aHR] = 1.58, 95%-confidence interval [CI] = 1.24-2.00, p < 0.0001), tumor thickness (> 8.5 mm, aHR = 1.43, 95%-CI = 1.12-1.82, p = 0.004), VA (> 0.5 LogMAR, aHR = 1.59, 95%-CI = 1.25-2.02, p < 0.0001), and ciliary body involvement (aHR = 0.77, 95%-CI = 0.60-0.97, p = 0.029) were confirmed as independent predictors of LB in the final multivariable Cox regression analysis.

CONCLUSIONS

Approximately a half of patients with large uveal melanoma develop LB around 2.5 years after brachytherapy. Further optimization of treatment strategies, including both therapeutic and preventive measures, has the potential to enhance the functional outcome after episcleral plaque therapy for large UMs.

Re-treatment of locally recurrent uveal melanoma with repeat eye plaque I-125 brachytherapy: A single institution experience

PURPOSE

Eye plaque brachytherapy (EPBT) is the most common treatment for uveal melanoma with high local control rates of 95-100%. When local recurrences occur following EPBT, salvage options include enucleation, transpupillary thermotherapy (TTT), external beam radiation, or re-irradiation with EPBT. The purpose of this study is to report our institution's experience with EPBT re-irradiation for locally recurrent uveal melanoma.

METHODS AND MATERIALS

Patients were included if they were previously treated for uveal melanoma with EPBT, experienced local recurrence, and were subsequently treated at our institution with EPBT from 2016- 2020.

RESULTS

A total of 5 patients with median age 68 years were included. All patients were initially treated at an outside institution (OSI) with Iodine-125 or Ruthenium-106 EPBT. Mean time between EPBT at the OSI and EPBT at our facility was 130 months (range 28-231 months). Patients were re-irradiated with Iodine-125 EPBT prescribed to 85 Gy over 168 hours. Median follow up after re-treatment at our center was 24 months. Local control among this cohort was 100%. Metastasis occurred in two patients after re-treatment, at 8 months and 7 months. At last follow up, all treated lesions were decreased in size. Four patients experienced worsening visual acuity. Four patients developed cataracts, while two patients developed radiation retinopathy with cystoid macular edema requiring anti-VEGF injections. One patient developed radiation retinopathy but did not require injections. No patients required enucleation.

CONCLUSIONS

Re-treatment of locally recurrent uveal melanomas with EPBT is a feasible alternative to enucleation with a high local control rate. Ocular toxicities have not been significant enough to require enucleation.

Comparing efficacy of charged-particle therapy with brachytherapy in treatment of uveal melanoma

BACKGROUND

Uveal melanoma (UM) is the most common primary ocular tumour in adults. The most used eye-preserving treatments are charged-particle therapy (CPT) and brachytherapy. We performed a systematic review and meta-analysis to compare efficacies and complications of these two radiotherapies.

METHODS

We searched EMBASE, PubMed, MEDLINE, and the Cochrane Library from January 2012 to December 2022. Two independent reviewers identified controlled studies comparing outcomes of CPT versus brachytherapy. Case series that utilize either treatment modality were also reviewed.

RESULTS

One hundred fifty studies met the eligibility criteria, including 2 randomized control trials, 5 controlled cohort studies, and 143 case series studies. We found significant reduction in local recurrence rate among patients treated with CPT compared to brachytherapy (Odds ratio[OR] 0.38, 95% Confidence interval [CI] 0.24-0.60, p < 0.01). Analysis also showed a trend of increased risks of secondary glaucoma after CPT. No statistically significant differences were found in analyzing risks of mortality, enucleation, and cataract.

CONCLUSIONS

Our study suggested no difference in mortality, enucleation rate and cataract formation rate comparing the two treatments. Lower local recurrence rate and possibly higher secondary glaucoma incidence was noted among patients treated with CPT. Nevertheless, the overall level of evidence is limited, and further high-quality studies are necessary to provide a more definitive conclusion.

Tumor Shape-Specific Brachytherapy Implants by 3D-Printing, Precision Radioactivity Painting, and Biomedical Imaging

In brachytherapy (BT), or internal radiation therapy, cancer is treated by radioactive implants. For instance, episcleral plaques (EPs) for the treatment of uveal melanoma, are designed according to generic population approximations. However, more personalized implants can enhance treatment precision through better adjustment of dose profiles to the contours of cancerous tissues. An original approach integrating biomedical imaging, 3D printing, radioactivity painting, and biomedical imaging, is developed as a workflow for the development of tumor shape-specific BT implants. First, computer-aided design plans of EP are prepared according to guidelines prescribed by the Collaborative Ocular Melanoma Study protocol. Polyetheretherketone (PEEK), a high-performance polymer suitable for permanent implants, is used to 3D-print plaques and the geometrical accuracy of the printed design is evaluated by imaging. The possibility to modulate the dose distribution in a tridimensional manner is demonstrated by painting the inner surfaces of the EPs with radioactive 103Pd, followed by dose profile measurements. The possibility to modulate dose distributions generated by these 3D-printed plaques through radioactivity painting is therefore confirmed. Ex vivo surgical tests on human eyeballs are performed as an assessment of manipulation ease. Overall, this work provides a solution for the fabrication of tumor-specific radioactive implants requiring higher dose precision.

Radiotherapy in Uveal Melanoma: A Review of Ocular Complications

Uveal melanoma represents the most prevalent form of primary malignant intraocular tumor in adults. Historically, enucleation was considered the gold-standard approach in the treatment of uveal melanoma. Currently, radiotherapy is the most commonly used therapy, aiming at a better quality of life. However, radiotherapy can result in several ocular complications, some of which may be vision-threatening. Radiation-induced dry eye, scleral necrosis, cataract, rubeosis iridis, neovascular glaucoma, radiation retinopathy, maculopathy, and optic neuropathy are the most common complications. This article aims to summarize the current literature regarding the ocular complications after radiotherapy, as well as their clinical features, risk factors, and management strategies. A thorough understanding of these issues is crucial for ophthalmologists and oncologists to provide optimal patient care, improve visual outcomes, and minimize long-term complications.

Transitioning from a COMS-based plaque brachytherapy program to using eye physics plaques and plaque simulator treatment planning system: A single institutional experience

The aim of this work is to describe the implementation and commissioning of a plaque brachytherapy program using Eye Physics eye plaques and Plaque Simulator treatment planning system based on the experience of one institution with an established COMS-based plaque program. Although commissioning recommendations are available in official task groups publications such as TG-129 and TG-221, we found that there was a lack of published experiences with the specific details of such a transition and the practical application of the commissioning guidelines. The specific issues addressed in this paper include discussing the lack of FDA approval of the Eye Physics plaques and Plaque Simulator treatment planning system, the commissioning of the plaques and treatment planning system including considerations of the heterogeneity corrected calculations, and the implementation of a second check using an FDA-approved treatment planning system. We have also discussed the use of rental plaques, the analysis of plans using dose histograms, and the development of a quality management program. By sharing our experiences with the commissioning of this program this document will assist other institutions with the same task and act as a supplement to the recommendations in the recently published TG-221.

Dual-source strength seed loading for eye plaque brachytherapy using eye physics eye plaques: A feasibility study

Purpose

This study quantifies the dosimetric impact of incorporating two iodine-125 (¹²⁵I) seed source strengths in Eye Physics eye plaques for treatment of uveal melanoma.

Material and methods

Plaque Simulator was used to retrospectively plan 15 clinical cases of three types: (1) Shallow tumors (< 5.5 mm) with large base dimensions (range, 16-19 mm); (2) Tumors near the optic nerve planned with notched plaques; and (3) Very shallow (< 3.0 mm) tumors with moderate base dimensions (range, 13.5-15.5 mm) planned with larger plaques than requested by the ocular oncologist. Circular plaques were planned with outer ring sources twice the source strength of inner sources, and notched plaques with the six seeds closest to the notch at twice the source strength.

Results

In cases of type (1), the dual-source strength plan decreased prescription depth, and doses to critical structures were lower: inner sclera -25% ±2%, optic disc -7% ±3%, and fovea -6% ±3%. In four out of five cases of type (2), the dual-source strength plan decreased prescription depth, and dose to inner sclera was lower (-22% ±5%), while dose to optic disc (17% ±7%) and fovea (20% ±12%) increased. In cases of type (3), a smaller dual-source strength plaque was used, and scleral dose was lower (-45% ±3%), whereas dose to optic disc (1% ±14%) and fovea (5% ±5%) increased.

Conclusions

Dual-source strength loading as described in this study can be used to cover tumor margins and decrease dose to sclera, and therefore the adjacent retina, but can either decrease or increase radiation dose to optic disc and fovea depending on location and size of the tumor. This technique may allow the use of a smaller plaque, if requested by the ocular oncologist. Clinical determination to use this technique should be performed on an individual basis, and additional QA steps are required. Integrating the use of volumetric imaging may be warranted.

Predictive factors of radio-induced complications in 194 eyes undergoing gamma knife radiosurgery for uveal melanoma

BACKGROUND AND PURPOSE

To report the factors predictive of radio-induced complications (i.e. radiation retinopathy [RR], radiation papillopathy [RP] and neovascular glaucoma [NVG]) in uveal melanoma (UM) patients undergoing gamma knife radiosurgery (GKR).

MATERIALS AND METHODS

Longitudinal cohort study on patients with UM treated at the Ocular Oncology Service, San Raffaele Scientific Institute, Milan, between June 1994 and November 2018. Data were retrospectively reviewed. Rates of GKR-related complications were reported. Variables associated with each complication were investigated using multivariable Cox models and confirmed by logistic regression analysis. Hazard ratio (HR) and 95% confidence intervals (CI) were reported for significant associations.

RESULTS

One hundred ninety-four patients (99 males, 51%) were included, and 184 tumours were primarily located in the choroid (95%). Median follow-up was 57 months (range 6-286). Local control was achieved in 182 eyes (94%), and 152 eyes (78%) experienced at least one radiation-induced complication. Radiation retinopathy was documented in 67 eyes (35%) after a median of 23 months. Older age (HR = 0.97, 95% CI = 0.95-0.99, p = 0.02) had a protective effect for RR. Radiation papillopathy was diagnosed in 35 eyes (18%) after a median of 14 months after GKR. Macular or peripapillary location (HR = 3.06, 95% CI = 1.52-6.16, p = 0.002) was associated with increased risk of RP, while older age was protective (HR = 0.95, 95% CI = 0.93-0.98, p = 0.001). New-onset NVG was found in 53 eyes (27%), and median onset was 28 months. Tumour thickness (HR = 4.41, 95% CI = 2.23-8.72, p < 0.001) and peripapillary location (HR = 2.78, 95% CI = 1.46-5.27, p = 0.002) were the main risk factors associated with NVG.

CONCLUSION

Understanding factors predictive for radiation-related complications in patients undergoing GKR might help for better counselling and treatment planning.

Radiobiological evaluation of organs at risk for electronic high-dose-rate brachytherapy in uveal melanoma: a radiobiological modeling study

Purpose

The objective of this study was to examine feasibility of single- or hypo-fraction of high-dose-rate (HDR) electronic brachytherapy (eBT) in uveal melanoma treatment.

Material and methods

Biologically effective doses (BED) of organs at risk (OARs) were compared to those of iodine-125-based eye plaque low-dose-rate brachytherapy (¹²⁵I LDR-BT) with vitreous replacement (VR). Single- or hypo-fractionated equivalent physical doses (SFEDs or HFEDs) for tumor were calculated from tumor BED of ¹²⁵I LDR-BT using linear-quadratic (LQ) and universal survival curve (USC) models. BED OARs doses to retina opposite the implant, macula, optic disc, and lens were calculated and compared among SFED, HFED, and ¹²⁵I LDR-BT. Electronic BT of 50 kVp was considered assuming dose fall-off as clinically equivalent to ¹²⁵I LDR-BT. All OARs BEDs were analyzed with and without silicone oil VR.

Results

For a single-fraction incorporating VR, the median/interquartile range of LQ (USC)-based BED doses of the retina opposite the implant, macula, optic disc, and lens were 16%/1.2% (33%/4%), 35%/19.5% (64%/17.7%), 37%/19% (75%/17.8%), and 27%/7.9% (68%/23.2%) of those for ¹²⁵I LDR-BT, respectively. SFED tumor values were 29.8/0.2 Gy and 51.7/0.5 Gy when using LQ and USC models, respectively, which could be delivered within 1 hour. SFED can be delivered within 1 hour using a high-dose-rate eBT. Even four-fraction delivery of HFED without VR resulted in higher OARs doses in the macula, optic disc, and lens (135 ~ 159%) than when using ¹²⁵I LDR-BT technique. A maximum p-value of 0.005 was observed for these distributions.

Conclusions

The simulation of single-fraction eBT, including vitreous replacement, resulted in significantly reduced OARs doses (16 ~ 75%) of that achieved with ¹²⁵I LDR-BT.

Local tumor control and treatment related toxicity after plaque brachytherapy for uveal melanoma: A systematic review and a data pooled analysis

Uveal melanoma (UM) represents the most common primary intraocular tumor, and nowadays eye plaque brachytherapy (EPB) is the most frequently used visual acuity preservation treatment option for small to medium sized UMs. The excellent local tumor control (LTC) rate achieved by EPB may be associated with severe complications and adverse events. Several dosimetric and clinical risk factors for the development of EPB-related ocular morbidity can be identified. However, morbidity predictive models specifically developed for EPB are still scarce. PRISMA methodology was used for the present systematic review of articles indexed in PubMed in the last sixteen years on EPB treatment of UM which aims at determining the major factors affecting local tumor control and ocular morbidities. To our knowledge, for the first time in EPB field, local tumor control probability (TCP) and normal tissue complication probability (NTCP) modelling on pooled clinical outcomes were performed. The analyzed literature (103 studies including 21,263 UM patients) pointed out that Ru-106 EPB provided high local control outcomes while minimizing radiation induced complications. The use of treatment planning systems (TPS) was the most influencing factor for EPB outcomes such as metastasis occurrence, enucleation, and disease specific survival, irrespective of radioactive implant type. TCP and NTCP parameters were successfully extracted for 5-year LTC, cataract and optic neuropathy. In future studies, more consistent recordings of ocular morbidities along with accurate estimation of doses through routine use of TPS are needed to expand and improve the robustness of toxicity risk prediction in EPB.

Outpatient ocular brachytherapy: The USC Experience

Purpose

Ocular brachytherapy is a standard-of-care surgical procedure for globe salvage in the treatment of uveal melanoma. The procedure involves the placement and subsequent removal of a radioactive plaque several days later. At many locations, patients are admitted on an inpatient basis until plaque removal due to radiation safety concerns. However, patients may be discharged to home after plaque insertion, and subsequently return to the medical facility for plaque removal. This study aimed to evaluate the safety and systematic financial benefit of the outpatient ocular brachytherapy program at "?>the University of Southern California (USC) Roski Eye Institute for 30 years.

Methods and Materials

A single-institution retrospective record review was performed on all 275 patients who underwent brachytherapy for ocular tumors between January 1, 1989 and December 31, 2019 to assess for occurrences of reportable radiation and/or patients safety events. The treatment protocols at our institution are described. Data on hospital-adjusted expenses per inpatient day from the American Hospital Association's 2018 Annual Survey were used as a proxy for costs to patients and the health care system to perform a cost–benefit analysis comparing outpatient versus inpatient brachytherapy.

Results

Of the 275 plaque procedures over a 30-year period that were reviewed, there were no internally or externally reportable patient or radiation safety events. There were no adverse events related to patient transportation to the hospital, the patient not returning for plaque removal, operative issues in removing the plaque on time due to cancelled or delayed cases, or loss of radioactive material. Additionally, our cost–benefit analysis estimates that outpatient brachytherapy reduced costs for USC’s patients in 2018 by an average of $24,722 per patient treated with ocular brachytherapy.

Conclusions

With appropriate measures, outpatient ocular brachytherapy allows patients to safely return home with the added benefit of decreased financial burden for both patients and the broader health care system.

Recent advancements in the management of retinoblastoma and uveal melanoma

Retinoblastoma in children and uveal melanoma in adults can pose a serious threat to both vision and life. For many decades, enucleation was often the only option to treat these intraocular malignancies. For retinoblastoma, intra-arterial chemotherapy is often utilized as the primary treatment at advanced academic centers and has dramatically improved local tumor control and eye salvage rates. For uveal melanoma, both plaque brachytherapy and proton beam irradiation have served as widely utilized therapies with a local failure rate of approximately 1–10%, depending on the series. Major recent advancements have allowed for a better understanding of the genomics of uveal melanoma and the impact of certain mutations on metastatic susceptibility. Gene expression profile stratifies uveal melanomas into two classes: low-risk (class 1) and high-risk (class 2). A loss-of-function mutation of BAP1 is associated with a class 2 gene expression profile and therefore confers worse prognosis due to elevated risk of metastasis. On the other hand, gain-of-function mutations of EIF1AX and SF3B1 correspond to a gene expression profile of class 1A and class 1B and confer a better prognosis. Preferentially expressed antigen in melanoma (PRAME) is an antigen that increases metastatic susceptibility when expressed in uveal melanoma cells. In addition to plaque brachytherapy and proton beam irradiation, both of which have demonstrated superb clinical outcomes, scientists are actively investigating newer therapeutic modalities as either primary therapy or adjuvant treatment, including a novel nanoparticle therapy and immunotherapy.

Aflibercept for Radiation Maculopathy (ARM Study): Year-2 Extension of a Prospective Clinical Study

Purpose:

This work describes the 2-year results of the Aflibercept for Radiation Maculopathy (ARM) randomized clinical study that evaluated intravitreal vascular endothelial growth factor antagonist therapy in radiation maculopathy delivering aflibercept using a second-year collapsed, every-6-weeks, treat-and-adjust interval.

Methods:

Forty patients were enrolled in an institutional review board–approved clinical trial and randomly assigned to aflibercept treatment via 1 of 2 regimens: fixed, every-6-week treatment or variable, treat-and-adjust therapy centered around 6 weeks. All patients had a diagnosis of treated uveal melanoma with documented tumor control, and they had visually compromising radiation maculopathy. At conclusion of year 1, the first 30 patients were offered a collapsed single-arm variable of an every-6-weeks treat-and-adjust aflibercept injection schedule for an additional treatment year.

Results:

Baseline best-corrected visual acuity (BCVA) was 20/63 at ARM study entry 20/62 at the institution of the year-2 extension. At ARM study entry baseline, spectral domain–optical coherence tomography mean central retinal thickness was 432 µm and was 294 µm at the same institution. At the 2-year study’s conclusion, 76.7% (23 of 30) of eyes were better than 20/50, and only 6.7% (2 of 30) ended with a BCVA below 20/200. Final mean BCVA was 20/62 and final mean spectral domain–optical coherence tomography central retinal thickness was 286 µm, but as in year 1, this reduction in number of injections was not statistically significant.

Conclusions:

Aflibercept is effective in treating radiation maculopathy with maintained visual acuity at 2 years but continues to require an ongoing treatment approach to stabilize radiation maculopathy.

Iatrogenic Ocular Surface Diseases Occurring during and/or after Different Treatments for Ocular Tumours

Simple Summary

The ocular surface represents a finely regulated system that allows the protection of the eye. It can be affected by therapies used for the treatment of various intraocular tumours, particularly conjunctival cancers and uveal melanoma. In these conditions, treatments are chosen according to the characteristics of the lesion, and include a combination of selective surgery, anticancer eye drops, and/or radiotherapy delivered through different mechanisms. Possible side effects affecting the ocular surface range from transient dry eye or keratitis up to more severe complications such as corneal melting and perforation. These complications deserve careful evaluation for the risk of permanent sight-threatening sequelae. Physicians involved in the management of patients affected by ocular tumours should be aware of this risk in order to reach an early diagnosis and promptly set up an adequate treatment. The present review summarizes acute and chronic complications affecting the ocular surface following different therapies for the treatment of conjunctival cancers and uveal melanoma, and also reports clinical cases of representative patients who experienced these complications.

Abstract

The ocular surface represents a finely regulated system that allows the protection of the eye. It is particularly susceptible to different treatments for intraocular tumours, such as uveal melanoma and conjunctival cancers. Traditionally, the management of ocular tumours depends on the characteristics of the lesion, and is based on a combination of selective surgery, topical chemotherapy, and/or radiotherapy delivered through different mechanisms (e.g., charged-particle radiotherapy or brachytherapy). Possible complications involving the ocular surface range from transient dry eye disease or keratitis up to corneal melting and perforation, which in any case deserve careful evaluation for the risk of permanent sigh-threatening complications. Clinicians involved in the management of these patients must be aware of this risk, in order to reach an early diagnosis and promptly set up an adequate treatment. The present review of the literature will summarize acute and chronic complications affecting the ocular surface following different therapies for the treatment of ocular tumours.

Quantifying Subclinical and Longitudinal Microvascular Changes Following Episcleral Plaque Brachytherapy Using Spectral Domain-Optical Coherence Tomography Angiography

PURPOSE

To assess longitudinal microvascular changes in eyes treated with I-125 episcleral plaque brachytherapy (EPB).

METHODS

High resolution OCT angiograms of the central 3×3mm macula were obtained from I-125 episcleral plaque brachytherapy treated and untreated fellow eyes of 61 patients. Capillary density (vessel skeleton density, VSD) and caliber (vessel diameter index, VDI) were quantified using previously validated semi-automated algorithms. Nonperfusion was also quantified as flow impairment regions (FIR). Exams from treated and fellow eyes obtained pre-treatment and at 6-month, 1-year, and 2-year intervals were compared using generalized estimating equation linear models. Dosimetry maps were used to evaluate spatial correlation between radiation dose and microvascular metrics.

RESULTS

At 6 months, treated eyes had significantly lower VSD (0.145 ± 0.003 vs 0.155 ± 0.002; p = 0.009) and higher FIR (2.01 ± 0.199 vs 1.46 ± 0.104; p = 0.010) compared to fellow eyes. There was a significant decrease in VSD and a corresponding increase in FIR even for treated eyes without clinically identifiable retinopathy at 6 months. VDI was significantly higher in treated eyes than in fellow eyes at 2 years (2.92 ± 0.025 vs 2.84 ± 0.018; p < 0.001). When our cohort was categorized into low dose radiation (<15Gy) and high dose radiation (>45Gy) to the fovea, there were significant differences in VSD and FIR between groups.

CONCLUSIONS

OCTA can be used to quantify and monitor EPB induced retinopathy, and can detect vascular abnormalities even in the absence of clinically observable retinopathy. OCTA may therefore be useful in investigating treatment interventions that aim to delay EPB-induced radiation retinopathy.

106Ruthenium eye plaque brachytherapy in the management of medium sized uveal melanoma

Background

To evaluate ¹⁰⁶Ruthenium Brachytherapy in management of medium sized uveal melanoma, with emphasis on 5-year outcome and toxicity.

Methods

From April 2007 to October 2015, 39 patients with medium sized uveal melanoma were treated with 106 Ru eye plaques brachytherapy. At the time of diagnosis, the mean tumor depth was 3.7 mm (±SD:1.6 mm). The mean dose at the tumor apex was 141.4 Gy (± SD: 12.1 Gy) and 557.7 Gy (± SD: 257.3 Gy) to the sclera.

Results

Mean follow-up was 69.5 months (± SD: 53.8 months). Thirty-four patients (87.1%) remained free of recurrence. Twenty-six patients (66.7%) demonstrated a complete tumor regression after a median period of 12 months (3–60 mon.). By the final examination, the visual acuity of 26 patients (66.7%) was better than 20/200, and 12 patients (30.7%) had a visual acuity better than 20/40.

Retinopathy was detected in 11 patients (28.2%). After treatments only one patient (5.1%) had active vascular changes by the last examination. Moderate optic neuropathy was observed in 4 patients (10.3%). Cataract development was diagnosed in 21 patients (53.8%), and 16 patients (41%) had bilateral cataract development.

Special emphasis was made on patients with larger tumors. Twelve out of the 39 patients had a tumor with a depth of 5 mm or more. There was no significant difference in local control or in side effects between both groups observed.

Conclusions

Our study proved ¹⁰⁶Ru -brachytherapy to be an excellent treatment option with regard to tumor control and preservation of the visual acuity in well-selected patients. Our data suggested that this treatment is also suitable for tumors with a depth of more than 5 mm.

Blue-Light Fundus Autofluorescence Imaging following Ruthenium-106 Brachytherapy for Choroidal Melanoma

PURPOSE

To describe changes in blue-light fundus autofluorescence (FAF) and corresponding alterations in optical coherence tomography (OCT) within the irradiation field after ruthenium-106 brachytherapy (RBT) for choroidal melanoma.

METHODS

Consecutive patients with choroidal melanoma were included in a retrospective case series. Patients were treated with RBT at a single institution. As part of their routine examination patients underwent multimodal imaging including ultrasonography, fundus photography, OCT, and FAF imaging (excitation = 488 nm). FAF images were analysed for changes within the irradiation field.

RESULTS

31 patients (mean age 65.7 years) were treated with RBT for unilateral choroidal melanoma. Mean tumour height before therapy was 2.7 mm (SD 1.0). Mean follow-up time was 23.3 months (SD 13.3). Main FAF characteristics attributable to RBT emerged as increased FAF with speckled decreased FAF (FAF mottling) within the irradiation field and a rim of increased FAF at its border. OCT scans demonstrated loss of the ellipsoid zone and the external limiting membrane, thinning of the neurosensory retina, and alterations of the retinal pigment epithelium like clumping, migration, and atrophy.

CONCLUSIONS

FAF changes in the irradiation field after RBT of choroidal melanomas follow a characteristic pattern that correlates with distinct OCT alterations. FAF and OCT imaging give additional information to monitor effects of RBT and, therefore, complement multimodal imaging techniques after plaque therapy.

Nomogram for visual acuity outcome after iodine-125 plaque radiotherapy and prophylactic intravitreal bevacizumab for uveal melanoma in 1131 patients

AIMS

To develop a nomogram for prediction of visual acuity outcome following plaque radiotherapy for uveal melanoma.

METHODS

Retrospective review of uveal melanoma treated with plaque radiotherapy and prophylactic intravitreal bevacizumab injections at 4-month intervals for 2 years duration. Two nomograms for poor visual acuity outcome (Snellen <20/200) were developed based on (1) Clinical risk factors. (2) Or clinical and treatment risk factors.

RESULTS

There were 1131 included cases. The most important clinical risk factors (points for nomogram) for poor visual acuity outcome included subretinal fluid involving four quadrants (100), tumour thickness >4 mm (69), presenting visual acuity ≤20/30 (65), non-Caucasian race (58), tumour shape mushroom, bilobed, or multilobulated (57), and insulin-dependent diabetes (54). Risk of poor visual acuity at 2 years and 4 years increased from 11% and 24% with 40 points to 97% and >99% with 304 points. A second analysis was performed using both clinical and treatment risk factors. The most important factors included presenting visual acuity ≤20/30 (100), tumour largest basal diameter >11 mm (80), radiation dose rate to tumour base ≥164 cGy/hour (78), tumour thickness >4 mm (76), insulin-dependent diabetes (75) and abnormal foveolar status by optical coherence tomography at presentation (72). Risk of poor visual acuity at 2 years and 4 years increased from 6% and 14% with 56 points to 88% and 99% with 496 points.

CONCLUSIONS

A nomogram using clinical or treatment risk factors can predict visual acuity outcome following plaque radiotherapy and prophylactic intravitreal bevacizumab for uveal melanoma and is available online at https://fighteyecancer.com/nomograms/.

Aflibercept for Radiation Maculopathy Study: A Prospective, Randomized Clinical Study

PURPOSE

To evaluate 2 treatment approaches to intravitreal vascular endothelial growth factor antagonist therapy in radiation maculopathy comparing aflibercept delivered by either a 6-week treatment interval or treat-and-adjust interval.

DESIGN

Randomized, prospective clinical trial.

METHODS

Forty consecutive patients were enrolled in an institutional review board-approved clinical trial and randomized to aflibercept treatment via 1 of 2 regimens: (1) fixed, every-6-weeks treatment or (2) variable, treat-and-adjust treatment centered around 6 weeks. All patients had a diagnosis of treated uveal melanoma with documented tumor control. All patients showed visually compromising radiation maculopathy confirmed by a decline in best-corrected visual acuity (BCVA) and spectral-domain (SD) OCT documentation of radiation maculopathy.

MAIN OUTCOME MEASURES

Best-corrected visual acuity and SD OCT central retinal thickness at 1 year.

RESULTS

Thirty-nine of 40 patients completed the trial (97.5%) with 1 year of follow-up. Baseline study entry BCVA was 20/63 and was maintained at 20/62 at study conclusion at 60 weeks (1 year). At baseline, SD OCT mean central retinal thickness was 432 μm and improved to 294 μm at 60 weeks (P < 0.02). At the study conclusion, 42.5% of eyes (17/40) showed better than 20/50 BCVA, and only 5% of eyes (2/40) showed a BCVA worse than 20/200. In the every-6-weeks interval treatment arm, patients received 9 injections, whereas in the treat-and-adjust study arm, patients received 8.4 injections (P = 0.88, not significant). One patient experienced an inflammatory response after aflibercept injection, but this did not occur again for this patient, nor for any other study injections (1/400 injections [0.0025%]). No patients demonstrated endophthalmitis or metastatic disease or died during the study window.

CONCLUSIONS

Aflibercept seems to limit vision loss associated with radiation maculopathy. In this randomized, prospective clinical study, no difference was found between a fixed 6-week treatment interval and a variable treat-and-adjust interval because virtually all patients required treatment every 6 weeks and were not able to extend. Remarkably, almost half of all treated patients maintained BCVA of 20/50 or better throughout 1 year of treatment. Aflibercept is effective in treating radiation maculopathy, but requires an ongoing treatment approach.