Ruthenium-106 brachytherapy for choroidal melanoma without transpupillary thermotherapy: Similar efficacy with improved visual outcome

Comparison of stereotactic radiotherapy and protons for uveal melanoma patients

Background and purpose

Uveal melanoma (UM) is the most common primary ocular malignancy. We compared fractionated stereotactic radiotherapy (SRT) with proton therapy, including toxicity risks for UM patients.

Materials and methods

For a total of 66 UM patients from a single center, SRT dose distributions were compared to protons using the same planning CT. Fourteen dose-volume parameters were compared in 2-Gy equivalent dose per fraction (EQD2). Four toxicity profiles were evaluated: maculopathy, optic-neuropathy, visual acuity impairment (Profile I); neovascular glaucoma (Profile II); radiation-induced retinopathy (Profile III); and dry-eye syndrome (Profile IV). For Profile III, retina Mercator maps were generated to visualize the geographical location of dose differences.

Results

In 9/66 cases, (14 %) proton plans were superior for all dose-volume parameters. Higher T stages benefited more from protons in Profile I, especially tumors located within 3 mm or less from the optic nerve. In Profile II, only 9/66 cases resulted in a better proton plan. In Profile III, better retina volume sparing was always achievable with protons, with a larger gain for T3 tumors. In Profile IV, protons always reduced the risk of toxicity with a median RBE-weighted EQD2 reduction of 15.3 Gy.

Conclusions

This study reports the first side-by-side imaging-based planning comparison between protons and SRT for UM patients. Globally, while protons appear almost always better regarding the risk of optic-neuropathy, retinopathy and dry-eye syndrome, for other toxicity like neovascular glaucoma, a plan comparison is warranted. Choice would depend on the prioritization of risks.

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.

Time Trends in the Treatment and Survival of 5036 Uveal Melanoma Patients in The Netherlands over a 30-Year Period

BACKGROUND

Uveal melanoma (UM) is a rare intraocular tumor with a dismal prognosis once metastasized. This study provides a nationwide overview and time trends of patients diagnosed with primary UM in the Netherlands between 1989 and 2019.

METHODS

A retrospective population-based cohort study based on patients with primary UM from the database of the Netherlands Cancer Registry (NCR), linked with the national population registry Statistics Netherlands on inhabitants' cause of death. Two time periods (1989-2004, 2005-2019) were compared with descriptive statistics. Kaplan-Meier and (multivariate) Cox proportional hazard models were used to assess changes over time for overall survival (OS) and cancer-specific survival (CSS).

RESULTS

In total, 5036 patients were analyzed with a median age of 64.0 years at the time of diagnosis. The number of patients increased over time. In the first (1989-2004) and second (2005-2019) period, 32% versus 54% of the patients received radiotherapy (p < 0.001). The median FU time was 13.4 years. The median OS of the first and second periods was 9.5 (95% CI 8.7-10.3) versus 11.3 years (95% CI 10.3-12.3; p < 0.001). The median CSS was 30.0 years (95% CI NA) in the first period and not reached in the second period (p = 0.008). In multivariate analysis (MVA), female gender (HR 0.85; 95% CI 0.79-0.92, p < 0.001) and radiotherapy treatment (HR 0.73; 95% CI 0.64-0.83, p < 0.001) were associated with better OS. Radiotherapy treatment (HR 0.74; 95% CI 0.61-0.90, p = 0.002) was also associated with better CSS. The period of diagnosis was not associated with OS or CSS.

CONCLUSIONS

In this study of patients with primary UM, there was a shift to the diagnosis of smaller tumors, possibly due to stage migration. There was also an increase in eye-preserving treatments over time. OS and CSS were modestly improved in the second time period; however, the time period was not associated with OS or CSS in multivariate analyses.

MR-based follow-up after brachytherapy and proton beam therapy in uveal melanoma

PURPOSE

MRI is increasingly used in the diagnosis and therapy planning of uveal melanoma (UM). In this prospective cohort study, we assessed the radiological characteristics, in terms of anatomical and functional imaging, of UM after ruthenium-106 plaque brachytherapy or proton beam therapy (PBT) and compared them to conventional ultrasound.

METHODS

Twenty-six UM patients were evaluated before and 3, 6 and 12 months after brachytherapy (n = 13) or PBT (n = 13). Tumour prominences were compared between ultrasound and MRI. On diffusion-weighted imaging, the apparent diffusion value (ADC), and on perfusion-weighted imaging (PWI), the time-intensity curves (TIC), relative peak intensity and outflow percentages were determined. Values were compared between treatments and with baseline.

RESULTS

Pre-treatment prominences were comparable between MRI and ultrasound (mean absolute difference 0.51 mm, p = 0.46), but larger differences were observed post-treatment (e.g. 3 months: 0.9 mm (p = 0.02)). Pre-treatment PWI metrics were comparable between treatment groups. After treatment, brachytherapy patients showed favourable changes on PWI (e.g. 67% outflow reduction at 3 months, p < 0.01). After PBT, significant perfusion changes were observed at a later timepoint (e.g. 38% outflow reduction at 6 months, p = 0.01). No consistent ADC changes were observed after either treatment, e.g. a 0.11 × 10^-3mm²/s increase 12 months after treatment (p = 0.15).

CONCLUSION

MR-based follow-up is valuable for PBT-treated patients as favourable perfusion changes, including a reduction in outflow, can be detected before a reduction in size is apparent on ultrasound. For brachytherapy, a follow-up MRI is of less value as already 3 months post-treatment a significant size reduction can be measured on ultrasound.

Comparison of Magnetic Resonance Imaging-Based and Conventional Measurements for Proton Beam Therapy of Uveal Melanoma

OBJECTIVE

Conventionally, ocular proton therapy (PT) is planned using measurements obtained by an ophthalmologist using ultrasound, fundoscopy, biometry, and intraoperative assessments. Owing to the recent advances in magnetic resonance imaging (MRI) of uveal melanoma (UM), it is possible to acquire high-resolution 3-dimensional images of the eye, providing the opportunity to incorporate MRI in ocular PT planning. In this study, we described how these measurements can be obtained using MRI, compared the MRI-based measurements with conventional ophthalmic measurements, and identified potential pitfalls for both modalities.

DESIGN

Cross-sectional study.

SUBJECTS

Data from 23 consecutive patients with UM treated with PT were retrospectively evaluated.

METHODS

Magnetic resonance imaging-based measurements of axial length, tumor height and basal diameter, and marker-tumor distances were compared with the conventional ophthalmic measurements, and discrepancies were evaluated in a multidisciplinary setting.

MAIN OUTCOME MEASURES

Tumor prominence and basal diameters on MRI and ultrasound, axial length on MRI and biometry, tumor-marker distances on MRI and measured intraoperatively.

RESULTS

The mean absolute differences of the tumor height and basal diameter measurements between ultrasound and MRI were 0.57 mm and 1.44 mm, respectively. Larger absolute differences in height and basal diameter were observed when the full tumor extent was not visible on ultrasound (0.92 mm and 1.67 mm, respectively) compared with when the full tumor extent was visible (0.44 mm and 1.15 mm, respectively). When the full tumor was not visible on ultrasound, MRI was considered more reliable. Tumor-marker distances measured using MRI and intraoperative techniques differed < 1 mm in 55% of the markers. For anteriorly located and mushroom-shaped tumors (25% of the markers), MRI provided more accurate measurements. In flat UM (15% of the markers), however, it was difficult to delineate the tumor on MRI. The mean absolute difference in axial length between optical biometry and MRI was 0.50 mm. The presence of the tumor was found to influence optical biometry in 15 of 22 patients; the remaining patients showed a better agreement (0.30 mm). Magnetic resonance imaging-based biometry was considered more reliable in patients with UM.

CONCLUSIONS

Magnetic resonance imaging allowed for the 3-dimensional assessment of the tumor and surrounding tissue. In specific patients, it provided a more reliable measurement of axial length, tumor dimensions, and marker-tumor distances and could contribute to a more accurate treatment planning. Nevertheless, a combined evaluation remains advised, especially for flat UM.

Predictive Parameters in Patients Undergoing Percutaneous Hepatic Perfusion with Melphalan for Unresectable Liver Metastases from Uveal Melanoma: A Retrospective Pooled Analysis

Purpose

The aim of this study was to identify positive predictors for survival in uveal melanoma (UM) patients treated with percutaneous hepatic perfusion with melphalan (M-PHP), by retrospectively pooling data from three centers.

Materials and Methods

Retrospective analysis including patients (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge$$\end{document}≥ 18 years) treated with M-PHP between February 2014 and December 2019 for unresectable liver-dominant or liver-only metastases from UM. Predictors for OS were assessed using uni- and multivariate analyses. Other study outcome measures were response rate, progression-free survival (PFS), liver progression-free survival (LPFS), overall survival (OS) and complications according to CTCAEv5.0.

Results

In total, 101 patients (47.5% males; median age 59.0 years) completed a minimum of one M-PHP. At a median follow-up time of 15.0 months, complete response (CR), partial response (PR), stable disease (SD) and progressive disease were seen in five (5.0%), 55 (54.5%), 30 (29.7%) and 11 (10.9%) patients, respectively, leading to a 89.1% disease control rate. Median PFS, LPFS and OS were 9.0, 11.0 and 20.0 months, respectively. Survival analyses stratified for radiological response demonstrated significant improved survival in patients with CR or PR and SD category. Treatment of the primary tumor with radiotherapy, ≥ 2 M-PHP and lactate dehydrogenase (LDH) < 248 U/L were correlated with improved OS. Thirty-day mortality was 1.1% (n = 2). Most common complication was hematological toxicity (self-limiting in most cases).

Conclusion

M-PHP is safe and effective in patients with UM liver metastases. Achieving CR, PR or SD is associated with improved survival. Primary tumor treatment with radiotherapy, normal baseline LDH and > 1 M-PHP cycles are associated with improved OS.

Prognostic Biomarkers in Uveal Melanoma: The Status Quo, Recent Advances and Future Directions

Simple Summary

Although rare, uveal melanoma (UM) is the most common cancer that develops inside adult eyes. The prognosis is poor, since 50% of patients will develop lethal metastases in the first decade, especially to the liver. Once metastases are detected, life expectancy is limited, given that the available treatments are mostly unsuccessful. Thus, there is a need to find methods that can accurately predict UM prognosis and also effective therapeutic strategies to treat this cancer. In this manuscript, we initially compile the current knowledge on epidemiological, clinical, pathological and molecular features of UM. Then, we cover the most relevant prognostic factors currently used for the evaluation and follow-up of UM patients. Afterwards, we highlight emerging molecular markers in UM published over the last three years. Finally, we discuss the problems preventing meaningful advances in the treatment and prognostication of UM patients, as well as forecast new roadblocks and paths of UM-related research.

Abstract

Uveal melanoma (UM) is the most common malignant intraocular tumour in the adult population. It is a rare cancer with an incidence of nearly five cases per million inhabitants per year, which develops from the uncontrolled proliferation of melanocytes in the choroid (≈90%), ciliary body (≈6%) or iris (≈4%). Patients initially present either with symptoms like blurred vision or photopsia, or without symptoms, with the tumour being detected in routine eye exams. Over the course of the disease, metastases, which are initially dormant, develop in nearly 50% of patients, preferentially in the liver. Despite decades of intensive research, the only approach proven to mildly control disease spread are early treatments directed to ablate liver metastases, such as surgical excision or chemoembolization. However, most patients have a limited life expectancy once metastases are detected, since there are limited therapeutic approaches for the metastatic disease, including immunotherapy, which unlike in cutaneous melanoma, has been mostly ineffective for UM patients. Therefore, in order to offer the best care possible to these patients, there is an urgent need to find robust models that can accurately predict the prognosis of UM, as well as therapeutic strategies that effectively block and/or limit the spread of the metastatic disease. Here, we initially summarized the current knowledge about UM by compiling the most relevant epidemiological, clinical, pathological and molecular data. Then, we revisited the most important prognostic factors currently used for the evaluation and follow-up of primary UM cases. Afterwards, we addressed emerging prognostic biomarkers in UM, by comprehensively reviewing gene signatures, immunohistochemistry-based markers and proteomic markers resulting from research studies conducted over the past three years. Finally, we discussed the current hurdles in the field and anticipated the future challenges and novel avenues of research in UM.

Clinical Outcomes after International Referral of Uveal Melanoma Patients for Proton Therapy

Simple Summary

This study aims to assess cancer control and preservation of the eye and visual acuity after proton therapy abroad for eye melanoma. For this, medical files were reviewed of Dutch uveal melanoma patients who were treated in Switzerland with proton therapy from 1987 to 2019. The tumours of these patients were too large and/or localised too close to the optic nerve to be treated with local plaque irradiation. There were 103 patients, of whom one had a uveal melanoma in both eyes. The tumours were relatively large and often localised around the central part of the retina. At five years after treatment, proton therapy had controlled the uveal melanomas of 94% of the patients and 81% had preserved their eye. Spread of the cancer beyond the eye was observed in 30% of the patients. Most patients (79%) became blind or had severe visual impairment after proton therapy; a small group of patients had mild or no visual impairment (17%). The size of the tumour, its localisation and the dose of proton therapy were important for the risk of decline in visual acuity. This study shows that proton therapy abroad for uveal melanoma is feasible and yields good results.

Abstract

Objective: To assess oncological and ophthalmological outcomes after international referral of uveal melanoma patients for proton therapy. Materials and Methods: This is a retrospective study among Dutch uveal melanoma patients who were treated in Switzerland with 60.0 CGE proton therapy (in 4 fractions) from 1987 to 2019. All patients were ineligible for brachytherapy due to tumour size and/or proximity to the optic nerve. Time-to-event analyses were performed using Kaplan–Meier’s methodology and Cox proportional hazards models. Results: There were 103 patients (104 eyes) with a median largest tumour diameter of 19 mm (range 6–26 mm). Tumours were localised centrally (11%), mid-peripherally (65%) or peripherally (34%). Median follow-up was 7 years. Five-year local control, distant metastasis-free survival and eye preservation rates were 94%, 70% and 81% respectively. At five years, severe, moderate and mild visual impairment was observed in respectively 79%, 4% and 6% of the patients. Larger tumour volumes and more central tumour localisation were associated with severe visual impairment. After correction for these factors, dose to the macula, optic disc and retina, but not optic nerve was significantly associated with severe visual impairment. Conclusion: International referral for proton therapy yielded good tumour control and eye preservation rates, but risk of distant metastasis and severe visual impairment were substantial, possibly due to the selection of advanced tumour stages and/or central localisation. Dose to the macula may be more relevant than dose to the optic nerve for preservation of visual acuity, which is relevant for the treatment planning of proton therapy.

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.

An Automatic Framework to Create Patient-specific Eye Models From 3D Magnetic Resonance Images for Treatment Selection in Patients With Uveal Melanoma

PURPOSE

The optimal treatment strategy for uveal melanoma (UM) relies on many factors, the most important being tumor size and location. Building on recent developments in high-resolution 3D ocular magnetic resonance imaging (MRI), we developed an automatic image-processing framework to create patient-specific eye models and to subsequently determine the full 3D tumor shape and size automatically.

METHODS AND MATERIALS

From 15 patients with UM, 3D inversion-recovery gradient-echo (T1-weighted) and 3D fat-suppressed spin-echo (T2-weighted) images were acquired with a 7T MRI scanner. First, the sclera and cornea were segmented from the T2-weighted image by mesh-fitting. The T1- and T2-weighted images were then coregistered. From the registered T1-weighted image, the lens, vitreous body, retinal detachment, and tumor were segmented. Fuzzy C-means clustering was used to differentiate the tumor from retinal detachments. The tumor model was verified and (if needed) edited by an ophthalmic MRI specialist. Subsequently, the prominence and largest basal diameter of the tumor were measured automatically based on the verified contours. These results were compared with manual assessments on the original images and with ultrasound measurements to show the errors in manual analysis.

RESULTS

The framework successfully created an eye model fully automatically in 12 cases. In these cases, a Dice similarity coefficient (mean surface distance) of 97.7%±0.84% (0.17±0.11 mm) was achieved for the sclera, 96.8%±1.05% (0.20±0.06 mm) for the vitreous body, 91.6%±4.83% (0.15±0.06 mm) for the lens, and 86.0%±7.4% (0.35±0.27 mm) for the tumor. The manual assessments deviated, on average, 0.39±0.31 mm in prominence and 1.7±1.22 mm in basal diameter from the automatic measurements.

CONCLUSIONS

The described framework combined information from T1- and T2-weighted images to accurately determine tumor boundaries in 3D. The proposed process may have a direct effect on clinical workflow, as it enables an accurate 3D assessment of tumor dimensions, which directly influences therapy selection.

Diagnostic methods and therapeutic options of uveal melanoma with emphasis on MR imaging-Part II: treatment indications and complications

Therapy of uveal melanoma aims to preserve the eye and its function and to avoid metastatic dissemination. The treatment choice is difficult and must keep into account several factors; the therapeutic strategy of uveal melanoma should therefore be personalized, sometimes requiring to combine different treatment techniques. Nowadays globe-sparing radiotherapy techniques are often preferred to enucleation. Plaque brachytherapy, the most commonly used eye-preserving therapy, is suitable for small- and medium-sized uveal melanomas. Proton beam radiotherapy is indicated for tumours with noticeable size, challenging shape and location, but is more expensive and less available than brachytherapy. Enucleation is currently restricted to advanced tumours, uveal melanomas with orbital or optic nerve involvement, blind and painful eyes because of treatment-related complications (neovascular glaucoma, chronic inflammatory processes). The effect of proton beam therapy on neoplastic tissue is related to direct cytotoxic action of the radiations, impairment of neoplastic vascular supply and immunologic response. Complications after radiotherapy are frequent and numerous and mainly related to tumour thickness, radiation dose and distance between the tumour and optic nerve. The purpose of this pictorial review is to provide the radiologists with awareness about diagnostic methods and therapeutic options of uveal melanoma. In the present second section, we discuss the therapeutic management of uveal melanoma, describing the main ocular-conserving radiotherapic techniques. We subsequently present an overview of the effects of radiations on neoplastic tissue. Lastly, we review ocular complications following radiotherapy that should be evaluated by radiologists during follow-up MRI examinations.

Extracutaneous Melanoma

Extracutaneous melanomas (ECMs) represent a heterogeneous group of melanoma subtypes characterized by distinct clinical and biological features from cutaneous melanoma. These subtypes share an aggressive natural history with high mortalities compared with nonacral cutaneous melanoma (NACM). Although recent advances in NACM have made significant improvements in morbidity and mortality, ECMs continue to lag behind. As the pathogenesis and molecular features of these rare subtypes continue to emerge, therapeutic research has aimed to closing the gap.

Current molecular and clinical insights into uveal melanoma (Review)

Uveal melanoma (UM) represents the most prominent primary eye cancer in adults. With an incidence of approximately 5 cases per million individuals annually in the United States, UM could be considered a relatively rare cancer. The 90-95% of UM cases arise from the choroid. Diagnosis is based mainly on a clinical examination and ancillary tests, with ocular ultrasonography being of greatest value. Differential diagnosis can prove challenging in the case of indeterminate choroidal lesions and, sometimes, monitoring for documented growth may be the proper approach. Fine needle aspiration biopsy tends to be performed with a prognostic purpose, often in combination with radiotherapy. Gene expression profiling has allowed for the grading of UMs into two classes, which feature different metastatic risks. Patients with UM require a specialized multidisciplinary management. Primary tumor treatment can be either enucleation or globe preserving. Usually, enucleation is reserved for larger tumors, while radiotherapy is preferred for small/medium melanomas. The prognosis is unfavorable due to the high mortality rate and high tendency to metastasize. Following the development of metastatic disease, the mortality rate increases to 80% within one year, due to both the absence of an effective treatment and the aggressiveness of the condition. Novel molecular studies have allowed for a better understanding of the genetic and epigenetic mechanisms involved in UM biological activity, which differs compared to skin melanomas. The most commonly mutated genes are GNAQ, GNA11 and BAP1. Research in this field could help to identify effective diagnostic and prognostic biomarkers, as well as novel therapeutic targets.

The Economic Value of MR-Imaging for Uveal Melanoma

Objective

Uveal melanoma (UM) is the most common primary intra-ocular tumour. Treatment is determined by tumour size and location. Generally, smaller tumours are eligible for brachytherapy unless they are located close to posterior pole. Larger tumours are enucleated or undergo proton beam therapy (PBT), which is more expensive than brachytherapy and less available. Accuracy of tumour size determination is critical for accurate planning and delivery of treatment, particularly to ensure tumour coverage, critical structure sparing, and for the choice of treatment modality. This is particularly the case for tumour dimensions that are close to the cut-off point for a specific type of treatment: in the case of the brachytherapy protocol at our institution, 6-8 mm. Ultrasound is conventionally used, but magnetic resonance imaging (MRI) has recently become an additional available tool. Although more expensive, it enables more accurate measurements and is particularly useful in combination with clinical fundus examination, fundus photography and ultrasound. Our aim in this paper was to determine the economic value of MRI for UM treatment.

Methods

We retrospectively analysed 60 patients' MRI scans acquired as part of a study or for clinical care. For each patient, we assessed whether the extra cost of an MRI generated economic benefit or change in optimal treatment.

Results

MRI indicated a smaller tumour prominence than US in 10% of patients with intermediate tumour size, resulting in a change from PBT to brachytherapy. The costs of MRI, €200-€1000, are significantly lower than the higher costs of PBT compared to brachytherapy, €24,000 difference. In addition, the annual total economic burden of severe vision impairment associated with eye removal is €10,000. Furthermore, for patients where ultrasound was impossible due to previous surgery, MRI enabled eye-preserving treatment.

Conclusion

An additional MRI for specific patients with UM improves economic value as it enables less expensive treatment in a sufficient percentage of patients to compensate for the MRI costs. Value is increased in terms of quality of care as it enables for some a treatment option which spares more vision.

Management of conjunctival melanoma with local excision and adjuvant brachytherapy

BACKGROUND/OBJECTIVES

To evaluate the management of conjunctival melanoma with local excision and adjuvant brachytherapy.

SUBJECTS/METHODS

Data of all patients who received local excision and adjuvant brachytherapy for conjunctival melanoma between 1999 and 2016 in a Dutch national referral centre were reviewed. A protocol with Sr-90 was used until 2012, a protocol with Ru-106 was used hereafter. Local recurrence, metastasis, survival, visual acuity and treatment complications were assessed.

RESULTS

A total of 58 patients was identified: 32 patients were treated with Sr-90 and 26 with Ru-106. Mean follow-up time was 97.3 months (143.1 months after Sr-90, and 40.2 months after Ru-106). All lesions were epibulbar, the median tumour thickness was 0.9 mm. Local recurrence occurred in 13/58 cases (22%), with a 5-year recurrence rate of 21%. Local recurrence occurred equally often in both protocols, with 5-year recurrence rates of 19% (Sr-90) versus 23% (Ru-106) (p = 0.68). Metastasis developed in 3/58 cases (5%), with 2 cases after Sr-90, and 1 after Ru-106 (p = 1.00). The most reported complications were pain (29%), dry eyes (21%), symblepharon (9%), ptosis (12%) and cataract (9%). No severe corneal or scleral complications were observed. Median visual acuity was 1.00 pre-surgery, at the end of follow-up this was 1.00 (Sr-90) and 0.95 (Ru-106).

CONCLUSION

Local excision with adjuvant brachytherapy provides good tumour control with excellent visual outcome and mild side effects in patients with limited conjunctival melanoma. Results after Sr-90 or Ru-106 were comparable; a choice for either treatment may be based on experience of the clinician and availability of materials.

Uveal melanoma

Uveal melanoma (UM) is the most common primary intraocular malignancy in adults. UMs are usually initiated by a mutation in GNAQ or GNA11, unlike cutaneous melanomas, which usually harbour a BRAF or NRAS mutation. The annual incidence in Europe and the USA is ~6 per million population per year. Risk factors include fair skin, light-coloured eyes, congenital ocular melanocytosis, ocular melanocytoma and the BAP1-tumour predisposition syndrome. Ocular treatment aims at preserving the eye and useful vision and, if possible, preventing metastases. Enucleation has largely been superseded by various forms of radiotherapy, phototherapy and local tumour resection, often administered in combination. Ocular outcomes are best with small tumours not extending close to the optic disc and/or fovea. Almost 50% of patients develop metastatic disease, which usually involves the liver, and is usually fatal within 1 year. Although UM metastases are less responsive than cutaneous melanoma to chemotherapy or immune checkpoint inhibitors, encouraging results have been reported with partial hepatectomy for solitary metastases, with percutaneous hepatic perfusion with melphalan or with tebentafusp. Better insight into tumour immunology and metabolism may lead to new treatments.

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.

Ruthenium brachytherapy for uveal melanoma - single institution experience

Purpose

The aim of this study was to report on results of uveal melanoma treatment with ruthenium-106 (¹⁰⁶Ru) brachytherapy with long-term follow-up, in terms of local tumor control, eye retention rate, radiation retinopathy, and patients’ survival.

Material and methods

Medical records of patients treated with ruthenium plaque due to uveal melanoma at the Department of Ophthalmology, Poznan University of Medical Sciences, Poland, between 1994 and 2014 were retrospectively reviewed.

Results

We identified 126 patients: 53 men, 73 women, mean age 60.04 years (range, 21-89). The largest basal diameter ranged from 4.04 mm to 18.9 mm (median, 10.67 mm), tumor height was 1.9 mm to 7.42 mm (median, 4.8 mm). Median scleral radiation dose was 570 Gy (range, 235-1,500 Gy), median apical dose 100 Gy (range, 60-129 Gy). Median follow-up was 66.5 months (range, 2-261 months). We noted a total of 19 (15%) recurrences. The actuarial rate of recurrence was 9.5% at 3 years, and 13.5% at 5 years postoperatively. Nine (7%) eye globes were lost, median time to enucleation was 5 years. The eye retention rate at 5 years was 92.7% and 81% at 10 years. Forty-three (34%) patients died before the end of the study, 24 (19%) of them due to metastatic disease. Metastatic death was related to: tumor size and TNM stage at presentation (p = 0.002 vs. p = 0.0006, respectively) but not to age, gender, and plaque dosimetry.

Conclusions

¹⁰⁶Ru brachytherapy is an effective, globe sparing treatment that provides good tumor control and a high rate of survival. However, some ocular complications tend to appear late post-treatment, and therefore long-term follow-up is advised.

Ruthenium-106 brachytherapy for iris and iridociliary melanomas

BACKGROUND AND PURPOSE

To evaluate ruthenium-106 (Ru106) brachytherapy as eye-conserving treatment of iris melanomas (IMs) and iridociliary melanomas (ICMs).

MATERIALS AND METHODS

Eighty-eight patients received Ru106 brachytherapy between 2006 and 2016. Primary outcome was local control, and secondary outcomes were metastasis, survival, eye preservation, complications and visual acuity (VA).

RESULTS

Overall median follow-up was 36 months. Of 88 patients, 58 (65.9%) had IM and 30 (34.1%) had ICM. ICM were on average larger and more advanced than IM. Local failure-free survival at 3years was 98.9% (SE 1.2%). Metastasis-free survival was 98.2% (SE 1.8%) at 3years; no deaths due to melanoma occurred during follow-up. Eye preservation rate was 97.7%. Treatment-related toxicities were mostly mild and observed in 80.7% of the patients. Common toxicities were worsening of pre-existing or new cataract (51.1%), dry eyes (29.5%) and glaucoma (20.5%). VA was not affected by Ru106 brachytherapy, with only 2.3% having VA <0.33 (low vision) at follow-up.

CONCLUSIONS

Ru106 for IM and ICM yielded excellent local control (98.9%) and eye preservation (97.7%). Toxicities were common, but mostly mild and transient. Moreover, Ru106 did not affect visual acuity.