Diffuse Iris Melanoma: Conservative Treatment with Proton Beam Therapy after Limbal Stem Cell Preservation or Enucleation?

PTCOG Ocular Statement: Expert Summary of Current Practices and Future Developments in Ocular Proton Therapy

Although rare cancers, ocular tumors are a threat to vision, quality of life, and potentially life expectancy of a patient. Ocular proton therapy (OPT) is a powerful tool for successfully treating this disease. The Particle Therapy Co-Operative Ocular Group) formulated an Evidence and Expert-Based Executive Summary of Current Practices and Future Developments in OPT: comparative dosimetric and clinical analysis with the different OPT systems is essential to set up planning guidelines, implement best practices, and establish benchmarks for eye preservation, vision, and quality of life measures. Contemporary prospective trials in select subsets of patients (eg, tumors near the optic disc and/or macula) may allow for dosimetric and clinical analysis between different radiation modalities and beamline systems to evaluate differences in radiation delivery and penumbra, and resultant tumor control, normal tissue complication rates, and overall clinical cost-effectiveness. To date, the combination of multimodal imaging (fundus photography, ultrasound, etc), ophthalmologist assessment, and clip surgery with radiation planning have been keys to successful treatment. Increased use of three-dimensional imaging (computed tomography/magnetic resonance imaging) is anticipated although its spatial resolution might be a limiting factor (eg, detection of flat diffuse tumor parts). Commercially produced ocular treatment-planning systems are under development and their future use is expected to expand across OPT centers. Future continuity of OPT will depend on the following: (1) maintaining and upgrading existing older dedicated low-energy facilities, (2) maintaining shared, degraded beamlines at large proton therapy centers, and (3) developing adapted gantry beams of sufficient quality to maintain the clinical benefits of sharp beam conformity. Option (1) potentially offers the sharpest beams, minimizing impact on healthy tissues, whereas (2) and (3) potentially offer the advantage of substantial long-term technical support and development as well as the introduction of new approaches. Significant patient throughputs and close cooperation between medical physics, ophthalmology, and radiation therapy, underpinned by mutual understanding, is crucial for a successful OPT service.

Ruthenium brachytherapy for iris melanoma

Purpose

The study aimed to review the long-term outcomes of ruthenium brachytherapy for iris and iridociliary melanoma.

Material And Methods

Medical records of patients who underwent ruthenium plaque treatment for iris and iridociliary melanoma at the Department of Ophthalmology, Poznań University of Medical Sciences, between 1999 and 2021 were retrospectively reviewed.

Results

We identified 24 patients, including 17 women and 7 men, with a median age of 61.5 years (range, 35-84 years). Median observation time before treatment was 3 months (range, 0-68 months). Nineteen (79%) patients received a treatment with 20 mm CCB plaque, 5 (21%) with 15 mm CCA plaque and 2 (8%) patients received total irradiation to the entire iridocorneal angle. Median follow-up was 67.5 months (range, 24-265 months). We noted one (4%) recurrence managed by irradiating the anterior segment. Twelve (50%) patients developed post-operative cataracts in a median time of 38 months following treatment, 5 (21%) required topical medications to control intraocular pressure, and one (4%) developed chronic macular edema (CME) that was managed with anti-VEGF therapy. Final visual acuity between 1.0 and 0.5 was observed for 16 (67%) patients, between 0.49-0.1 for 5 (21%) patients, and below 0.09 for 3 (12%) patients. Nine (37%) patients maintained final visual acuity stable; in 4 (17%) patients, it dropped more than 3 lines, and improved in 6 (25%) patients.

Conclusions

Ruthenium brachytherapy with standard applicators is an effective and safe way of treatment for iris and iridociliary melanoma. We observed no significant post-operative complications in a long-term observation.

Proton beam radiation for iris melanoma: case series and review of literature

Objective

Purpose of this study is to analyse the visual outcomes, the complication and eye retention rate as well as tumour control data of patients treated with proton beam radiation therapy (PBRT) for iris melanoma.

Methods

Retrospective case series and review based on patients’ records. All tumours were categorised according to the American Joint Committee of Cancer staging criteria for primary iris melanoma und underwent either sectorial or whole anterior segment PBRT.

Results

Thirteen cases were identified of which five received PBRT of the whole anterior segment and eight received sectorial PBRT. Local tumour control after a mean follow-up of 25 months was 92%. Complications after PBRT included cataract (46%), secondary glaucoma (31%), superficial keratitis (15%) and madarosis (8%). Complications were more common in patients necessitating irradiation of the entire anterior segment than in patients which received sectorial irradiation. Eye retention was achieved in all cases. No statistically significant difference in the mean best corrected visual acuity (BCVA) and intraocular pressure (IOP) was found before and after treatment. Comparison of mean BCVA and IOP between different treatment groups (complete anterior segment vs sectorial irradiation) at the last follow-up visit were also not significantly different. No patient developed metastatic disease during follow-up.

Conclusion

PBRT is a safe and vision preserving therapeutic modality for iris melanoma. Complete irradiation of the anterior segment is associated with higher complication rates.

Brachytherapy or enucleation in ring melanoma patients: which is better? Preliminary results of the authors' own experiences

Purpose

A retrospective evaluation of effectiveness of brachytherapy or enucleation in treatment of rare form of uveal melanoma: ring melanoma.

Material and methods

Analysis comprised 49 patients treated from 2000 to 2019 for ring melanoma involving ciliary body. In 15 patients, primary treatment consisted of brachytherapy (¹⁰⁶Ru or ¹²⁵I), whereas in 34 patients, eyeballs were enucleated. The evaluation concerned differences between analyzed groups relating to the clinical and histopathological features as well as overall survival, cancer-specific overall survival, and disease-free survival.

Results

No significant differences between the analyzed groups were found with regards to clinical and histopathological features, apart from intra-ocular pressure (increased in the enucleation group). Kaplan-Meier analysis did not reveal any significant differences between the group treated with enucleation and the group undergoing brachytherapy, both with regards to overall survival (p = 0.325) and cancer-specific overall survival (p = 0.477). A significant difference was observed in disease-free survival (p = 0.009), which was significantly shorter in the group undergoing brachytherapy. In the analysis of parameters of the applied brachytherapy, no significant differences between patients with and without local recurrence were found. Mean observation period was 350.8 weeks (range, 24-996 weeks, SD = 231.6). A local recurrence occurred in 11 (22.4%) patients, including 3 (6.1%) in enucleation and 8 (16.3%) after brachytherapy groups. Metastasis developed in 11 (22.4%) cases after a mean follow-up of 133 weeks (33.25 months), range 3-655 weeks.

Conclusions

Preliminary observations may suggest that brachytherapy in this rare form of uveal melanoma, such as ring melanoma involving the ciliary body, may be taken into consideration as a useful alternative to enucleation. However, the confirmation of such an approach requires a larger patients’ group to be gathered, and also a longer follow-up period. This is especially important in patients with a good baseline visual acuity in the affected eye, or when the neoplasm is present in the remaining eye with vision.

Uveal Melanoma - Standardised Procedure in Diagnosis, Therapy and Surveillance

BACKGROUND

Uveal melanoma is a rare intraocular tumour, for which there is currently no national evidence-based guideline in Germany. The aim of this project was to provide a common standard operating procedure (SOP) for the diagnosis, treatment and follow-up care of uveal melanoma, within the network of German leading oncology centres funded by German Cancer Aid. The SOP was created as part of a moderated consensus process.

RESULTS AND CONCLUSION

In a multistage process, a common SOP was developed for the diagnosis, therapy and follow-up of uveal melanoma, as based on current knowledge of the subject.

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.

Locally Invasive Diffuse Iris Ring Melanoma Presenting as Unilateral Severe Glaucoma: Case Report and Review of Molecular Genetics

We report the clinical history and histopathological findings in a case of diffuse iris ring melanoma (DIM) and review the most recent literature and modern molecular genetics of this entity. An 85-year-old Hispanic man presented with severe unilateral glaucoma, managed at an outside institution for 2 years prior to presentation. Diffuse pigmentation was noted in the angle, on the intraocular lens implant, and in the vitreous without clear demonstration of a mass on ultrasound biomicroscopy. Workup for metastatic cutaneous melanoma was negative. Histopathological examination of the enucleated eye revealed a mixed cell type iris ring melanoma with diffuse intraocular involvement. Gene expression profiling (GEP) revealed a class 2 molecular signature indicating a very high risk for metastases. Unilateral glaucoma presenting with marked pigmentation in the anterior chamber angle should be managed as melanoma until proven otherwise. Iris ring melanomas are known to have an aggressive clinical course, and recent molecular analyses indicate that they are likely primarily GEP class 2 with a very poor prognosis, similar to the majority of ciliary body melanomas.