Gamma Knife radiosurgery for locally recurrent choroidal melanoma following plaque radiotherapy

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.

New Treatment Horizons in Uveal and Cutaneous Melanoma

Melanoma is a complex and heterogeneous malignant tumor with distinct genetic characteristics and therapeutic challenges in both cutaneous melanoma (CM) and uveal melanoma (UM). This review explores the underlying molecular features and genetic alterations in these melanoma subtypes, highlighting the importance of employing specific model systems tailored to their unique profiles for the development of targeted therapies. Over the past decade, significant progress has been made in unraveling the molecular and genetic characteristics of CM and UM, leading to notable advancements in treatment options. Genetic mutations in the mitogen-activated protein kinase (MAPK) pathway drive CM, while UM is characterized by mutations in genes like GNAQ, GNA11, BAP1, EIF1AX, and SF3B1. Chromosomal aberrations, including monosomy 3 in UM and monosomy 10 in CM, play significant roles in tumorigenesis. Immune cell infiltration differs between CM and UM, impacting prognosis. Therapeutic advancements targeting these genetic alterations, including oncolytic viruses and immunotherapies, have shown promise in preclinical and clinical studies. Oncolytic viruses selectively infect malignant cells, inducing oncolysis and activating antitumor immune responses. Talimogene laherparepvec (T-VEC) is an FDA-approved oncolytic virus for CM treatment, and other oncolytic viruses, such as coxsackieviruses and HF-10, are being investigated. Furthermore, combining oncolytic viruses with immunotherapies, such as CAR-T cell therapy, holds great potential. Understanding the intrinsic molecular features of melanoma and their role in shaping novel therapeutic approaches provides insights into targeted interventions and paves the way for more effective treatments for CM and UM.

Photon-based high-dose single-fraction radiosurgery, an effective treatment modality for recurrent uveal melanoma

Introduction

To evaluate and report the outcome of a patient with locally recurrent uveal melanoma (UM) previously treated with brachytherapy (BT), using a second personalized globe-sparing radiotherapy approach.

Material and methods

In June 2020, a 78-year-old man arrived at our institution with diplopia and suspected uveal melanoma. At the ophthalmological evaluation (B-scan and A-scan ultrasonography) a lesion in the right eye at 6-7 hours of about 5 mm thickness, with internal lacunar areas, approximately 7 mm away from the limbus, was observed. The patient underwent ruthenium plaque BT at a total dose of 110 Gy prescribed to the apex of the tumour. At the follow-up, the lesion was under control until September 2021, but it recurred with a satellite exudative detachment in the lower and temporal sectors 7-10 hours. At the B-scan the lesion had a maximum thickness of 4.6 mm. Subsequently, in a multidisciplinary discussion, one single fraction stereotactic radiosurgery was scheduled. The prescribed dose was 27 Gy in the de-novo lesion and 24 Gy in the previously irradiated site. Stereotactic radiosurgery was performed in October 2021.

Results

The time interval between the 2 treatments was 15 months. Twenty months after recurrence, local tumour control was observed, and no metastases were detected on follow-up examinations. No severe acute or late toxicity was observed due to the retreatment.

Conclusions

Photon stereotactic radiotherapy is a feasible, acceptably tolerated modality, and it represents an eye-preserving treatment also for patients with recurrent UM unfit for BT.

Radiation Retinopathy: Detection and Management Strategies

A gradual shift in trend from primary enucleation to globe salvaging radiation therapy for the management of ocular tumors has resulted in the rise of several post-treatment ocular complications including radiation retinopathy. Radiation retinopathy is a chronic, progressive, and occlusive vasculopathy that can manifest anytime between 1 month to 15 years after starting radiation therapy. The aim of treatment in most of these cases is to prevent further vision loss. Treatment options such as laser photocoagulation, anti-vascular endothelial growth factor and intraviral steroids have been described. However, despite several advances in diagnostic and therapeutic modalities, a significant proportion of eyes with radiation retinopathy eventually go blind. This review summarises some of the clinical features, investigative modalities, and recent therapeutic strategies used in the management of radiation retinopathy.

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.

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.

Radiation therapy for uveal melanoma: a review of treatment methods available in 2021

PURPOSE OF REVIEW

Radiation therapy has become the standard of care for the treatment of uveal melanoma. We intend to outline the current radiation therapy methods that are employed to treat uveal melanoma. We will outline their relative benefits over one another. We will also provide some background about radiation therapy in general to accustom the ophthalmologists likely reading this review.

RECENT FINDINGS

Four main options exist for radiation therapy of uveal melanoma. Because the eye is a small space, and because melanomas are relatively radioresistant, oncologists treating uveal melanoma must deliver highly focused doses in high amounts to a small space. Therapies incorporating external beams include proton beam therapy and stereotactic radiosurgery. Stereotactic radiosurgery comes in two forms, gamma knife therapy and cyberknife therapy. Radiation may also be placed directly on the eye surgically via plaque brachytherapy. All methods have been used effectively to treat uveal melanoma.

SUMMARY

Each particular radiotherapy technique employed to treat uveal melanoma has its own set of benefits and drawbacks. The ocular oncologist can choose amongst these therapies based upon his or her clinical judgment of the relative risks and benefits. Availability of the therapy and cost to the patient remain significant factors in the ocular oncologist's choice.

Ocular Complications After Radiation Therapy: An Observational Study

Aim of the Study

The study aims to quantify the incidence of ocular complications in patients irradiated on the head and neck area in our medical center, stratified by type of neoplasm and radiation dose received.

Materials and Methods

From an existing database of patients radio-treated in our center, we selected 25 patients irradiated in the 2011-2018 period. The patients had been treated for orbital lymphoma, nasopharyngeal carcinoma and cranial base meningioma. The selected patients received an ophthalmologic evaluation which included a complete ophthalmological and orthoptic assessment.

Results

Our results showed a significantly higher incidence of DES (dry eye syndrome) and corneal complications for eyes receiving a Dmax higher than 40 Gy, as well as for cataract incidence in eyes that had received a Dmax to the lens higher than 5 Gy. We found an overall thinning of the RNFL (retinal nerve fiber layer) in eyes that had received a Dmax higher than 50 Gy, as well as a greater MD (mean deviation) from normal visual field values.

Conclusion

In conclusion, we can say that the study confirms the presence of a correlation between the received radiation dose and the onset of eye complications, despite the small sample.

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.