Ocular Complications of Radiotherapy in Uveal Melanoma

Abstract

Uveal melanoma is the most common primary malignant intraocular tumor in adults. Radiation therapy has replaced enucleation and is now the preferred treatment in most cases. Nonetheless, around 70% of patients develop radiation-related complications, some of which are vision-threatening. The objective of this review is to present the most important complications associated with radiotherapy in the treatment of uveal melanoma and their pathogenesis, incidence, risk factors, and available preventive and therapeutic measures. The most common complications are cataracts, with a reported incidence ranging from 4% to 69%, and radiation retinopathy, reported in 5–68% of cases. Radiation-related complications are responsible for approximately half of secondary enucleations, the leading cause being neovascular glaucoma. A poor visual outcome is mainly associated with the presence of radiation retinopathy and radiation optic neuropathy. Therapeutic options are available for the majority of complications with the notable exception of optic neuropathy. However, many studies report a final visual acuity of less than 20/200 in more than 60% of treated eyes. Reducing complication rates can be achieved by lowering the dose of radiation, with the use of eccentric, customized plaques and careful planning of the irradiation delivery in order to protect structures vital to vision and by associating radiation therapy with other methods with the aim of reducing tumor volume.

New insights on clinical perspectives of FLASH radiotherapy: from low- to very high electron energy

“…Indeed, conservative treatment that is performed in approximately 70% of cases consists of RT that can be delivered in the presence of small-sized tumors by implantation of intraocular radioactive plaques (ruthenium or iodine) or in the presence of medium-sized tumors by external beam-accelerated protons ( 17 ). The key point in performing conservative treatment is represented by the preservation of the optic nerve, whose damage is related to the reduction or loss of vision ( 18 ). Thus, the spatial relationship between tumor and optic nerve is crucial and the choice of external beam protons therapy is based on the achievement of a very steep “fall-off” of RT dose outside the clinical target volume ( 19 ).…”

Seltene vaskuläre Erkrankungen der Netzhaut – Teil 1

“…Die Strahlenretinopathie ist eine Gefäßveränderung, die durch die Einwirkung von Protonen, β- oder γ-Strahlung auf die Gefäßwandarchitektur ausgelöst wird 24 , 25 . Strahlenretinopathien können nach perkutaner Radiatio mit Röntgenstrahlen, nach Brachytherapie mit 106 Ruthenium-Applikatoren bzw.…”

Deterioration of Visual Acuity after Brachytherapy and Proton Therapy of Uveal Melanoma, and Methods of Counteracting This Complication Based on Recent Publications

“…The increase in the popularity of brachytherapy was largely influenced by the publication of the results of the Collaborative Ocular Melanoma Study (COMS), which showed the lack of an advantage of enucleation over brachytherapy in terms of distant metastases and survival in the case of small- and medium-sized tumors [ 3 , 19 ]. In a COMS study, tumor size was defined as follows: small: 1.5–2.4 mm in height and 5–16 mm in diameter; medium: 2.5–10 mm in apical height and ≤16 mm in diameter; and large: >10 mm in apical height and >16 mm in diameter; these terms will be used to describe tumors of these dimensions in the remainder of this article, unless otherwise noted [ 3 , 11 ]. Brachytherapy has gradually become the most commonly used treatment for choroidal melanoma.…”

“…The main advantages of these methods include their minimal invasiveness, excellent local tumor control, relatively wide availability and low costs [ 20 , 25 , 26 , 28 , 29 ]. Some researchers have indicated their disadvantages in the form of lower precision and the associated higher number of post-radiation complications, mainly secondary glaucoma and enucleation compared with brachytherapy and proton therapy [ 11 , 20 , 30 ]. Other studies report no significant differences in the rate of complications between these therapies [ 18 ].…”

“…This is understandable, as the priority is to save the patient’s life. Nevertheless, the deterioration of eye function caused by radiation complications in the form of damage to structures such as the macula, optic disc and lens is a serious problem [ 9 , 11 ]. After brachytherapy, 49% of eyes experienced vision loss within three years and 68% within ten years.…”