Tumor-related Lipid Exudation and Associated Tumor-related Complications after Plaque Radiotherapy of Posterior Uveal Melanoma

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.

Ocular Complications of Radiotherapy in Uveal Melanoma

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.

Breakdown of the blood-eye barrier in choroidal melanoma after proton beam radiotherapy

PURPOSE

Irradiation of choroidal melanoma is a safe and globe preserving procedure. Chronic inflammatory processes and ischemia are the main reasons for secondary enucleation in the long run. The aim of this study was to determine whether intraocular inflammation and especially inflammatory response after proton beam therapy (PBT) is related to primary tumor characteristics such as height, tumor volume, and initial flare values.

METHODS

Twenty-six patients treated for uveal melanoma using PBT were included. All patients were examined for signs of inflammation using laser flare photometry (LFP). Each examination included assessment of the melanoma and fellow eye (which acted as the control) and imaging of the melanoma.

RESULTS

Significant differences of flare values between melanoma eyes and control group were found both at baseline (median 17.65 ph/ms (min 4, max 37.10), 7.45 ph/ms (min 0.80, max 16.40), respectively) and during follow-up (median 21.45 ph/ms (min 4.5, max 70.90); 6.05 ph/ms (min 2.40, max 16.40), respectively) (p < 0.001, Wilcoxon test). Flare values in melanoma eyes increased significantly after PBT (p = 0.005, Wilcoxon test) and after a follow-up of 94 days (median, 7-420 days). Flare values of the control group did not change (p = 0.946, Wilcoxon test). The increase of flare values correlated significantly with maximum tumor height and volume (Spearman-Rho 0.633, p = 0.001 and 0.519, p = 0.007, respectively).

CONCLUSION

LFP has proven to show significantly higher flare values in melanoma eyes as compared with the control group and provides data on the course of the inflammatory response after treatment. It may ease treatment planning both at baseline and during follow-up.

Anti-VEGF intravitreal bevacizumab for radiation-associated neovascular glaucoma

BACKGROUND AND OBJECTIVE

To report outcomes of intravitreal bevacizumab therapy in radiation-associated neovascular glaucoma (NVG).

PATIENTS AND METHODS

In this retrospective interventional case series, 12 eyes with NVG after radiation therapy for ocular malignancy were treated with periodic intravitreal injections of 1.25 mg bevacizumab. Outcome measures included changes in iris neovascularization, intraocular pressure (IOP), visual acuity, and pain.

RESULTS

One month after the first injection, iris neovascularization regressed in nine of 12 eyes (75%), and IOP decreased in eight of 12 eyes (67%) by a mean of 10.1 mm Hg. Patients were monitored for a mean of 26.5 months after their first injection. Six eyes subsequently underwent enucleation for pain control (four eyes; 66%), chronic uveitis (one eye; 17%), and tumor recurrence (one eye; 17%). All remaining patients experienced deterioration in visual acuity (range: 20/160 to no light perception), but pain control was good and IOP normalized in four patients.

CONCLUSION

Intravitreal bevacizumab therapy should be considered for patients with radiation-associated NVG who wish to avoid enucleation.

S100 expression by atypical megakaryocytes: a previously unreported potential pitfall in dermatopathology

Several types of large atypical epithelioid cells can mimic tumoral melanocytes and can therefore be a source of misdiagnosis of melanoma. Megakaryocytes are one of these types, and are not frequently mentioned in the literature. In the current report, we present the case of a 76-year-old man presenting with acute panmyelosis with myelofibrosis. The bone marrow biopsy contained atypical megakaryocytes that expressed S100 in the cytoplasm. We discuss how such aberrant expression could be a source of some diagnostic problems in dermatopathology, including cutaneous melanoma, metastasis of melanoma in bone marrow and metastasis of melanoma in sentinel lymph nodes.