Choroidal Melanoma Simulating Adenoma of the Retinal Pigment Epithelium Arising at the Site of Congenital Hypertrophy of the Retinal Pigment Epithelium

Subretinal Exudation: The First Presentation of Untreated Choroidal Melanomas

Introduction

This case series aims to present the unusual clinical manifestation of subretinal exudation in patients diagnosed with untreated choroidal melanoma. A total of 886 patients were diagnosed and treated for primary choroidal melanoma between November 2017 and June 2023 at St. Paul's Eye Unit, Royal Liverpool University Hospital, UK. The fundus photographs were screened for lipid exudates by two independent clinical experts. The patients' demographics, clinical manifestations, and imaging features were analysed, whereas the location of exudation was documented with fundus photographs and optical coherence tomography (OCT). The histopathological and genetic results were also analysed in cases with tumour biopsy available.

Case Presentations

Eight cases with subretinal exudates were identified (n = 8/886, 0.90%). No gender predilection was noticed (male/female 1:1), whereas the mean age was 51 years (range 39-79). Four patients were asymptomatic at presentation, 2 patients reported reduced visual acuity, and 2 patients presented with photopsia. OCT scans revealed the presence of subretinal fluid and subretinal exudates, while the ultrasound showed medium or low internal reflectivity in 7 out of 8 cases. The biopsy analysis was available in 4 cases, all showing low-risk spindle cell choroidal melanoma with disomy 3.

Conclusion

Lipid exudates are an atypical fundoscopic finding in patients with untreated choroidal melanoma. The subretinal location could differentiate them from other retinal vascular conditions and facilitate early diagnosis and intervention. Interestingly, all cases tested cytogenetically were of low metastatic risk; these exudates may, therefore, be a positive clinical prognostic sign.

Retinal Pigment Epithelial Adenoma: Initial Treatment Outcomes following Episcleral Brachytherapy

Introduction

We aim to explore the safety and efficacy of episcleral brachytherapy as a primary management option for eyes with retinal pigment epithelial (RPE) adenoma.

Methods

Retrospective chart review of the demographic, clinical, ancillary, and postoperative outcome data of patients with RPE adenoma in 2 tertiary referral centers. Tumor regression, final visual acuity, and complications were assessed.

Results

Five patients (3 females and 2 males) were included. Four of the 5 eyes had peripheral and mid-peripheral lesions, while one tumor was juxtapapillary. Three eyes were treated with ruthenium-106 (100 Gray), and 2 received iodine-125 episcleral plaques (85 Gray). All eyes showed clinical and imaging-based evidence of regression. Four eyes had stable or improved visual acuity, while 1 eye exhibited one line loss of visual acuity due to radiation retinopathy. Local recurrence was not observed in any eye over a median follow-up of 24 (range 6-112) months.

Conclusions

Episcleral brachytherapy is an effective management option for select cases of RPE adenoma that is capable of achieving tumor regression while maintaining favorable visual acuity. The initial safety profile of brachytherapy is good without significant vision-compromising complications.

Diagnostic methods and therapeutic options of uveal melanoma with emphasis on MR imaging-Part I: MR imaging with pathologic correlation and technical considerations

Uveal melanoma is a malignant neoplasm that derives from pigmented melanocytes of the uvea and involves, in order of decreasing prevalence, the choroid, ciliary body and iris. Its prognosis is related to histopathologic and genetic features, tumor size and location, extraocular extension. The diagnosis is fundamentally based on clinical evaluation (ophthalmoscopy, biomicroscopy) and ultrasonography. MRI is useful in case of untransparent lens or subretinal effusion. Moreover, MRI has a significant role to confirm the diagnosis, in the evaluation of the local extent of the disease with implications for treatment planning, and in the follow-up after radiotherapy treatment. Uveal melanoma can show different morphologic features (lentiform, dome or mushroom shape) and often determines retinal detachment. MR appearance of uveal melanoma mainly depends on the melanin content. Uveal melanoma typically displays high signal intensity on T1-weighted images and low signal intensity on T2-weighted images. Nevertheless, imaging appearance may be variable based on the degree of pigmentation and the presence of areas of necrosis or cavitation. Differential diagnosis includes other uveal lesions. The radiologists and in particular MRI play a significant role in the clinical management of uveal melanoma. 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 first section we summarize the MR anatomy of the eye and describe ophthalmological and radiological imaging techniques to diagnose uveal melanomas, with emphasis on the role of MR imaging. Additionally, we review MR imaging appearance of uveal melanomas.

A pilot trial of intravital microscopy in the study of the tumor vasculature of patients with peritoneal carcinomatosis

Aberrancies in the tumor microvasculature limit the systemic delivery of anticancer agents, which impedes tumor response. Using human intravital microscopy (HIVM), we hypothesized that HIVM would be feasible in patients with peritoneal carcinomatosis (PC). During cytoreductive surgery with hyperthermic intraperitoneal chemotherapy for PC, HIVM was performed in both tumor and non-tumor areas. The primary outcome was HIVM feasibility to measure vessel characteristics. We secondarily evaluated associations between HIVM vessel characteristics and oncologic outcomes (RECIST response to neoadjuvant therapy and disease-specific survival). Thirty patients with PC were enrolled. Nineteen patients (63.3%) received neoadjuvant therapy. HIVM was feasible in all patients. Compared to non-tumor (control) areas, PC areas had a lower density of functional vessels, higher proportion of non-functional vessels, smaller lumenal diameters, and lower blood flow velocity. Qualitative differences in these vessel characteristics were observed among patients who had partial response, stable disease, or progressive disease after receiving neoadjuvant therapy. However, no statistically significant relationships were found between HIVM vessel characteristics and oncologic outcomes. These novel findings comprise the first-in-human, real-time evidence of the microscopic differences between normal and tumor-associated vessels and form the basis for our larger, ongoing clinical trial appropriately powered to determine the clinical utility of HIVM (NCT03823144).

Retinal Pigment Epithelium Adenoma and Adenocarcinoma: A Review

Adenoma and adenocarcinoma of the retinal pigment epithelium (RPE) are rare intraocular tumours that are often misdiagnosed as posterior uveal melanoma or other simulating lesions. It is important to be able to differentiate these tumours from melanoma for 3 reasons. First, an inability to rule out melanoma often tilts the management towards enucleation. Second, management options like radiotherapy and local resection which work well for melanoma may not be easily applied to these tumours. Third, and most importantly, patients with melanoma need a lifetime follow-up to rule out metastases (metastatic dormancy) whereas RPE tumours hardly metastasize. An abruptly elevated, often deeply pigmented tumour, with a prominent retinal feeding artery and a draining vein causing exudation, should raise a suspicion of RPE tumours. RPE tumours have a remarkable local invasive potential but a low metastatic potential. Most RPE tumours require treatment due to local complications. Small, asymptomatic tumours can be generally observed. Enucleation is still the gold standard of treatment, although local resection has been reported in selected cases with good results. Here, we provide a comprehensive review of the demographic, clinical, and imaging features of true acquired neoplasms of the RPE, namely adenoma and adenocarcinoma, the ways to differentiate them from melanoma, their clinical course and prognosis, and Options for their management.

Adenoma and Adenocarcinoma of the Retinal Pigment Epithelium: A Review of 51 Consecutive Patients

PURPOSE

To describe the clinical and imaging characteristics, pathologic features, and management options of retinal pigment epithelium (RPE) adenoma/adenocarcinoma.

DESIGN

Retrospective case series.

PARTICIPANTS

Fifty-one patients with RPE adenoma/adenocarcinoma.

METHODS

Treatment options for the patients included observation, partial lamellar sclerouvectomy (PLSU), enucleation, and others.

MAIN OUTCOME MEASURES

Factors related to visual acuity (VA) outcomes (>2 Snellen lines loss, poor final VA [≤20/200], good final vision [≥20/40]), tumor growth, and need for enucleation.

RESULTS

The mean patient age at diagnosis was 51 years, and the majority of patients were white (40/51, 78%) and female (34/51, 67%). Primary management included observation (29/51, 57%), PLSU (9/51, 18%), enucleation (4/51, 8%), or others (9/51, 18%). Outcomes revealed decreased VA (10/32, 31%), poor final VA (17/32, 53%), good final VA (11/32, 34%), tumor growth (12/25, 48%), and need for enucleation (7/51, 14%). By multivariable analysis, features predictive of decreased VA included increasing baseline tumor thickness (P = 0.01) and presence of vitreous hemorrhage (P = 0.05). Factors predictive of poor final VA included presence of exudative retinal detachment (P = 0.004), baseline VA 20/50 to 20/150 (P = 0.008), and baseline VA ≤20/200 (P = 0.01). Absence of feeding and/or draining vessel was predictive of good VA (P = 0.004). Tumor growth was associated with multiple treatments (P = 0.02). Increased tumor thickness (P = 0.03) and presence of exudative retinal detachment (P = 0.01) were predictive of enucleation.

CONCLUSION

RPE adenoma/adenocarcinoma can simulate choroidal melanoma. Greater tumor thickness, vitreous hemorrhage, exudative retinal detachment, and poor baseline VA predict worse visual outcome and greater risk for enucleation.