Factors associated with elevated intraocular pressure in eyes with iris melanoma

Links between melanoma germline risk loci, driver genes and comorbidities: insight from a tissue-specific multi-omic analysis

Genome-wide association studies (GWAS) have associated 76 loci with the risk of developing melanoma. However, understanding the molecular basis of such associations has remained a challenge because most of these loci are in non-coding regions of the genome. Here, we integrated data on epigenomic markers, three-dimensional (3D) genome organization, and expression quantitative trait loci (eQTL) from melanoma-relevant tissues and cell types to gain novel insights into the mechanisms underlying melanoma risk. This integrative approach revealed a total of 151 target genes, both near and far away from the risk loci in linear sequence, with known and novel roles in the etiology of melanoma. Using protein-protein interaction networks, we identified proteins that interact-directly or indirectly-with the products of the target genes. The interacting proteins were enriched for known melanoma driver genes. Further integration of these target genes into tissue-specific gene regulatory networks revealed patterns of gene regulation that connect melanoma to its comorbidities. Our study provides novel insights into the biological implications of genetic variants associated with melanoma risk.

Iris melanoma: Review of clinical features, risks, management, and outcomes

Primary uveal melanoma is rare and affects approximately 8,000 persons per year worldwide. This malignancy can involve the iris, ciliary body, and choroid. Of these three structures, the iris is the least commonly affected site, representing only 4% of all uveal melanomas. Iris melanoma can arise from iris melanocytic nevus, iris melanocytosis, or de novo. In a longitudinal study of 1,611 patients with iris nevus, transformation into melanoma, using Kaplan-Meier estimates, was found in 2.6% by five years and in 4.1% by 10 years. The factors that predicted growth of iris melanocytic nevus into melanoma are denoted by a letter (ABCDEF) guide: A for age ≤40 years old at presentation (hazard ratio [HR] = 3, P = .01), B for blood (hyphema) (HR = 9, P < .0004), C for clock hour of tumor inferiorly (tumor location) (HR = 9, P = .03), D for diffuse flat tumor configuration (HR = 14, P = .02), E for ectropion uveae (HR = 4, P = .002), and F for feathery ill-defined margins (HR = 3, P = .02). At diagnosis, iris melanoma has a mean cross-sectional diameter of 5.5 mm and thickness of 2.1 mm, often with tumor seeding (28%) and secondary glaucoma (35%). We provide a comprehensive review of iris nevus and melanoma to explore relevant demographic and clinical data, risk factors for tumor growth, management, and prognosis, with the hope that clinicians will be more comfortable in understanding this rare malignant condition.

Effectiveness of treatment for iris melanoma: surgical versus radiotherapeutic approaches

OBJECTIVE

To evaluate the effectiveness of preventing metastasis for each major treatment modality for iris melanoma.

DESIGN

Retrospective case series.

PARTICIPANTS

Three hundred consecutive eyes with iris melanoma at a single tertiary referral centre for ocular oncology.

METHODS

Retrospective analysis of eyes with iris melanoma, both with (n = 69 eyes) and without (n = 231 eyes) ciliary body extension, was undertaken for metastasis-free survival at 5, 10, and 20 years based on type of treatment, including globe-sparing surgical resection (n = 169 eyes), plaque radiotherapy (n = 74 eyes), or enucleation (n = 57 eyes).

RESULTS

For the total population, 5-, 10-, and 20-year metastasis-free survival rates were 95%, 93%, and 87%, respectively, and there was no difference in metastatic rates for tumours with versus without ciliary body extension (p = 0.95). Noninferiority was demonstrated for surgical resection and plaque radiotherapy, with metastasis-free survival rates of 98%, 97%, and 94% for surgical resection and 94%, 94%, and 89% for plaque radiotherapy (p = 0.002). The rates for globe salvage were 94%, 92%, and 90% for surgical resection and 94%, 86%, and 86% for plaque radiotherapy (p = 0.003). However, metastasis-free survival was worse in patients who underwent enucleation (86%, 67%, and NA; p < 0.001).

CONCLUSIONS

Metastasis-free survival and globe salvage following plaque radiotherapy and surgical resection are not inferior to either, but eyes undergoing enucleation demonstrated a lower metastasis-free survival, likely because enucleation is performed for larger, more extensive melanomas, often with secondary glaucoma. In this analysis, iris melanoma with ciliary body involvement did not increase the risk of metastasis.

Glaucoma and Systemic Disease

Glaucoma is the leading cause of irreversible blindness in the world. Due to its potential to cause permanent vision loss, it is important to understand how systemic conditions and their respective treatments can be associated with or increase the risk for developing glaucoma. In this review, we examined the literature for up-to-date discussions and provided commentary on glaucoma, its pathophysiology, and associated risk factors. We discuss systemic diseases and the impact, risk, and mechanism for developing glaucoma, including pharmacologically induced glaucoma; inflammatory and auto-immune conditions; infectious, dermatologic, cardiovascular, pulmonary, renal, urologic, neurologic, psychiatric and systemic malignancies: intraocular tumors; as well as pediatric, and genetic conditions. The goal of our discussion of systemic conditions including their commonality, mechanisms, treatments, and associations with developing glaucoma is to emphasize the importance of ocular examinations and follow-up with the multidisciplinary teams involved in the care of each patient to prevent unnecessary vision-loss.

Iris melanoma: factors predictive of post-management secondary glaucoma in 271 cases at a Single Ocular Oncology Centre

BACKGROUND/AIMS

To identify factors predictive of post-management secondary glaucoma in eyes with iris melanoma.

METHODS

Patients with iris melanoma who were conservatively managed on the Ocular Oncology Service, Wills Eye Hospital from 1970 to 2016 were included. Charts were retrospectively reviewed, and binary logistic regression analysis was performed. Main outcome measures were factors predictive of post-management glaucoma, defined as intraocular pressure (IOP) > 22 mmHg following melanoma treatment.

RESULTS

Of 271 patients with iris melanoma, melanoma-related glaucoma was identified in 40 (15%) at presentation and post-management glaucoma developed in 75 (28%) at a mean of 103.7 months (range:1.0-120.0). Comparison (post-management glaucoma vs. no glaucoma) revealed patients with post-management glaucoma presented with worse visual acuity (20/50-20/150) (17% vs. 5%, p = 0.001), increased mean tumour basal diameter (5.1 mm vs. 4.3 mm, p = 0.004), greater melanoma-related increased IOP on presentation (24.1 mmHg vs. 16.2 mmHg, p < 0.001), diffuse tumour shape (9% vs. 4%, p = 0.01), American Joint Committee on Cancer (AJCC) T4 category (7% vs. 2%, p = 0.03), and extraocular tumour extension (7% vs. 2%, p = 0.03). Risk factors for post-management glaucoma identified by multivariate analysis included melanoma-related increased IOP at presentation (OR:1.1, [1.08-1.22] per 1-mmHg increase, p < 0.001), increased mean tumour basal diameter (OR:1.17, [1.02-1.33] per 1-millimetre increments, p = 0.03), advanced AJCC clinical T subcategory (OR:1.23, [1.04-1.46] per 1-subcategory increments, p = 0.02) and plaque radiotherapy treatment (OR:2.32, [1.13-4.75], p = 0.02).

CONCLUSION

Features of iris melanoma that predicted post-management glaucoma included melanoma-related increased IOP on presentation, advanced AJCC clinical T subcategory, increased mean tumour basal diameter, and plaque radiotherapy treatment.

Proton Therapy for 166 Patients with Iris Melanoma: Side Effects and Oncologic Outcomes

OBJECTIVE

To investigate the oncologic and functional outcomes of a large cohort of patients with a favorable stage of circumscribed and diffuse iris melanoma who underwent primary proton treatment and the risk factors related to initial tumor characteristics and the treatment field architecture.

DESIGN

Retrospective, single-center, case study.

PARTICIPANTS

We reviewed 225 patients with iris melanoma who were consecutively treated with proton beam therapy at our institution between 1998 and 2020.

METHODS

We performed Kaplan-Meier time-to-event analyses and multivariate Cox proportional hazard analyses to identify the impacts of tumor characteristics and target volumes on oncologic and functional outcomes.

MAIN OUTCOME MEASURES

We measured local tumor control, eye preservation rates, metastasis-free survival, cataract and glaucoma-directed surgery, intraocular pressure, and changes in visual acuity.

RESULTS

Of the 192 patients with tumors confined to the iris (T1a-c) who underwent proton therapy as primary treatment, a total of 166 patients (mean age, 58.4 years; 88 women) with a minimum follow-up of 6 months were included. Multifocal or diffuse tumor spread was present in 77 (46.4%) patients. The median follow-up time was 54.0 (interquartile range, 27.4-91.8 months) months. Local recurrence occurred in 2 patients (1.2%) with circumscribed iris melanoma. Enucleation was a rare event (n = 5, 3%) and no patient developed metastatic disease. A large-treatment field (full aperture, involving > 10 clock hours) was identified as a risk factor for the development of secondary glaucoma (hazard ratio [HR], 6.3; P < 0.001) and subsequent surgical interventions (HR, 10.85; P < 0.001). The large-treatment field group showed a significant decline in visual acuity (logarithm of the minimum angle of resolution > 0.3; log-rank P < 0.0001), which was associated with secondary glaucoma (HR, 3.40; P = 0.002).

CONCLUSIONS

Proton therapy provides an effective, noninvasive treatment option for patients with a favorable stage of iris melanoma. Irradiation of the anterior segment for up to 10 clock hours is associated with a low risk of the development of secondary glaucoma and vision loss.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Molecular characteristics of uveal melanoma and intraocular tumors

Malignant melanomas within the eye present different types of metabolic and metastatic behavior. Uveal melanoma (UM) affects a quarter of a million individuals in the USA; however, the molecular pathogenesis is not well understood. Although UV radiation is a risk factor in cutaneous melanomas, it is not crucial for UM progression. Apart from chromosomal abnormalities, numerous major tumorigenic signaling pathways, including the PI3K/Akt, MAPK/ERK, Ras-association domain family 1 isoform A and Yes-associated protein/transcriptional co-activator with PDZ-binding motif signaling pathways, are associated with intraocular tumors. The present review describes the current insights regarding these signaling pathways that regulate the cell cycle and apoptosis, and could be used as potential targets for the treatment of UMs.

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

Objectives

Iris melanomas represent 2-3% of uveal melanomas; the diffuse variant accounts for approximately 10% of all iris melanomas. Different treatment modalities for diffuse iris melanomas (DIM) have been proposed depending on the local status as well as the age and general condition of the patient.

Methods

This study is a single-centre retrospective case series describing the diagnosis, treatments and outcomes of DIM. Treatment consisted of enucleation or proton beam therapy (PT) of the whole anterior segment. Patients who were treated with PT benefitted from limbal stem cell preservation before irradiation.

Results

Between 1996 and 2016, a total of 14 patients with DIM presented to our institution and were included in the database. The global survival was 86%. The median follow-up was 4.6 years (range 4 months to 15 years). Only 1 patient (7%) developed metastatic disease of the DIM (gastric location). No patient developed liver metastasis. Seven patients were treated by enucleation and 7 by PT after limbal stem cell preservation. After a conservative attempt, local tumour recurrence occurred in 2 patients at 2 years, requiring enucleation. The cornea was clear after irradiation in all patients. Cataract (n = 6) and glaucoma (n = 4) were the main complications after irradiation.

Conclusions

DIM is a very rare tumour. The global survival is excellent. Conservative treatment with PT is an efficient alternative to enucleation and allows good local tumour control. Cataract and glaucoma are the main radiation-related complications, but the corneal status was excellent due to the stem cell harvest prior to radiotherapy.

Outcomes of Glaucoma Drainage Device Surgery in Eyes with Treated Uveal Melanoma

Aim

We report patient safety and intraocular pressure (IOP) control after placement of a glaucoma drainage device (GDD) in eyes with a history of treated malignant uveal melanoma.

Methods

A retrospective review of the records of patients with uveal melanoma was performed. Outcomes were local tumor recurrence, rate of metastases, and to-nometric success, based on survival curves, defined as IOP < 21 mm Hg.

Results

Eleven eyes with choroidal melanoma, 4 with iris melanoma, and 1 with ciliary body melanoma were followed for a median (interquartile range) of 2.1 (1.1-3.2) years. Two subjects developed liver metastases; one had monosomy 3 and tumor gene expression profile class 2. The other case with ciliary body melanoma was negative for monosomy 3. There were no cases of local treatment failure. Mean preoperative IOP decreased from 30.5 ± 7.7 to 15.9 ± 8.1 mm Hg at 1 year after surgery (1-year success rate 80%).

Conclusions

Our case series with a median follow-up of 2 years shows that placing a GDD in patients with treated uveal melanoma does not expose patients to greater risk of local or extraocular recurrence. A larger series and longer follow-up time are required to fully evaluate the safety of GDDs in this clinical scenario.

Advanced choroidal melanoma with a desirable aesthetic outcome after enucleation: A case report

Choroidal melanoma is a rare ocular tumor. The present study reports the case of a 66-year-old male who presented with chronic headache and progressive visual loss. Physical eye examination and combined A- and B-mode ultrasonography detected choroidal melanoma. Due to tumor characteristics the eye was enucleated restoring the orbital volume with a 22 mm intraorbital bioceramic sphere implant. The eye was subjected to histopathological examination that confirmed the choroidal melanoma, 2 cm in diameter and 0.8 cm in elevation, occupying almost half of the globe. Microscopically, the neoplasm comprises mostly of epithelioid cells and fewer Type B spindle cells, with intense pigmentation. AJCC staging for the melanoma was T4b. The patient was fitted with an artificial eye after enucleation. Thirteen months after initial diagnosis, liver metastases were confirmed during his scheduled follow-up.

Proton Beam Therapy for Iris Melanomas in 107 Patients

PURPOSE

To report on the clinical characteristics and outcomes for patients with iris melanoma using proton therapy.

DESIGN

Retrospective study.

PARTICIPANTS

One hundred seven patients with iris melanoma from 3 regional ophthalmologic centers.

METHODS

A retrospective study was conducted for iris melanoma patients from 3 regional ophthalmologic centers referred to and treated at a single proton therapy facility between 1996 and 2015.

MAIN OUTCOME MEASURES

At each follow-up visit, examinations included measurement of best-corrected VA, slit-lamp, examination, indirect ophthalmoscopy, and ultrasound biomicroscopy.

RESULTS

With a median follow-up of 49.5 months, 5 of 107 patients experienced a local relapse within a median of 36.3 months. The cumulative incidence of relapse was 7.5% at 5 years. All 5 patients showed involvement of the iridocorneal angle (P = 0.056). Diffuse iris melanoma showed a higher risk of relapse (P = 0.044). Four patients showed out-of-field relapse and 1 showed angular relapse. Three patients were retreated with proton therapy, whereas 2 other patients, one with T1b disease and another with diffuse T3 disease, underwent secondary enucleation. None of the patients experienced metastases nor died of iris melanoma. Vision improved in 59.4% of patients (n = 60/101). However, cataracts occurred in 57.4% of the 54 patients (n = 31) without cataract or implant at diagnosis. Secondary glaucoma was reported in 7.6% of the patients (n = 8), uveitis in 4.7% (n = 5), and hyphema in 3.7% (n = 4). All but 5 cases of complications were mild, transient, and not sight limiting after treatment. Five cases of glaucoma, including 1 with uveitis, were severe and associated with visual deterioration.

CONCLUSIONS

Proton therapy showed efficacy and limited morbidity in iris melanomas.

A review on ocular findings in mouse lemurs: potential links to age and genetic background

Mouse lemurs, the world's smallest primates, inhabit forests in Madagascar. They are nocturnal, arboreal and dependent on vision for their everyday lives. In the last decades, the grey mouse lemur became increasingly important for biomedical research, in particular aging research. Experiments which require the combination of visual fitness and old age consequently depend on a solid knowledge of ocular pathologies. Although ocular diseases in mouse lemurs have been described as being common, they have not received much attention so far. Yet it is important to know when and why ocular diseases in captive mouse lemurs may occur. This review aims to provide a comprehensive overview of known ocular findings in mouse lemurs. It summarizes the frequency of ocular findings in captive mouse lemur colonies and points to their likely causes and treatment options based on the evidence available from other animals and humans. In addition, it shall be discussed whether age or genetic background may affect their development. This review may be used as a reference for future studies which require an assessment of visual performance in mouse lemurs and help to evaluate observed clinical signs and ocular diseases. Furthermore, the high incidence of specific diseases may provide new perspectives and set the groundwork for a new animal model for ocular research.

Proton beam therapy for presumed and confirmed iris melanomas: a review of 36 cases

BACKGROUND

To report the clinical features and outcomes of iris melanomas treated by proton beam therapy.

MATERIALS AND METHODS

A retrospective study was conducted at the Croix-Rousse University Hospital of Lyon, Department of Ophthalmology, in 36 patients treated by proton beam therapy for presumed (n = 29) and confirmed (n = 7) iris melanomas between July 1997 and October 2010. Ciliary body melanomas with iris involvement were excluded. The patients' mean age was 54.4 years (range, 22-82 years). The average tumor diameter was 3.8 mm (range, 2.5-8.0). The iridocorneal angle was invaded by the tumor in 47% of cases (n = 17), the ciliary body in 17% of cases (n = 6), and the sclera in 3% (n = 1). Raised intraocular pressure was present before treatment in 11.1 % of cases (n = 4). Tumor biopsy was performed in 19% of cases (n = 7). Four patients had undergone an initial incomplete surgical excision of tumor before radiotherapy. Surgical preparation of the eye with tantalum ring positioning had been performed in all cases 3-4 weeks before irradiation. The prescribed dose was 60 Cobalt Gray Equivalent (CGE) of proton beam radiotherapy delivered in four fractions on four consecutive days.

RESULTS

The median follow-up was 50 months (mean 60.5, range 15-136). One patient (2.7%) was lost to follow-up. None of the patients showed tumor progression, local recurrence, or metastasis. None of the patients required secondary enucleation. Cataract was developed in 62% of patients, glaucoma in two cases (6%) after irradiation, and hyphema with the aggravation of pre-existing glaucoma in one patient. No patients developed neovascular glaucoma.

CONCLUSIONS

Proton beam therapy appears to be the treatment of choice for the conservative treatment of iris melanomas with excellent tumor control and an acceptable rate of complications. Longer follow-up studies on a larger series is necessary to consolidate these results.

Secondary glaucoma as initial manifestation of uveal melanoma

PURPOSE

Secondary glaucoma can be induced by a variety of local ocular problems. Intraocular tumors may initially present as secondary glaucoma.

METHODS

8 consecutive patients with secondary glaucoma were found to have uveal melanoma. Thorough examination included detailed history, fundus examination with scleral depression, B scan ultrasonography, and CT/MRI scanning techniques.

RESULTS

A single case presented with spontaneous hyphema, two patients presented with secondary glaucoma, extraocular melanoma and metastases, a single case was found to have angle block by an iridociliary ring melanoma and 4 cases presented with neovascular glaucoma. Enucleation was necessary in all 8 cases.

CONCLUSIONS

General ophthalmologists should be aware of these rare initial manifestations of intraocular tumors as secondary glaucoma. Enucleation would be recommended in most cases of intraocular malignancy manifesting as secondary glaucoma. One should be extremely cautious in doing a penetrating surgery in such cases.

Iris melanoma management with iodine-125 plaque radiotherapy in 144 patients: impact of melanoma-related glaucoma on outcomes

PURPOSE

To evaluate the outcomes of iris melanoma managed with plaque radiotherapy on the basis of the initial presence or absence of glaucoma.

DESIGN

Retrospective, comparative case series.

PARTICIPANTS

A total of 144 patients.

INTERVENTION

Custom-designed iodine-125 plaque radiotherapy delivering planned 8000 cGy to melanoma apex using transcorneal application.

MAIN OUTCOME MEASURES

Tumor control and treatment-related complications.

RESULTS

Of 144 patients with iris melanoma, glaucoma was present at the initial visit in 58 (40%). Causes of elevated intraocular pressure included angle infiltration by melanoma in 50 patients (86%), angle neovascularization in 4 patients (7%), and hyphema in 4 patients (7%). At presentation, the eyes displaying iris melanoma with glaucoma (vs. without glaucoma) were statistically more likely to display angle tumor (66% vs. 43%), with minimal thickness (1.9 vs. 2.9 mm), and melanoma seeding in iris stroma (7 vs. 3 clock hours) and angle (5 vs. 2 clock hours). Plaque radiotherapy was performed in all cases. Kaplan-Meier estimates at 7 years post-treatment revealed no statistical differences in outcomes of local recurrence (14% vs. 15%), enucleation (14% vs. 11%), or metastasis (2% vs. 0%) comparing eyes with and without glaucoma. Of the entire group, multivariate analysis for factors predictive of recurrence included partial (vs. complete) anterior segment irradiation and postradiotherapy glaucoma. Factors related to enucleation included diabetes mellitus, poor initial visual acuity, higher radiation dose to tumor apex, and tumor recurrence. There were no factors predictive of metastasis.

CONCLUSIONS

Iodine-125 plaque radiotherapy provides adequate tumor control for iris melanoma with a low metastatic potential of 1% at 7 years. Iris melanoma with secondary glaucoma showed a statistically significant greater likelihood of flat tumor with iris and angle seeding and no difference in outcomes compared with eyes without glaucoma.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Baerveldt implant for secondary glaucoma due to iris melanoma

BACKGROUND

Proton beam therapy (PBT) is effective in the treatment of iris melanoma. Reported complications after PBT are radiation-induced cataract and raised intraocular pressure (IOP). Filtering glaucoma surgery has generally been avoided because of fears of seeding.

CASE REPORT

A 37-year-old man presented with a self-discovered, pigmented lesion on his right iris. Four years later, the pigmented lesion was diagnosed as an iris melanoma, because of documented growth. The patient was treated with PBT but developed secondary glaucoma one month later. The IOP could not be controlled despite maximal medical therapy and selective laser trabeculoplasty (SLT). Finally, Baerveldt implant surgery was performed, resulting in an IOP lowering to 10 mmHg and stabilization of the glaucomatous visual field loss.

CONCLUSION

Our case demonstrates that Baerveldt implant surgery is a reasonable therapy for glaucoma following successful radiotherapy of iris melanoma.

Glaucomas Secondary to Intraocular Melanomas

Intraocular melanomas are not common entities but often lead to secondary glaucoma. Intraocular melanomas should be considered in the differential diagnosis of patients with unilateral glaucoma. Occasionally, the workup of unilateral glaucoma leads to a diagnosis of an intraocular melanoma. Intraocular melanomas represent the majority of intraocular tumors. The prevalence of intraocular melanomas as well as associated secondary glaucomas will be reviewed. The workup needed for unilateral glaucoma will be covered in detail. Treatment options for secondary glaucomas include topical and oral medications as well as argon laser trabeculoplasty and transscleral cyclophotocoagulation.

Diffuse iris melanoma: Report of a case with review of the literature

Diffuse iris melanoma is an uncommon variant of anterior uveal melanoma. It is characterized by heterochromia and unilateral glaucoma secondary to angle invasion, and can be difficult to diagnose. We present a patient who had been managed for left-sided raised intraocular pressure with latanoprost eye drops for 12-months and pigmentary changes were subsequently noted. On referral to the Ocular Oncology Unit, Sydney, iris melanoma was suspected and confirmed on iridectomy, and the eye was eventually enucleated.

Proton beam therapy for iris melanoma: a review of 15 cases

AIM

To report results of proton beam therapy for iris melanoma.

METHODS

A retrospective case series of 15 patients with nonresectable iris melanomas treated with proton beam therapy between August 1998 and August 2004. The main outcome measures were (1) local tumour control, (2) complications, and (3) eye retention.

RESULTS

Of the 15 cases, 11 patients showed documented growth (including two cases of local recurrence following iridocyclectomy) while a further three cases were biopsy-proven melanoma. One patient presented with a newly acquired vascular nodule of the iris associated with angle seeding and glaucoma. Tumour control at mean follow-up of 34 months was 93% (14 of 15 eyes). Common complications included glaucoma in 53% (five patients had glaucoma prior to irradiation), dry eye (27%) and cataract in three patients (20%). Eye retention was possible in 80% (12 cases).

CONCLUSION

Proton beam therapy is an effective treatment for cases of nonresectable iris melanoma. The major complications are cataract and glaucoma.

Iris melanoma: pathology, prognosis and surgical intervention

A case of an iris melanoma in a 58-year-old woman is described. The clinical and pathological findings are discussed, highlighting the correlations between histopathology and prognosis for iris melanoma, which differ markedly from choroidal melanoma. The mixed cellular pathology of this iris melanoma (containing both spindle B cells and epithelioid cells) carries a higher metastatic rate than tumours composed exclusively of either. This contrasts with choroidal melanoma, where the presence of epithelioid cells is the strongest pathological marker for a poor prognosis. The ocular outcome that can be achieved with local surgical excision of a well-delineated iris melanoma that does not involve the angle is discussed.

Anterior segment tumors: current concepts and innovations

The most common anterior segment tumors are primary neuroepithelial cysts, uveal melanomas, metastatic tumors, and benign tumors. In the majority of cases, the diagnosis can be made utilizing a careful clinical history and ocular examination. Ultrasound examination (low and high frequency) has become an indispensable tool used to determine tumor extension and involvement of the surrounding structures. In particular, high-frequency ultrasound has been used to uncover iris pigment epithelial cysts, to allow for the diagnosis of small ciliary body melanomas, and to measure tumors for plaque radiation planning. Whereas fluorescein angiography and computerized tomography have come to play a limited role, fine-needle aspiration biopsy has been found to be quite helpful in selected cases. Once the diagnosis is established, treatment decisions depend on the tumors' location, size, local extension, patterns of growth, and secondary complications. Most anterior segment tumors can be observed for growth prior to treatment. Other options include local resection (iridectomy, lamellar sclerouvectomy, or eye-wall resection) and radiation (ophthalmic plaque or external beam). Enucleation is typically employed if these eye- and vision-sparing treatments are not possible and for uncontrollable secondary glaucoma. This review examines the unique role of high-frequency ultrasonography for the diagnosis and treatment of anterior segment tumors as well as an overview of clinical practice.

[Relative contraindication of latanoprost in iris tumors with secondary glaucoma]

INTRODUCTION

Melanocytic iris tumors are often benign and merely require regular follow-up. Evident growth, increasing pigmentation and secondary glaucoma, however, are possible signs of a malignant transformation.

PATIENT

We present a 34-year-old male patient showing a localized, mildly prominent hyperpigmentation of the right iris expanding over 2 h. The lesion had been known since childhood and increasing intraocular pressure (IOP) was treated with timolole, dipivefrin and finally with latanoprost.

PROGRESSION

The patient was seen for the first time at our hospital 4 years previously, presenting an IOP of 28-30 mmHg of the right eye. The tumor had developed marked heterochromia and a nodular prominent surface, the chamber angle was partly closed and completely hyperpigmented. The ciliary body was not affected by the tumor and standard ultrasound revealed a maximum thickness of 1.2 mm. Over the last 4 years, IOP and heterochromia had increased but without growth of the tumor. An excisional biopsy of the prominent portion was refused by the patient.

DISCUSSION

The melanocytic iris tumor described shows malignant characteristics such as progressive heterochromia and secondary glaucoma. However, increasing iris pigmentation can also be caused by topical application of latanoprost. With the evidence of absent tumor growth, there is no reason to suggest malignant degeneration. Generally, in iris naevi or tumors requiring regular follow-up, application of latanoprost should be avoided in order not to conceal the alteration of pigmentation as possible malignant conversion.

Custom-designed plaque radiotherapy for nonresectable iris melanoma in 38 patients: tumor control and ocular complications

PURPOSE

To evaluate plaque radiotherapy for iris melanoma.

DESIGN

Prospective noncomparative interventional case series.

METHODS

For 38 patients, custom-designed plaque radiotherapy using iodine 125 isotope was applied overlying the cornea with a tumor apex dose of 80 Gy. The main outcome measures were tumor control and ocular complications using Kaplan-Meier estimates and Cox proportional hazards regression analysis.

RESULTS

In all cases, the melanoma was nonresectable owing to large or discohesive tumor. The tumor configuration was nodular in 24 cases (63%) and flat (diffuse) in 14 (37%). The mean tumor basal diameter was 9 mm (range 4 to 13 mm). Solid tumor extended into the anterior chamber angle in 36 eyes (95%). Tumor seeds were noted on the iris stroma for a mean of 7 clock hours and in the anterior chamber angle for a mean of 4 clock hours. Five-year follow up revealed tumor metastasis in 0% and tumor recurrence in 8% of patients. Visual acuity of 20/200 or worse was found in 16% at 5 years. Radiation-related complications at 5 years included corneal epitheliopathy (9%), cataract (70%), and neovascular glaucoma (8%). No patients developed corneal necrosis, scleral necrosis, retinopathy, or papillopathy. After treatment, the combined incidence of tumor-related and radiation-related elevated intraocular pressure at 5 years was 33%. Enucleation was necessary in 13% at 5 years, for tumor recurrence (n = 3) and patient preference (n = 1).

CONCLUSIONS

Plaque radiotherapy is a useful alternative to enucleation for eyes with nonresectable iris melanoma. Tumor control is 92% at 5 years, but related complications, especially cataract and elevated intraocular pressure, should be anticipated.

Diffuse iris melanoma: a report of 25 cases

BACKGROUND

Diffuse iris melanoma is a rare variant of iris melanoma that has a flat growth pattern and often presents as unilateral hyperchromic heterochromia and glaucoma. There have been no large clinical reports of diffuse iris melanoma.

DESIGN

Single-center retrospective case series.

PARTICIPANTS

Twenty-five consecutive patients with diffuse iris melanoma.

METHODS

A review of the clinical features, management, histopathologic analysis, and prognosis was performed.

MAIN OUTCOME MEASURES

Clinical features, histopathologic features, management, and prognosis.

RESULTS

At the time of diagnosis, the mean patient age was 49 years. The initial complaint was unilateral darker eye color in 13 cases (52%) and blurred vision in 6 (24%). Six patients (24%) were symptom free. On presentation elsewhere, the initial diagnosis was iris melanoma or nevus in 11 cases (44%) and glaucoma in 14 (56%), 8 (32%) of whom had prior laser or surgical treatment for glaucoma. The 25 patients were observed for a mean of 30 months before the diagnosis of melanoma was suspected and referral to our center for evaluation. The mean intraocular pressure at referral was 36 mmHg, and the mean number of clock hours involved by tumor was 11. Heterochromia iridis was present in all 25 cases (100%), corectopia in 23 (92%), and ectropion iridis in 21 (84%). Associated findings included unilateral cataract in 8 (32%), a prominent episcleral (sentinel) vessel in 7 (28%), and anterior chamber inflammation in 5 (20%), and synechiae (anterior or posterior) in none. The tumor was managed by enucleation in 22 cases (88%) and by plaque brachytherapy in 3 (12%). Five cases (20%) were classified as spindle melanoma, 17 (68%) as mixed cell type, and 3 (12%) as epithelioid cell type. Therefore, histopathologic examination showed that 80% of cases contained epithelioid cells. All 22 enucleated cases were found to have tumor invasion in the trabecular meshwork. Tumor invasion of Schlemm's canal was found in 18 (82%), minor pars plicata in 12 (55%), and episclera in 7 cases (28%). Of seven cases with episcleral invasion, four underwent surgical treatment for glaucoma. Excluding one recent case, the patients were observed for a mean of 78 months. Liver metastasis developed in 3 cases (13%).

CONCLUSIONS

Diffuse iris melanoma is a serious ocular condition that causes unilateral hyperchromic heterochromia and secondary glaucoma, often leading to a delay in diagnosis. Local invasion of adjacent ocular structures is common, and distant metastasis occurs in 13% of cases at mean follow-up of 78 months.