Choroidal melanoma

Referral priority: Urgent

Urgently refer all patients with suspected choroidal melanoma to a hospital following local guidelines.

Written by
Marko Lukic
Edited by
Svein Tindlund and Jon Gjelle
Published
June 2023

Sections
01
Introduction

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02
Symptoms & Clinical features

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03
Diagnostic procedures

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04
Management and treatment

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05
References

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01

Introduction

Choroidal or uveal melanoma is the most common primary intraocular tumour and the second most common intraocular malignancy in adults.(1) Although rare (the age-adjusted incidence is 5.1. per million), choroidal melanoma is a severe eye condition, and missing diagnosis may lead to fatal outcomes.(2)

Established risk factors predispose the development of uveal melanoma, such as light iris colour, light skin colour, the tendency to freckle, Northern European ancestry, and positive family history of uveal melanoma.(3) Choroidal naevi, benign pigmented lesions in the eye, can be considered a risk factor for developing choroidal melanoma. However, it is important to note that the transformation rate of choroidal nevi into choroidal melanoma is relatively low, estimated to be between 1 in 5,000 and 1 in 8,845 cases. This means that out of a large number of individuals with choroidal naevi, only a tiny proportion will experience this transformation(4)

Nowadays, gene expression profiling provides a highly accurate molecular prognostication. Mutations in BAP1 are strongly associated with metastasis, whereas those in SF3B1 and EIF1AX are associated with a good prognosis.(5)

Uveal melanoma is classified based on its location. It may be posterior to the equator (85% of cases) or anterior to the equator of the eye (2-4% iris melanomas and 4-7% ciliary body melanomas).(6)

02

Symptoms & Clinical features

The symptoms in cases of choroidal melanoma are often absent, and they depend on lesion size and location. It has been proven that mortality rate and increased risk for metastases depend on the lesion’s size. Therefore, early recognition of choroidal melanoma is paramount when the lesion is small (≤3-mm thickness).7

The larger lesions and macula-involving ones are those which, in most cases, cause symptoms that include a decrease in vision, metamorphopsias, photopsia, and floaters. Rarely patients may experience red and painful eyes accompanied by increased intraocular pressure.

There are some typical signs which may raise suspicion about choroidal melanoma. These are:

  • A dome-shaped grey-brown choroidal lesion with irregular margins
  • Lesions that are more than 2 mm thick
  • Presence of subretinal fluid
  • Presence of orange pigment (lipofuscin)
  • Sentinel vessels (tortuous and dilated episcleral vessels overlying a melanoma)
  • Secondary glaucoma

Drusen and a halo of depigmentation around a pigmented choroidal lesion (naevus) are reassuring and most commonly present in choroidal nevi, not melanomas.

Image 1. The Optos colour fundus photography of an elevated choroidal lesion adjacent to the optic disc represents a choroidal melanoma.
Image 2. The real-colour fundus photography of an elevated choroidal lesion adjacent to the optic disc represents a choroidal melanoma.

How to recognise choroidal melanoma from choroidal nev

Shields and colleagues analysed 2,514 cases of choroidal nevi to determine predictive features of growth into melanoma. Using the data obtained in this study, they developed a mnemonic for these predictive features: “To Find Small Ocular Melanoma Using Helpful Hints Daily.”(8)

  • T: Thickness > 2 mm
  • F: Fluid (subretinal)
  • S: Symptoms (decreased vision, flashes, or floaters)
  • O: Orange pigment (presence of lipofuscin)
  • M: Margin within 3 mm of the optic disc (2 discs diameters from the optic disc)
  • UH: Ultrasonographic hollowness
  • H: Absence of surrounding halo. Nevi usually show a surrounding clear halo consisting of an atrophied retina.
  • D: Absence of drusen. Chronic changes known as drusen are typically observed in slow-growing lesions like choroidal nevi, not melanomas.
Image 3. The image represents a suspected choroidal naevus. - Please note that the nevus is elevated, indicating it is growing, and has drusen on its surface. The suspected presence of subretinal fluid.
Image 4. The OCT scan done over the nevus revealed the presence of subretinal fluid and drusen. There are no signs of lipofuscin or shaggy photoreceptors. According to the criteria, it meets only one risk factor. The lesion represents a nevus and requires monitoring.
Image 5. The image represents a real-colour fundus photo of a choroidal nevus. The nevus is located more than 2 DD from the optic disc margin, and it has the presence of drusen on its surface.

Choroidal melanocytic tumours with no risk factors have a 3% chance of growth at the five-year mark and most likely represent choroidal nevi. Tumours that show one risk factor have a 38% chance of growth, and those with two or more risk factors – growth is observed in over 50% of cases at the five-year mark.

03

Diagnostic procedures

Fundus photography is used to identify chorioretinal lesions and monitor them. Be aware that scanning laser ultra-widefield cameras represent pseudo-coloured photos, and the actual colour of the lesion on other machines or clinically on a slit lamp may look different.

Ultrasound and colour Doppler are important and, in most cases, primary diagnostic tools to diagnose choroidal melanoma. The most common representation of the tumour is a dome-shaped choroidal elevation. The other features that may be found are an acoustically hollow zone within the tumour, choroidal excavation, and subretinal fluid. The colour doppler confirms internal blood flow, which is not true – for nevi.

  Apical height  Largest basal diameter 
Small  1.0 – 2.5 mm  5.0 – 16.0 mm 
Medium  2.5 – 10 mm  less than 16 mm 
Large  more than 10 mm  more than 16 mm 


Table 1. The table displays the tumour size modified criteria as per COM study.

Spectral-domain OCT – is used to identify whether the pigmented lesion is elevated or flat and to reveal the presence of subretinal fluid, drusen, and lipofuscin.

Enhanced Depth Imaging Spectral-Domain OCT (EDI OCT) – this imaging modality evaluated deeper structures like choroids better than the standard OCT imaging. It may better visualise- shaggy photoreceptors, lipofuscin deposits, and thinning of choriocapillaris.(10)

Fundus autofluorescence – is used to identify lipofuscin. Lipofuscin is present in suspicious naevi and many melanomas. Lipofuscin fluorescence is brighter than drusen (drusen are typical in choroidal nevi).

04

Management and treatment

The management and type of treatment depend on the size, thickness, location, and activity of the tumour, the status of the opposite eye, and the patient’s age, general health, and psychological status. There are three primary goals in treating uveal melanoma: to preserve the valuable vision of the affected eye, to destroy the tumour, to prevent metastases/recurrence of the lesion.

The treatment of choroidal melanoma may involve using the following treatment options:(11-19)

  • Surgical (enucleation, orbital exenteration, local resection)
  • Radiotherapy (plaque brachytherapy, external beam radiotherapy)
  • Laser therapy (photocoagulation, transpupillary thermotherapy, photodynamic therapy)

The most common metastases are in the liver. Patients with extraocular metastases require a multidisciplinary approach, and the workup and management of those patients are beyond the scope of this article.

05

References

1 Singh AD, Turell ME, Topham AK. Uveal melanoma: trends in incidence, treatment, and survival. Ophthalmology. 2011 Sep 1;118(9):1881-5.

2 Virgili G, Gatta G, Ciccolallo L, Capocaccia R, Biggeri A, Crocetti E, Lutz JM, Paci E, EUROCARE Working Group. Incidence of uveal melanoma in Europe. Ophthalmology. 2007 Dec 1;114(12):2309-15.

3 Nayman T, Bostan C, Logan P, Burnier Jr MN. Uveal melanoma risk factors: a systematic review of meta-analyses. Current eye research. 2017 Aug 3;42(8):1085-93.

4 Singh AD, Kalyani P, Topham A. Estimating the risk of malignant transformation of a choroidal nevus. Ophthalmology. 2005 Oct 1;112(10):1784-9.

5 Field MG, Harbour JW. Recent developments in prognostic and predictive testing in uveal melanoma. Current opinion in ophthalmology. 2014 May;25(3):234.

6 Shields CL, Kaliki S, Furuta M, Mashayekhi A, Shields JA. Clinical spectrum and prognosis of uveal melanoma based on age at presentation in 8,033 cases. Retina. 2012 Jul 1;32(7):1363-72.

7 Shields CL, Furuta M, Thangappan A, Nagori S, Mashayekhi A, Lally DR, Kelly CC, Rudich DS, Nagori AV, Wakade OA, Mehta S. Metastasis of uveal melanoma millimeter-by-millimeter in 8033 consecutive eyes. Archives of Ophthalmology. 2009 Aug 1;127(8):989-98.

8 Shields CL, Furuta M, Berman EL, Zahler JD, Hoberman DM, Dinh DH, Mashayekhi A, Shields JA. Choroidal nevus transformation into melanoma: analysis of 2514 consecutive cases. Archives of Ophthalmology. 2009 Aug 1;127(8):981-7.

9 Pulido J. Combination of clinical factors predictive of growth of small choroidal melanocytic tumors. Evidence-Based Ophthalmology. 2000 Jul 1;1(4):222-3.

10 Shields CL, Kaliki S, Rojanaporn D, Ferenczy SR, Shields JA. Enhanced depth imaging optical coherence tomography of small choroidal melanoma: comparison with a choroidal nevus. Archives of Ophthalmology. 2012 Jul 1;130(7):850-6.

11 Shields CL, Shields JA. Recent developments in the management of choroidal melanoma. Current opinion in ophthalmology. 2004 Jun 1;15(3):244-51.

12 Robertson DM. Changing concepts in the management of choroidal melanoma. American Journal of Ophthalmology. 2003 Jul 1;136(1):161-70.

13 Shields CL, Shields JA, Gündüz K, Freire JE, Mercado G. Radiation therapy for uveal malignant melanoma. Ophthalmic Surgery, Lasers, and Imaging Retina. 1998 May 1;29(5):397-409.

14 Shields JA, Shields CL. Surgical approach to lamellar sclerouvectomy for posterior uveal melanomas: the 1986 Schoenberg lecture. Ophthalmic Surgery, Lasers, and Imaging Retina. 1988 Nov 1;19(11):774-80.

15 ZIMMERMAN LE, MC LEAN IW. An evaluation of enucleation in the management of uveal melanomas. International Ophthalmology Clinics. 1980 Jul 1;20(2):1-31.

16 Zimmerman LE, McLean IW, Foster WD. Does enucleation of the eye containing a malignant melanoma prevent or accelerate the dissemination of tumour cells? British Journal of Ophthalmology. 1978 Jun 1;62(6):420-5.

17 Manschot WA, van Peperzeel HA. Choroidal melanoma: enucleation or observation? A new approach. Archives of Ophthalmology. 1980 Jan 1;98(1):71-7.

18 Seigel D, Myers M, Ferris F, Steinhorn SC. Survival Rates After Enucleation of Eyes with Malignant Melanoma. Am J Ophthalmol 1979;87:761–765.

19 Shields JA, Shields CL, Donoso LA. Management of posterior uveal melanoma. Survey of ophthalmology. 1991 Dec 1;36(3):161-95.