2. • Choroidal melanomas are the most
common primary intraocular malignancies
in adults and accounts for 80% of all uveal
melanomas,but is still relatively
uncommon.
• Choroidal melanoma is a subtype of uveal
melanoma
3. Epidemiology
• Incidence of primary choroidal melanoma
is about 6 cases per 1 million population in
USA.
• Perhaps because of increased sunlight
exposure, there appears to be a higher
incidence of uveal melanoma in the
southern latitudes of the United States
• Other countries have almost same
incidence.
4. Etiology
• Risk factors are people with light-colored
iris, whites, median age-55 yrs.
• Sunlight exposure is a contributory factor.
• Predisposing diseases
1)family history of uveal melanoma
2) Iris or choroidal nevus
3)congenital ocular melanocytosis
4)dysplastic nevus syndrome(BAP1
mutation
5) Uveal melanocytoma
5. Pathophysiology
• Primary choroidal melanoma arises from
melanocytes within the choroid
• Three distinct cell types are recognized:
(1) spindle A cells
(2) spindle B cells
(3) Epithelioid cells
The last cell type usually has the most
aggressive behavior and carries a poorer
prognosis for the patient’s long-term
survival.
6. • Choroidal melanomas may be darkly
pigmented or amelanotic.
• They are typically dome-shaped.
• As they enlarge, they break through the
Bruch membrane and assumes a
mushroom configuration.
• Other shapes found are bilobular,
multilobular, and diffuse. The diffuse type
is characterized by lateral growth
throughout the choroid with minimal
elevation.
7. • Choroidal melanomas affect the retinal
pigment epithelium as they push against it
and deprive it of normal choroidal
circulation.
• Overlying retinal pigment epithelium
usually develops areas of atrophy, drusen,
and localized pigment epithelial
detachments.
• These changes can lead to choroidal
neovascularization over the tumor, with
consequent subretinal exudation,
hemorrhage, and fibrous plaque formation
8. • The tumor disrupts choroidal circulation
leading to ischemia that typically causes
degeneration of retinal photoreceptors and
other retinal neurons.
• The retina overlying the tumor can
separate into cystoid spaces (cystoid
macular edema).
• Exudation of fluid into the subretinal
space with consequent retinal detachment.
• Rarely, choroidal melanomas can impinge
into underlying posterior ciliary nerves,
causing severe ocular pain
9. • Tumor grows anteriorly, involving the
ciliary body, trabecular meshwork, and
lens, with consequent ocular hypotension
or hypertension, cataract, iris rubeosis,
vitreous hemorrhage or hyphema.
• Its metastatic potential depends on the
histopathologic aggressiveness of the
tumor cells.
• It can only spread hematogenously,
because there are no lymphatic vessels in
the eye. It most often metastasizes to the
liver, lung, bone, skin, and CNS.
10. • Less frequently, tumor can grow
transsclerally, through emissary channels,
and metastasize locally into the orbit or
rarely the conjunctiva.
• Choroidal melanoma almost never
extends through the optic nerve; when it
does, it is usually in juxtapapillary tumors
or in diffuse choroidal melanomas
11. Histologic Findings
• Histologic evaluation of the tumor after
enucleation can confirm the diagnosis and
determine the prognosis
12. Spindle A cells have elongated
nuclei and uncommonly have
mitotic figures
Spindle B cells have a prominent
nucleolus. They are found more
commonly and also have an elongated
profile but are slightly larger than
spindle A cells.
Epithelioid melanoma cells are
highly anaplastic, poorly cohesive,
polygonal and contain frequent
mitotic figures
13.
14. Adverse prognostic factors
1)Histological features include large
numbers of epithelioid cells, long and wide
nuclei, multiple nucleoli.
2)Chromosomal abnormalities: loss of
chromosome 3 and gains in chromosome
8, are associated with a poor prognosis.
Gains in the short arm of chromosome 6
carry a favourable prognosis.
15. 3)Size. Large tumors have a worse
prognosis than small tumors.
4)Extrascleral extension as tumor is more
likely to be advanced and aggressive.
5)Location. Anterior tumors involving ciliary
body have a worse prognosis.
6)Local tumor recurrence after
conservative treatment is associated with
poor survival. This is probably because the
recurrence is an indication that the original
tumor was relatively aggressive
16. Clinical Presentation
Patient history
• Choroidal melanomas remain asymptomatic for long time; they
may be found incidentally during ophthalmoscopy.
• SYMPTOMS:
• Blurred visual acuity
• Paracentral scotoma
• Painless and progressive visual field loss
• Floaters
• Severe ocular pain
• History of weight loss, marked fatigue, cough, or change in
bowel or bladder habits
17. • SIGNS:
• A solitary elevated subretinal grey-brown or
rarely amelanotic dome-shaped mass; diffuse
infiltration is uncommon
• About 60% are located within 3 mm of the optic
disc or fovea.
• Clumps of overlying orange pigment are
common due to lipofuscin.
• If the tumour breaks through the Bruch
membrane it acquires a ‘collar stud’ appearance.
• Associated haemorrhage and subretinal fluid
are common; the latter may become bullous and
mask the underlying lesion.
18.
19.
20. classification
Based on thickness and basal size.
The tumour is termed
-small (<10 mm diameter),
-medium (10-15 mm diameter,<10mm
height)
-large (>15 mm diameter, >10mm height)
21. Differential Diagnosis
Pigmented lesions:
• Choroidal nevus: Usually exhibits numerous surface drusen
without serous retinal detachment and little if any organge
pigments
• Melanocytoma:is deeply pigmented and usually located at the
optic disc.
• Congenital hypertrophy of the RPE: is flat, is often grey–black
and has a well-defined margin with lacunae.
• Haemorrhage in the subretinal or suprachoroidal space, for
example from choroidal neovascularization or retinal artery
macroaneurysm
• Metastatic cutaneous melanoma has a smooth surface, a light
brown colour, indistinct margins, extensive retinal detachment
and often a past history of malignancy
22. • Non-pigmented lesions
• Circumscribed choroidal haemangioma is typically
posterior, pink, dome-shaped and has a smooth
surface
• Metastasis is often associated with exudative
retinal detachment
• Solitary choroidal granuloma, e.g. sarcoidosis,
tuberculosis
• Posterior scleritis, which can present with a large
elevated lesion, but in contrast to melanoma pain is
a common feature.
23. • Large elevated choroidal neovascular
lesion, which can be eccentrically located,
usually in the temporal preequatorial region;
typically associated with exudate and fresh
haemorrhage, both of which rarely
accompany a melanoma.
• Prominent vortex vein ampulla is
characterized by a small, smooth, brown,
dome-shaped lesion, which disappears with
pressure on the eye.
24. Diagnosis and Investigations
• Clinical appearance
• FFA
• Ultrasound
• Radiography
• OCT
• Laboratory tests
• Invasive technique
• PET Scan
25. Fundus Fluorescein angiography
• FA is of limited diagnostic value because there is no
pathognomonic pattern.
• The most common findings are an intrinsic tumour
(‘dual’) circulation mottled fluorescence during the
arteriovenous phase and late diffuse leakage and
staining.
• the prominent vessels are seen within dome of the
tumour, thereby allowing both retinal and choroidal
vessels seen simultaneously(double circulation pattern)
• FA may, however, be useful in the differential diagnosis
of simulating lesions
26.
27. B-SCAN:
• B-scan is a routine test used in the evaluation of
any posterior segment mass.
• It is especially needed in patients with media
opacity.
• B-scan helps in
-establishing the diagnosis,
-to evaluate possible extraocular extension
-to estimate tumor size for periodic observation
-to plan therapeutic intervention.
28. Intraocular melanomas have several distinctive features on B scan:
• Low-to-medium reflectivity
• Excavation of underlying uveal tissue
• Shadowing of subjacent soft tissues
• An acoustic quiet zone at the base of the tumor called acoustic
hollowing
29. Radiography
Computed Tomography
• CT scan is more expensive and is not as
sensitive as ultrasonography.
• It is useful for visualizing extraocular
extension and may help differentiate
between choroidal or retinal detachment
and a solid tumor.
30. Magnetic Resonance Imaging
• MRI is more expensive and still remains less sensitive .
• Pigmented melanomas are seen as a high-density image.
• MRI also can be used to determine extrascleral extension and
distinguish surrounding fluid from the tumor.
31. OCT
• Measures dimensions and may
demonstrate associated subretinal fluid,
often before clinically apparent. Secondary
retinal changes are often evident overlying
the lesion.
32. Laboratory Studies
• Liver enzyme levels are indicated in any patient with uveal
melanoma, because the liver is the most common site of
choroidal melanoma metastasis.
• The most sensitive tests of hepatic function are serum levels of
the following:
-Alkaline phosphatase
-Aspartate and alanine aminotransferase
-Lactate dehydrogenase
-Gamma-glutamyl transferase
33. Invasive technique
• Fine-needle biopsy and incisional biopsy
are not usually required but may be helpful
in case where diagnosis is not established.
• Fine-needle biopsy is increasingly being
performed for prognostic purposes
• In opaque medias, ultrasound guided
approach is essential.
34. • It is done by 25 guage needle via
transvitreal or transcleral route.
• Risk of spread of cancerous cells in the
case of fine-needle biopsy is small
• Genetic analysis and karyotyping of biopsy
specimens have gained increasing
attention.
35. PET SCAN
• The comparative value of whole body
PET/CT imaging is not fully defined; it has
greater sensitivity for detecting metastatic
disease, particularly extrahepatic lesions,
but involves a substantial ionizing radiation
dose.
36. Treatment
The methods of patient management
depend on several factors:
-size, location, and extent of the tumor
-visual status of the affected eye and of the
fellow eye
-age and general health of the patient
-patient's wishes and fears
37. • Observation may be acceptable for posterior uveal
tumors where diagnosis is not well established.
• In particular, tumors of less than 2-2.5 mm in elevation
and 10 mm in diameter can be observed until growth is
documented.
• Photography and sequential ultrasonography for precise
measuring of the tumor’s dimensions are usually
necessary.
• Choice of treatment of choroidal melanoma remains
controversial in many respects.
• Although enucleation has been the treatment of choice
in the past, it appears that vision-sparing approaches
might offer similar degrees of ocular and metastatic
tumor control particularly because it is clear that in many
patients at the time of diagnosis, posterior uveal
melanomas already have spread through
micrometastasis.
38. Brachytherapy
• Brachytherapy (episcleral plaque radiotherapy)
is usually the treatment of first choice
• 1.Indications
-Tumours less than 20 mm in basal diameter
and upto 10 mm thick in which there is a
reasonable chance of salvaging vision.
39. 2)Technique
a.The tumour is localized by transillumination or
binocular indirect ophthalmoscopy.
b. A template consisting of a transparent plastic
dummy or metal ring with eyelets is sutured to the
sclera with a releasable bow
c.The sutures are loosened and used to secure the
radioactive plaque.
d. The plaque is removed once the appropriate
dose has been delivered, usually within 3–7 days.
40. 3)Tumour response is usually gradual
Tumour regression starts about 1–2 months after
treatment and continues for several years,
leaving a flat or dome-shaped pigmented scar.
4)Complications
Excessive irradiation causes cataract,
papillopathy and maculopathy. The irradiated
tumour can cause macular edema , retinal hard
exudates, serous retinal detachment, rubeosis
and neovascular glaucoma (‘toxic tumour
syndrome’).
5)Survival: similar to that following enucleation for
comparable tumors
41.
42. External beam radiotherapy
Irradiation with charged particles such as
protons achieves a high dose in the
tumour with a relatively small dose in the
superficial tissues.
Indications: tumours unsuitable for
brachytherapy either because of large size
or posterior location making positioning of
a plaque unreliable.
Survival results: similar to brachytherapy
or enucleation
43. Transpupillary thermotherapy
• Transpupillary thermotherapy uses an infrared
laser beam to induce tumour cell death by
hyperthermia but not coagulation. It is useful
adjunct to radiotherapy.
Indications :
1)Small choroidal melanoma when radiotherapy
is inappropriate because of poor general health
or reduced life expectancy.
2)After radiotherapy, as a treatment for
exudation threatening vision.
44. Enucleation
Indications:
-large tumour size,
-optic disc invasion,
-extensive involvement of the ciliary body or angle,
-irreversible loss of useful vision and
-poor motivation to keep the eye.
-It is essential to perform ophthalmoscopy after draping the
patient to ensure that the correct eye is treated.
-Manipulation of the eye should be kept to a minimum.
-Orbital recurrence is rare if there is no extraocular tumour
spread or if any such extension is completely excised.
45. Other procedures:
Pars plana vitrectomy endoresection
endoresection for posterior choroidal melanomas
Block excision
It is reserved for small tumors covering less than one third of
the globe’s circumference.
Trans-scleral choroidectomy
Indicated for tumours too thick for radiotherapy but
usually less than 16 mm in diameter.
46. • Systemic chemotherapy and
immunotherapy
- No distinct role where there is no
evidence of metastatic spread
47. Further outpatient care
• Irrespective of the treatment modality chosen, patients with
choroidal melanomas need to be observed carefully for many
years.
• This is particularly true for small tumors, when the diagnosis is
not established clearly.
• Close observation and measurement of the dimensions of the
tumors is critical.
• Repeat examinations usually are performed about every 3
months initially, and if no changes are seen, follow-up care is
performed every 6 months. If growth of the lesion is detected,
consider further treatment.
• The goal of successful treatment is not necessarily reduction in
size but long-term arrest of the tumor’s growth.
• The possibility of intraocular or extraocular tumor recurrence
should be kept in mind.
• Early detection of distant metastases may affect management
and survival.
