Retinal tumours

Most tumours of the retina are extremely rare, the slightly more common ones (such as naevi) being benign. An overview of some of these tumours is provided here. They are all managed by ophthalmologists, usually in specialist or super-specialist centres (Liverpool, London and Sheffield), depending on the exact type of tumour.¹

There are also Retinoblastoma, Tumours of the Choroid and Choroidal Melanoma articles.

Retinal astrocytoma

A rare and benign tumour of the retina ± optic nerve head. Isolated tumours are not usually associated with systemic disease but multiple or bilateral tumours are seen in patients with tuberous sclerosis and less commonly with neurofibromatosis.

Symptoms and presentation

It is often asymptomatic but may present with leukocoria. Examination reveals a sessile yellow-white mass which can be mistaken for retinoblastoma. It may later become calcified. It may be associated with complications such as retinal detachment or glaucoma.

Treatment and management

They are benign and do not require treatment in themselves.² If acquired retinal astrocytoma can be diagnosed early then laser photocoagulation, cryotherapy, or radiotherapy could control the tumour and prevent any complications.

Retinal capillary haemangioma³

This is a rare, non-malignant but sight-threatening vascular hamartoma of the retinal or optic disc vasculature. It may be solitary or there can be multiple lesions. The former may occur in isolation (von Hippel disease) but about half of them occur in the context of systemic disease (von Hippel-Lindau (VHL) disease). All patients with multiple lesions have systemic disease. As there is an inherited component of VHL, if there is a single ocular lesion and a positive family history, the patient is deemed to have VHL. Various types of haemangiomas can occur:

• Capillary haemangioma (by far the most common presentation): small well-defined orange-red nodules with associated dilatation and tortuosity of overlying vessels.

• Exophytic haemangioma: sessile, ill-defined lesion associated with retinal oedema and haemorrhage ± retinal detachment.

• Optic nerve head haemangioma.

Symptoms and presentation

• Retinal capillary haemangiomas are most commonly detected in patients between the ages of 25 and 30 years.

• They may be asymptomatic and diagnosed on routine screening or may present with visual impairment (particularly in exophytic and optic nerve head haemangiomas).

Treatment and management

• Very small lesions may be managed conservatively but very closely monitored. Otherwise, treatment options include photocoagulation, cryotherapy or brachytherapy. Radiotherapy or surgical excision may also be considered.

• Treatment with anti-vascular endothelial growth factor is emerging as a promising option, although it is early days and there has yet to be more research into both safety and efficacy.

• Photodynamic therapy can be effective in reducing macular oedema associated with retinal capillary haemangiomas but this does not always correspond with an improvement in visual acuity, especially for juxta-papillary tumours.⁴

• Other treatment strategies include laser coagulation, radiation therapy, transpupillary thermotherapy and vitreoretinal surgery.

Juxta-papillary lesions behave differently from peripheral lesions. Some remain stable for years and treatment of these lesions should only be undertaken if vision is reduced or if there is lesion progression, as treatment usually leads to significant reduction in acuity due to adverse effects on the optic nerve and major retinal vessels.

Prognosis

• They show slow progression over time, but a small percentage may regress spontaneously.

• If they enlarge over time and are left untreated, the risk of exudation and subretinal fluid accumulation, cystoid macular oedema, and retinal detachment, increases. This can lead to progressive visual loss.

Retinal cavernous haemangioma

This is a rare, congenital, unilateral vascular hamartoma.⁵ In some patients, this is an autosomal dominant inherited condition which is associated with similar lesions of the skin and central nervous system (referred to as neuro-oculocutaneous phacomatosis or cavernoma multiplex).

Symptoms and presentation

• Most patients are asymptomatic. However, in patients with history of headaches, transient visual disturbance, or seizures, 80% had intracranial involvement.⁵

• Examination varies from small lesions that look a little like background diabetic retinopathy, to large vascular tortuosities which may show a fluid level within them, as the red cells sediment because of the sluggish flow of blood.

Treatment and management

This is usually managed conservatively although a large, non-resolving vitreous haemorrhage may require a vitrectomy (removal of the vitreous).

Prognosis

There is a variable outlook for patients with extensive lesions but most patients with localised pathology retain good vision.

Retinal racemose haemangioma

This is a rare, usually unilateral, congenital arteriovenous malformation resulting in a direct communication between arteries and veins without an intervening capillary bed.⁶ This results in dilated, tortuous fundal vessels.

Wyburn-Mason's syndrome refers to a subgroup of these patients who have a combination of retinal and intracranial arteriovenous malformations. In some instances, there are also lesions in the maxilla, mandible, orbit and facial skin.

Symptoms and presentation

it is usually a chance finding, although there may be visual impairment. High risk factors include older age, female gender, systemic hypertension and arteriosclerotic disease.

Treatment and management

No treatment is available for retinal lesions but intracranial ones may be managed with surgery, radiotherapy or embolisation.

Prognosis

• These vessels may occasionally result in haemorrhages if very large. Otherwise, there is neither deterioration nor improvement of vision.

• The development of extensive retinal ischaemia including macular ischaemia resulting in rubeosis (abnormal blood vessel growth on the iris and the structures in the front of the eye) has been reported.

• Wyburn-Mason's syndrome can be associated with irreversible neurological changes, stroke and death.

Retinal vascular proliferative tumour

This is a rare tumour involving the glial cells and the vessels and is characterised by single or multiple nodules on the retinal surface. It usually occurs in healthy patients and is often mistaken for other pathologies (eg, retinal angiomas or amelanotic choroidal melanomas).

However, in 25% of cases, it arises as a complication of other ocular disease such as retinitis pigmentosa, uveitis, retinal detachment, congenital toxoplasmosis, and Coats' disease.⁷

Symptoms and presentation

Most often, this presents in the fourth to sixth decade: there is blurring of vision ± floaters ± photopsia (flashing lights).

Treatment and management

Observation (small, uncomplicated peripheral lesions), cryotherapy, laser photocoagulation or brachytherapy. Occasionally, vitreoretinal surgery is required.

Prognosis

• This is varied between patients and may be non-progressing (or slowly progressing) in some patients and rapidly progressing in others. There is a guarded visual prognosis.

• There are a number of complications that can further limit the outlook: haemorrhage, exudation, macular oedema and retinal detachment.

Tumours of the retinal pigment epithelium

Congenital hypertrophy of the retinal pigment epithelium (CHRPE)

• CHRPE is a benign clinical entity characterised by round, flat, dark gray or dark brown plaques, which are primarily found in the retinal mid-periphery but may also occur in more anterior locations or in the posterior pole. Only 2% involve the macula.⁸

• It is is a clinical diagnosis. The lesion is usually asymptomatic and is found incidentally on routine ophthalmoscopic examination.

• CHRPE occurs in about 1% of the population. It is a proliferation of the retinal pigment epithelium associated with a hypertrophy of their melanin granules.

• It is said to be typical or atypical:
  

  • Typical CHRPE - these may be solitary or grouped lesions which show various pigmentation patterns. These need to be clinically distinguished from melanoma.

  • Atypical CHRPE - these multiple, haphazardly placed lesions show variability in size and degree of pigmentation. These are bilateral. They may be associated with familial bowel polyps.⁹

• Typical lesions are simply observed over time. Individuals with atypical lesions need a prompt investigation of their family history for bowel disease.

Retinal pigment epithelium adenoma¹⁰

This is an unusual and benign condition and presents as a black lesion. It is monitored and managed conservatively.

Retinal pigment epithelium adenocarcinoma¹⁰

This is an extremely rare condition which, up until now, has not been found to spread beyond the eye. It is more documented in females and tends to present as a prolonged inflammation of the eye. Atypical choroidal melanoma is the initial diagnosis in almost all cases. Treatment is with enucleation of the eye.

Combined hamartoma of the retinal pigment epithelium and retina

This is a rare, usually unilateral, malformation involving the retinal pigment epithelium, the retinal astrocytes and retinal vasculature. It is generally a sporadic condition that typically manifests in childhood with reduced visual acuity or strabismus.¹¹ Diagnosis later in life is far less common and bilateral cases are exceedingly rare.

Hamartoma of the retinal pigment epithelium

• Congenital simple hamartoma of retinal pigment epithelium (CSHRPE) is a rare, asymptomatic, and incidentally detected benign lesion.¹²

• It is an uncommon, well-circumscribed, jet-black lesion usually found at the macula.