Intraocular tumors

What you need to know about intraocular tumors

Anatomy

Anatomy

The eyeball is made up of three tissue layers that form its outer structure, and transparent substances that fill the inside.

The eye’s outer layers (the structure):

  • The corneo-scleral shell: the white outer layer (sclera), where the eye muscles attach. At the front, the sclera continues as the cornea, the transparent part that lets light into the eye.
  • The uvea: a vascular layer made up of:
    • The choroid, which nourishes the retina.
    • The ciliary body, which produces aqueous humor and controls focus by adjusting the lens.
    • The iris, the colored part of the eye, with a central opening called the pupil that regulates light entry.
  • The retina: the light-sensitive membrane lining the inside of the eye.


The inside of the eye (contents):

  • Aqueous humor: clear fluid in the front (anterior segment) of the eye.
  • The lens: the eye’s natural lens that enables focus and may develop cataracts over time.
  • The vitreous body: a transparent gel filling most of the back (posterior segment) of the eye.

Main intraocular tumors

The main intraocular cancers are either cancers of the retina, such as retinoblastoma in children, or cancers of the uvea, such as uveal melanoma, or metastases of cancers not originating in the eye. Some cancers, such as lymphoma, can involve either the uvea or the retina, depending on their nature.

Symptoms

The symptoms of ocular surface cancers are non-specific, meaning they can be found in other non-cancerous eye diseases. In most cases, these symptoms do not appear until the disease is in its late stages, and they are not always reason enough to seek medical advice.

Decreased vision

A decrease in visual acuity can occur when the tumor or its effects (such as retinal detachment or tumor invasion) affect the macula, the central area responsible for sharp vision.

Phosphenes

Sensation of seeing light, flashes, or patterns that aren’t caused by actual light entering the eye.

Floaters

Floaters, also known as myodesopsias, are small moving spots in the visual field caused by changes in the eye’s vitreous body.

Eye color modification

A white spot on the pupil (leukocoria) or dark pigmentation on the colored part of the eye (iris) or sclera (extra-scleral extension) may appear.

Management of intraocular tumors

The treatment of an intraocular tumor involves several procedures.

Surgery

Surgery for intraocular tumors may involve taking a biopsy from inside the eye, placing markers before proton therapy, or removing the eye in the most severe cases.

Radiotherapy

Intraocular tumors are often treated with radiotherapy, the main modality for the eye being proton therapy.