Treatment of Ocular Tumours

This section gives a brief overview of the various methods available for treating ocular tumours benign and malignant. More detailed information will be given to you once the most appropriate form of treatment for your particular tumour has been selected.

Plaque radiotherapy

This treatment is indicated for selected choroidal melanomas, conjunctival melanomas, choroidal haemangiomas and some tumours travelling to the eye from elsewhere. It enables a high dose of radiation to be focused onto a small area and has the advantage of being completed in a few days.

: Ruthenium plaque sutured to the eye wall directly over the tumour

: Good result after plaque radiotherapy, with black area of dead tumour (i.e. 'pile of soot') surrounded by white area.

The radiotherapy is administered by means of a saucer-shaped plaque, which has an inner, concave radioactive surface and an outer, convex protective shield.

The treatment involves:

A 45 minute operation under general anaesthesia, during which the plaque is placed against the wall of the eye directly over the tumour and held in place with sutures.
A second 25 minute operation under general or local anaeasthesia. The plaque is removed between one and seven days later, once the appropriate dose of radiation has been delivered.

We can select between ruthenium plaques, which are suitable for tumours up to approximately 5 mm thick, and iodine plaques, which can treat tumours up to 9 mm thick (albeit giving a higher dose of radiation to normal ocular structures). Ruthenium plaques are available within a day, whereas iodine plaques need to be constructed for each patient and this takes up to six weeks.

This radiation does not travel beyond the eye so there is no risk of hair loss or other general problems.There is no radiation once the plaques is removed.

Proton beam radiotherapy

: Plan for proton beam radiotherapy

This treatment is selected when the tumour is not suitable for the more convenient plaque radiotherapy, that is, small intraocular melanomas near the optic nerve, some choroidal haemangiomas, iris melanomas, and some large intraocular melanomas.

The treatment involves:

A 45 minute operation under general anaesthesia, to suture four tiny tantalum markers to the wall of the eye, at known locations in relation to the tumour margins;
Treatment planning for half a day at Clatterbridge Centre for Oncology (CCO); and
A five day course of radiotherapy at CCO, with each session taking about one hour.
An examination at your local eye hospital about eight weeks after the radiotherapy.

The radiotherapy at CCO is completely painless.

Stereotactic radiotherapy

This treatment involves directing radiation at the tumour from several directions so as to maximize the dose of radiation within the tumour while minimizing the radiation delivered to surrounding healthy tissues. This treatment is still experimental and not performed at our hospital.

Trans-scleral local resection

Trans-scleral local resection involves the removal of the tumour through a large trapdoor in the wall of the eye. To prevent bleeding, the intraocular pressure is lowered, using hypotensive anaesthesia, monitoring the brain and heart using special equipment. A radioactive plaque is usually placed over the treated area to reduce the chances of tumour recurrence, and this is done either at the end of the operation or a month later. Each trapdoor operation takes about three to four hours. This is difficult surgery and therefore performed only when an intraocular melanoma is too large for radiotherapy.

: Right eye showing choroidal melanoma before local resection (a)

: Post-operative view showing (a) inner surface of white sclera, (b) retinal vein, and (c) small residual haemorrhage.

Trans-retinal endoresection

: Endoresection involves (a) tumour removal, (b) temporarily filling the eye with air, (c) laser treatment, and (d) filling the eye with silicone

The tumour is sucked up a fine, metal tube, which is passed through a hole in the retina. Laser treatment is given to prevent tumour recurrence. The eye is filled with silicone oil for about twelve weeks to hold the retina in place until scarring has firmly welded the retina in position. Plaque radiotherapy may be administered as an additional measure to prevent tumour recurrence.

The treatment involves:

a two-hour operation under general anaesthesia, and
after approximately 12 weeks, a 30- minute operation under local anaesthesia to remove the silicone oil.

This operation is 'semi-experimental' and controversial. It is therefore used only as a last resort when a tumour is located next to the optic nerve and when it is important to conserve vision.

Conjunctival excision

Discrete tumour nodules on the surface of the eyeball can be removed surgically, if not too extensive. This operation is usually performed under general anaesthesia.

Transpupillary thermotherapy

Laser treatment involves heating the tumour for about one minute, using an infrared laser beam. The treatment lasts about half an hour and is delivered under local anaesthesia on an outpatient basis.

This treatment is suitable for small tumours, when there is uncertainty as to whether the lesion is a benign mole or a malignant melanoma. It is also useful for melanomas that are leaking excessive amounts of fluid and fat after previous radiotherapy.

Cryotherapy

Very thin tumours on the surface of the eyeball can be given 'freezing treatment', using either a spray of liquid nitrogen or a special pencil-like device. This treatment can be administered under local or general anaesthesia.

External beam radiotherapy

External beam radiotherapy is indicated for some choroidal haemangiomas and some tumours travelling to the eye from another part of the body. These tumours respond to doses of radiation that are usually low enough to be well tolerated by the whole eye. The equipment required for this treatment is available at most hospitals. To reduce complications, the treatment is given in small doses over days or weeks.

Photodynamic therapy

With this treatment, a dye called Verteporfin is injected into a vein in the arm, so that it circulates around the body and through the tumour. After a few minutes, an infra-red laser is directed at the tumour for about 83 seconds and this activates the dye so that it kills the tumour. This treatment is painless. It is necessary to keep out of bright sunlight for about two days afterwards.

Photodynamic therapy is very effective for circumscribed choroidal haemangiomas and has almost completely superseded radiotherapy. There is evidence that this treatment may also be useful for some other tumours.

Topical chemotherapy

If too extensive for surgical removal, very thin tumours on the surface of the eye can be treated with special drops ('weedkiller'), consisting of Mitomycin C or 5-FU. These drops are administered on an outpatient basis, with each course lasting between four and seven days. It is usually necessary to repeat the course of treatment every two or four weeks, about three or four times.

Intraocular injections

Intraocular injections, which are quite painless, are given under local anaesthesic. These include steroids for inflammation, chemotherapeutic agents such as methotrexate for lymphoma, and anti-angiogenic factors, which shrink blood vessels.

Enucleation

Removal of the eye is indicated when the chances of conserving a useful eye are low and when the risk of complications is high.

The operation is performed under general anaesthesia. A long-acting anaesthetic injection is given to minimize pain during the initial post-operative period. The enucleated eye is replaced by a ball implant. The eye muscles are sutured to this implant so that the artificial eye will move with the fellow eye. At the end of the operation a transparent 'conformer', similar to a rigid contact lens, is placed in the socket. About ten weeks after surgery, this is replaced by a 'tailor-made' permanent artificial eye, at the patient's referring hospital. The artificial eye is like a coloured contact lens, painted to match the fellow eye. This usually gives a good cosmetic result.

To avoid any risk of Creuzfeld Jacob Disease (CJD) the operation is performed with disposable instruments and tissue transplants are not used.

A district nurse will visit you daily to help you with the conformer. If any problems arise, you can phone the Specialist Ocular Oncology Nurse (i.e. Key Worker) at any time (0151 706 3976).

Exenteration

In very rare instances it is necessary to remove not only the eye but also the surrounding tissues and the eyelids. A special cosmetic prosthesis is made after the operation.

Multidisciplinary Meetings

Meetings with staff from different disciplines (e.g. ophthalmologists, nurses, pathologists, radiotherapists, oncologists, etc) are held:

at the end of each new patient clinic, to discuss diagnosis and treatment plans;
before proton beam radiotherapy to agree therapeutic strategy;
after biopsy, local resection or enucleation, to discuss findings of microscopic tissue examination;
after any adverse radiotherapy events, to determine whether complications might be avoided;
once a year, with all members of the team present, to announce new developments and review policy.

Operational meetings are also held regularly to discuss organizational matters, equipment, and working protocols.