Treatment for Eye Cancer

Executive Summary

Treatment recommendations depend upon the size, grade and type of tumor, metastasis, possible side effects, and patient’s preferences and overall health. The common treatment for eye cancer involves active surveillance, surgery (Iridectomy, Iridocyclectomy, Sclerouvectomy/endoresection, and Enucleation), removal of the eye and replacement by artificial eye (prosthesis), radiation therapy (external-beam radiation therapy, brachytherapy, proton therapy), and laser therapy (thermotherapy or transpupillary thermotherapy (TTT)). Treatment of eye cancer is done as per the stages. The common treatment used depending on the type and stage of eye cancer includes Active surveillance/observation, surgery (iridectomy), radiation therapy (proton therapy or brachytherapy), and enucleation for Iris melanoma; active surveillance/observation, radiation therapy (proton therapy or brachytherapy), laser therapy, surgical resection (removal of the tumor) or Enucleation for small choroidal or ciliary body tumor; radiation therapy (brachytherapy or proton therapy) and enucleation for medium-sized ciliary body and choroidal melanoma; Enucleation for large choroidal or ciliary body tumor; removal of the eye for extraocular extension melanoma; enrolling in a clinical trial for metastatic intraocular melanoma. Palliative care includes medication, nutritional changes, emotional and spiritual support and other relaxation therapies.

Treatment of Eye Cancer

“Standard to care” refers to the best-known treatment. In cancer care, different doctors work together to bring out an overall treatment plan for the eye cancer patient. This is called a multidisciplinary team. 

Treatment options for eye cancer and recommendations usually depend on several factors, including the type, stage and grade of cancer, possible side effects, and patient preferences and overall health.

The main target for treating intraocular melanoma is to reduce the risk of the tumor spreading and maintain the vision and health of the patient’s eye, if possible.

Active surveillance

The doctor may suggest this approach if the intraocular melanoma is small or slow-growing, or treating cancer would cause greater discomfort than the disease itself. For instance, this approach may be appropriate for people without any symptoms, older or seriously ill people, or people with a tumor in their only helpful eye.

The patient is monitored sharply, and active treatment for eye cancer starts if the tumor signs become aggressive or spread ^​1​. This approach may be called observation, watch-and-wait or watchful waiting. If the tumor grows more significant than 10 mm in diameter or 2 mm to 3 mm in height (thickness), the doctor and the patient decide to proceed with active treatment.

Surgery for eye cancer

Surgery is the removal of a tumor and surrounding healthy tissue during an operation. This is also called surgical resection. An ophthalmologist typically performs eye surgery. Surgery to the eye is very common for intraocular melanoma or eye cancer treatment. During surgery, the ophthalmologist removes parts or all of the affected eye depending on the size and spread of the tumor.

Surgical options are ^​2​–

• Iridectomy – Removal of part of the iris
• Iridocyclectomy- Removal of part of the iris and ciliary body
• Sclerouvectomy/endoresection- Surgery to remove the choroidal tumour while keeping the eye
• Enucleation – Removal of the eye

In a few cases, surgery may be used to place a radioactive disc for internal radiation therapy, known as brachytherapy. 

The possible side effects of eye surgery are similar to any surgery, including a risk of infection, problems from general anaesthesia, and pain. There is a small risk that the tumor could come back in orbit with total eye removal.

Many patients want to know whether the surgery was successful immediately. However, the success of an operation is usually hard to tell right away. It may take months before the doctors can find if all cancer cells were removed during surgery.

Having an eye removed

Sometimes, a doctor’s only choice in treating intraocular melanoma is to remove the eye. A person with one eye can have trouble with depth perception because of vision loss. Most patients adjust to the differences.

Many people get tensed about what they will look like when an eye is removed. The cosmetic surgery available usually yields good cosmetic results. The person is fitted for an artificial eye (prosthesis) to fill the area left by the missing eye. The prosthesis will behave and look almost the same as a natural eye. For instance, the artificial eye will move with the person’s other eye, just not as the natural eye moves. 

If enucleation is required, talk to the doctor about a prosthesis as early as possible. It may take many weeks to receive one. 

Radiation therapy

A doctor specializing in giving radiation therapy to treat cancer is a radiation oncologist. A radiation therapy schedule consists typically of a specific number of treatments offered over a set period.

The most common radiation treatment type is external-beam radiation therapy, in which radiation is given from the machine outside the body ^​3​. Traditional external-beam radiation therapy can be given after enucleation or palliative treatment.

Internal radiation therapy or brachytherapy is when radiation treatment is given using implants.

The ophthalmologist places a radioactive disc near the tumor for this treatment, sometimes called a plaque.

Proton therapy is an external-beam radiation therapy that uses a proton particle rather than an x-ray. Proton therapy does not go entirely through the body (and does not have an “exit dose”), so it may cause minor damage to healthy tissue.

Using radiation therapy to treat the tumor may result in vision loss or other complications so that doctors may suggest other treatments first. Also, treatment for eye cancer using radiation therapy is improving. Talk to the doctor about the benefits and risks of the different types of radiation therapy.

Radiation therapy may result in various side effects, so talking with your ophthalmologist about what to expect is essential. The extent of side effects depends on the person’s dose and type of radiation therapy, the tumor’s location, and the patient’s general health. There is more risk of radiation therapy’s side effects or complications for larger tumors. The side effects may not show up immediately. So let your doctor know if a problem arises. After being treated with radiation therapy, be sure to ask what issues and signs to watch out for.

Common side effects are –

• Cataracts – A cataract is when the lens of the eye turns cloudy. People with cataracts may have foggy or cloudy vision, have trouble seeing at night, or have problems with glare from the sun or bright lights. If the cataract is causing significant problems with a person’s eyesight, it may be surgically removed.
• Loss of eyelashes or a dry eye –These side effects can occur with proton-beam radiation therapy and external-beam radiation therapy.

The below-mentioned side effects are less common and can cause a loss of vision –

• Radiation retinopathy – The development of abnormal blood vessels in the retina
• Radiation optic neuropathy – Optic nerve damage
• Neovascular glaucoma – A painful condition where new blood vessels develop and block the outflow of fluid from the eye
• Loss of eye – If there is significant damage to the eye from radiation therapy, the eye may need to be removed.

Laser therapy

This procedure uses heat as a laser to shrink a smaller tumor. It may be called thermotherapy or transpupillary thermotherapy (TTT). This eye cancer treatment possibly has fewer side effects than surgery or radiation therapy. Laser therapy can also be combined with radiation therapy ^​4​.

Treatment by disease and stage of eye cancer

Below are the common treatments used depending on the type and stage of eye cancer. 

• Iris melanoma

Iris melanoma is not generally actively treated unless the tumor begins to grow, although there can be exceptions. The following are examples of standard treatment options:

• Active surveillance/observation
• Surgery—iridectomy
• Radiation therapy (proton therapy or brachytherapy)
• Enucleation, if the tumor is too large to remove or it spreads beyond the eye
• Small choroidal and ciliary body tumor ^​5​

The following are some eye cancer treatment options for a small choroidal or ciliary body tumor:

• Active surveillance/observation
• Radiation therapy (proton therapy or brachytherapy)
• Laser therapy
• Surgical resection (removal of the tumour) or enucleation

Careful observation is a typical treatment plan, although patients and their doctors may choose another option depending upon the tumor’s location or whether the tumor begins to grow.

• Medium choroidal and ciliary body tumour

The two most common eye cancer treatment options for medium-sized ciliary body and choroidal melanoma are radiation therapy (brachytherapy or proton therapy) and enucleation. It is supposed that there is no difference in survival rates between these two treatment methods for a medium-sized choroidal tumor.

Other treatment options for a medium-sized tumour may include surgery to remove the tumour or to enrol in a clinical trial.

Additionally, the combination of laser therapy and radiation therapy (sometimes called “sandwich therapy”) is being used more frequently to treat this type of tumour.

• Large choroidal and ciliary body tumour

For a large tumor, enucleation is the usual treatment. The Collaborative Ocular Melanoma Study (COMS) results showed that patients had similar survival rates whether they received radiation therapy before enucleation or had their eyes removed with no prior radiation treatment. Enrolling in a clinical trial can be another option for people with large choroidal and ciliary body tumors, as is additional brachytherapy.

• Extraocular extension melanoma

If the tumor has spread outside of the eye, optic nerve, or eye socket, the doctor may recommend removing the eye. Or, the doctor may perform a modified enucleation, which removes the eyeball and adjacent structures. In some cases, the doctor may remove the entire eye and the adjacent structures in an exenteration process. If the spread is small, some doctors may try to save the eye by removing the outer part of the tumor and treating the eye with radiation therapy.

Talk to the doctor about possible treatment options, potential side effects, and clinical trials open to you before choosing a treatment plan.

• Metastatic intraocular melanoma

If cancer has spread to distant parts of the body, it is known as metastatic cancer. For instance, metastatic intraocular melanoma can spread from the eye to other body parts, like the liver. Patients with this diagnosis are advised to talk with doctors experienced in treating this cancer stage because there can be various opinions about the best eye cancer treatment plan.

The health care team can suggest a treatment plan that involves treating the disease in the organ affected or enrolling in a clinical trial. Palliative care is also essential to help relieve symptoms and side effects. Patients with intraocular melanoma need to find a doctor familiar with it because it can be different from metastatic melanoma of the skin.

Palliative Care for eye cancer treatment

Cancer and its treatment have side effects that can be mental, physical or financial and managing the effects are palliative or supportive care.

Palliative care includes medication, nutritional changes, emotional and spiritual support and other relaxation therapies. 

Palliative care focuses on alleviating how you feel during eye cancer treatment by managing symptoms and supporting patients and their families with other non-medical needs. Regardless of type and stage of Cancer age, any person may receive this type of care.

Remission and the chance of recurrence

When cancer can’t be detected in the body and there are no symptoms, this is known as remission. This may also be known as having ‘no evidence of disease’ or ‘NED.’

A remission may be temporary or permanent. Many people worry about the recurrence of cancer.

If treatment doesn’t work

Recovery from bone sarcoma is not always possible. If cancer can’t be treated or controlled, it leads to advanced or terminal cancer. It is vital to have straightforward conversations with your health care team to express your feelings, preferences, and concerns. The health care team has unique skills, knowledge, and experience to assist patients and their families. Ensuring that a person is physically comfortable, free from pain, and emotionally supported is extremely important. 

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