Ocular melanoma is a rare but serious cancer that develops in the eye, requiring specialized approaches to preserve vision while controlling the disease. From targeted radiation techniques to innovative therapies tested in clinical trials, treatment options continue to evolve to help patients maintain their quality of life.

Treatment Pathways for Eye Cancer: Understanding Your Options

When someone receives a diagnosis of ocular melanoma, the primary goals of treatment focus on controlling the cancer within the eye, preserving as much vision as possible, and preventing the disease from spreading to other parts of the body. The approach to treatment depends heavily on the size and location of the tumor, as well as the patient’s overall health and visual function in both eyes. Each person’s situation is unique, which means treatment plans are carefully tailored to individual circumstances.

Medical specialists have developed a range of treatment options over the years, from standard methods that have proven effective to newer approaches being studied in clinical trials. Standard treatments include radiation therapy delivered directly to the tumor, surgical removal of the affected eye in severe cases, and monitoring techniques for very small growths. At the same time, researchers are exploring innovative therapies that target specific molecular pathways involved in cancer growth, offering hope for better outcomes and fewer side effects in the future.

The treatment journey typically begins with a thorough evaluation by an ocular oncologist—a specialist in eye cancers. This evaluation includes detailed imaging studies such as ultrasound, which uses sound waves to measure the tumor’s size and shape, and optical coherence tomography, a test that provides cross-sectional images of the eye’s internal structures. These diagnostic tools help doctors determine the tumor’s characteristics and stage, which in turn guides treatment decisions.^[7]

For many patients, the emphasis is on preserving the eye and maintaining useful vision whenever possible. Small to medium-sized tumors can often be treated without removing the eye, using techniques that destroy cancer cells while minimizing damage to surrounding healthy tissue. However, larger tumors or those that have caused significant damage may require more aggressive interventions. Understanding the full spectrum of available treatments helps patients make informed decisions about their care.

Standard Treatment Approaches for Ocular Melanoma

The most common standard treatment for ocular melanoma involving the uveal tract—the middle layer of the eye that includes the iris, ciliary body, and choroid—is a form of radiation therapy called plaque brachytherapy. This technique has become the preferred approach for many patients because it can effectively treat the tumor while preserving the eye itself. During this procedure, a small disc-shaped device called a plaque is temporarily attached to the outer wall of the eye near the tumor. The plaque contains radioactive seeds that deliver a concentrated dose of radiation directly to the cancer cells over several days, typically four to seven days, after which the plaque is surgically removed.^[9]

The radiation works by damaging the DNA inside cancer cells, preventing them from dividing and growing. Because the radiation is delivered so precisely to the tumor site, it minimizes exposure to healthy parts of the eye and other organs. However, patients need to understand that this treatment can still affect vision over time. The radiation may damage the retina—the light-sensitive tissue at the back of the eye—or the optic nerve that carries visual signals to the brain, potentially leading to gradual vision loss months or years after treatment. Regular follow-up examinations are essential to monitor these effects.^[7]

Another radiation option is proton beam therapy, which uses charged particles called protons rather than traditional X-rays. Proton beams can be shaped very precisely to match the tumor’s contours, delivering maximum radiation to cancer cells while sparing surrounding tissues. This treatment is typically administered over several sessions during a period of about one to two weeks. Proton therapy requires specialized equipment available only at certain medical centers, so not all patients have easy access to this option. Like plaque brachytherapy, proton therapy aims to control the tumor while keeping the eye intact, though it also carries risks of radiation-related vision complications over time.^[9]

For very large tumors, or cases where radiation therapy is not suitable or has failed, surgical removal of the eye—a procedure called enucleation—may be necessary. While this is a difficult decision for most patients, enucleation completely removes the cancer and can be the best option when the tumor has destroyed much of the eye’s internal structure or when vision is already severely compromised. During the surgery, the eyeball is removed but the muscles and surrounding tissues are preserved. After healing, patients are fitted with a prosthetic eye that matches the appearance of the other eye, helping restore a natural look. The prosthesis does not provide vision but can move with the remaining eye muscles to appear quite natural.^[9]

In select cases, surgeons can perform a local resection, removing only the tumor and a margin of healthy tissue around it while leaving the rest of the eye intact. This approach is technically challenging and suitable only for certain tumor locations and sizes. It carries risks including bleeding, infection, and potential damage to vision, but offers an alternative to complete eye removal for carefully selected patients.

Additional therapies may be used alongside radiation or surgery. Cryotherapy, which uses extreme cold to freeze and destroy cancer cells, can be applied to small tumors or as an additional treatment during surgery. Transpupillary thermotherapy uses infrared laser light to heat and destroy tumor tissue, though it is typically used for smaller melanomas. Laser photocoagulation can also be employed in certain situations to target blood vessels feeding the tumor, cutting off its nutrient supply.^[9]

For conjunctival melanoma, which develops on the surface of the eye rather than inside it, treatment typically involves surgical removal of the visible tumor with clear margins of healthy tissue around it. Because this type of melanoma grows on the outside of the eye, surgeons can directly access and remove it. After surgery, additional treatments may include topical chemotherapy—chemotherapy medication applied directly to the eye surface as drops—such as mitomycin C or interferon. Cryotherapy may also be applied to the surgical margins to destroy any remaining abnormal cells. Unlike uveal melanoma, conjunctival melanoma can spread to lymph nodes and requires different follow-up monitoring strategies.^[3]

Treatment side effects vary depending on the approach used. Radiation therapy can cause dry eyes, inflammation, cataract formation, bleeding inside the eye, increased eye pressure (glaucoma), and progressive vision loss due to damage to the retina or optic nerve. These complications may develop months or years after treatment, requiring ongoing ophthalmologic care. Enucleation involves the psychological adjustment to losing an eye and learning to function with monocular vision, which affects depth perception and peripheral vision. Patients may experience phantom eye pain or discomfort as they adapt to the prosthesis.^[16]

Innovative Therapies Being Tested in Clinical Trials

While local treatments for the primary tumor in the eye have improved dramatically, the major challenge in ocular melanoma remains managing metastatic disease—cancer that has spread beyond the eye. Approximately 40 to 50 percent of patients with uveal melanoma will eventually develop metastases, most commonly in the liver, and this typically occurs years after the original eye tumor was successfully treated. Unfortunately, traditional chemotherapy has shown limited effectiveness for metastatic ocular melanoma, making the development of new therapies an urgent priority.^[4]

One of the most significant advances in recent years has been the development of immunotherapy drugs specifically designed for metastatic ocular melanoma. Unlike traditional chemotherapy that directly attacks cancer cells, immunotherapy works by helping the patient’s own immune system recognize and destroy cancer cells. The immune system normally patrols the body looking for abnormal cells, but cancer cells often develop ways to hide from immune surveillance. Immunotherapy drugs remove these disguises, allowing immune cells to attack the tumor.

The drug tebentafusp represents a breakthrough in this area and is currently the only FDA-approved immunotherapy specifically for metastatic uveal melanoma. Tebentafusp is a unique type of therapy called a bispecific T-cell engager, which works by simultaneously binding to both cancer cells and immune cells called T-cells, bringing them into close contact. This forces the T-cells to recognize and attack the melanoma cells. Clinical trials testing tebentafusp showed that it could extend survival time in patients with metastatic uveal melanoma compared to standard chemotherapy or other treatments available at the time. The drug is given as an intravenous infusion, starting with a carefully controlled dose escalation to minimize side effects.^[13]

Treatment with tebentafusp can cause side effects because activating the immune system affects the whole body. Common reactions include fever, chills, fatigue, rash, swelling, and nausea, particularly after the first few doses. Most patients experience these symptoms, but they typically become less severe with continued treatment as the body adapts. More serious side effects can include liver inflammation, changes in heart rhythm, and severe skin reactions, requiring careful monitoring by healthcare providers throughout treatment.

Researchers are also investigating targeted therapy approaches that focus on specific genetic mutations found in ocular melanoma cells. Unlike cutaneous (skin) melanoma, which frequently has mutations in a gene called BRAF, uveal melanoma typically has mutations in different genes—most commonly GNAQ, GNA11, BAP1, and SF3B1. Understanding these genetic differences is crucial because treatments effective for skin melanoma may not work for eye melanoma and vice versa.^[3]

Clinical trials are exploring drugs called MEK inhibitors, which block a protein involved in cell growth signaling pathways that are often abnormally activated in uveal melanoma. These drugs aim to stop cancer cells from dividing and spreading. Another approach involves targeting the protein kinase C (PKC) pathway, which is affected by mutations in GNAQ and GNA11 genes. Researchers hope that by interfering with these specific molecular pathways, they can slow tumor growth with fewer side effects than traditional chemotherapy.

For patients with liver metastases, specialized procedures can deliver treatment directly to the liver while minimizing effects on the rest of the body. Transarterial chemoembolization, or TACE, involves threading a thin tube called a catheter through blood vessels to reach the arteries feeding the liver tumors. Chemotherapy drugs are then injected directly into these arteries, along with particles that block blood flow to the tumor. This approach concentrates the chemotherapy in the liver where the metastases are located, while the blocking particles starve the tumors of oxygen and nutrients.^[13]

Another liver-directed therapy being studied is selective internal radiation therapy, or SIRT, also known as radioembolization. This technique involves injecting tiny radioactive beads into the blood vessels supplying liver tumors. The beads lodge in the small vessels within the tumors, delivering concentrated radiation directly to the cancer while sparing most of the healthy liver tissue. These procedures are performed by interventional radiologists and may be repeated if needed.

Some clinical trials are investigating combinations of different treatment approaches. For example, researchers are testing whether combining immunotherapy with targeted therapy drugs might be more effective than either approach alone. Other studies explore using liver-directed treatments alongside systemic therapies to attack metastases through multiple mechanisms simultaneously. The goal is to find combinations that work together to control cancer growth more effectively than single treatments.

Clinical trials are conducted in phases to carefully evaluate new treatments. Phase I trials primarily assess safety and determine the appropriate dose of a new drug, involving small groups of patients. Phase II trials test whether the treatment shows promise in fighting the cancer and continue to monitor safety, involving larger patient groups. Phase III trials compare the new treatment directly against the current standard treatment to determine if it offers advantages, involving hundreds of patients at multiple medical centers.^[8]

Participating in a clinical trial can give patients access to cutting-edge treatments before they become widely available. However, it also involves uncertainty, as new treatments may not work as hoped or may have unexpected side effects. Trial participants are closely monitored throughout the study, and they can typically leave the trial at any time if they choose. Eligibility requirements vary by trial, but generally depend on factors such as the stage of disease, previous treatments received, and overall health status.

Many clinical trials for ocular melanoma are conducted at specialized cancer centers with expertise in this rare disease. These centers often have multidisciplinary teams including ocular oncologists, medical oncologists, radiation oncologists, and surgical specialists who work together to provide comprehensive care. Patients interested in clinical trials can ask their doctors for referrals to such centers or search clinical trial databases to find studies that might be appropriate for their situation.

Most common treatment methods

• Radiation therapy
  • Plaque brachytherapy using radioactive seeds attached to the eye wall near the tumor for several days
  • Proton beam therapy delivering charged particles precisely targeted to the tumor
  • Selective internal radiation therapy (SIRT) for liver metastases using radioactive beads
• Surgery
  • Enucleation to remove the entire eye in cases of large tumors or failed previous treatments
  • Local tumor resection removing only the melanoma and surrounding tissue margin
  • Wide local excision for conjunctival melanoma with surgical margins
• Ablative techniques
  • Cryotherapy using extreme cold to freeze and destroy tumor cells
  • Transpupillary thermotherapy applying infrared laser heat to tumor tissue
  • Laser photocoagulation targeting blood vessels feeding the tumor
• Immunotherapy
  • Tebentafusp, a bispecific T-cell engager that brings immune cells into contact with cancer cells for metastatic disease
  • Topical interferon for conjunctival melanoma
• Targeted therapy
  • MEK inhibitors blocking abnormal cell growth signaling pathways
  • Protein kinase C pathway inhibitors targeting specific genetic mutations
• Liver-directed treatments
  • Transarterial chemoembolization (TACE) delivering chemotherapy directly to liver metastases
  • Radioembolization using radioactive beads in liver blood vessels
• Topical chemotherapy
  • Mitomycin C eye drops for conjunctival melanoma
  • Interferon drops applied to the eye surface after surgery