Photodynamic Therapy for Choroidal Melanoma and Other Eye Tumors

Photodynamic therapy for choroidal melanoma and other eye tumors works with light rather than radiation. A drug that reacts to light is infused into a vein; while it circulates through the tumor's blood vessels, a laser beam of a specific red wavelength is shone onto the tumor through the pupil. The activated drug damages the lining of the vessels, which close off, and the tumor loses its blood supply.

PDT is well established for some benign tumors and is used selectively for small uveal melanomas. Prof. Türkoğlu's own published research is summarized below, alongside evidence from other centers, together with thermotherapy, laser photocoagulation and the investigational drug bel-sar.

How does photodynamic therapy work?

PDT has two parts. Verteporfin, a light-sensitive drug, is given as a slow infusion into a vein, with the dose calculated from body surface area (the standard dose is 6 mg per square meter). Laser light of 689–690 nm is then applied to the tumor through a contact lens for a set time — 83 seconds in the standard protocol — with a light spot sized to cover the tumor.

The activated drug releases reactive oxygen molecules that injure the cells lining the abnormal vessels. The vessels close, fluid stops leaking, and tumor tissue that depends on them can die off. Because the light neither heats nor irradiates the eye, the surrounding retina is largely spared. For a short period afterward, the skin and eyes are sensitive to strong light, so patients avoid direct sunlight and bright light for the time the team specifies.

When is photodynamic therapy used for choroidal melanoma?

For small melanomas, the standard eye-preserving treatment is radiation, usually plaque brachytherapy. PDT is an alternative that avoids radiation for selected small tumors, and it has also been used as an add-on after stereotactic radiotherapy (see the research section below).

The evidence comes from small series. At Moorfields Eye Hospital in London, 26 patients with small pigmented melanomas at the back of the eye received PDT as their primary treatment. The tumor was controlled in 62%; estimated success was 85% at 1 year, 59% at 2 years and 51% at 3 years. Failures usually occurred through sideways growth at the tumor's edge, after a median of 13 months, and vision improved in patients whose tumors were controlled.

Because tumors can regrow, PDT alone is not generally recommended as a routine treatment for melanoma, and close follow-up with imaging is essential. Some specialists consider non-pigmented (amelanotic) tumors more responsive, because pigment absorbs part of the light, but this has not been firmly established. How a nevus is told apart from an early melanoma is explained on the choroidal nevus page.

Which other eye tumors can be treated with PDT?

Choroidal hemangioma. For a circumscribed choroidal hemangioma — a benign, orange-red tumor of blood vessels — that causes fluid and blurred vision, PDT is the treatment of choice. The tumor usually flattens and the fluid resolves within about 3 months, with a lasting effect in most patients. In a series of 10 patients treated with standard settings, every tumor regressed and the fluid cleared in all; vision was stable or better in 80%, but 2 patients lost vision from later thinning of the treated tissue (choroidal atrophy). The diffuse type seen in Sturge-Weber syndrome can also be treated with PDT. See choroidal hemangioma.

Choroidal metastasis. Small metastases at the back of the eye can be treated with PDT, which often improves vision when fluid is present. See choroidal metastasis.

Other benign tumors. Retinal hemangioblastomas (for example in von Hippel-Lindau disease) and vasoproliferative tumors may be treated with PDT among other options. See benign intraocular tumors.

What happens during a PDT session?

1. Imaging and planning. Photographs, ultrasound, OCT and often angiography document the tumor and any fluid, and determine the size of the light spot.
2. Preparation. The pupil is dilated, and your height and weight are used to calculate the drug dose.
3. Infusion. Verteporfin is given slowly into a vein in the arm.
4. Light treatment. After numbing drops, a contact lens is placed on the eye and the laser light is applied for the set time. This is usually not painful.
5. Going home. PDT is an outpatient treatment; you leave with advice on protecting your skin and eyes from strong light.
6. Checking the response. Imaging after a few months shows whether the tumor has responded; some tumors need a further session.

What has Prof. Türkoğlu's research on PDT shown?

Prof. Türkoğlu has contributed to three published studies on photodynamic therapy for eye tumors, two of them as first author.

How to read these results. All three studies are small, as is usual for rare tumors. With reports from other centers, they support PDT as an effective treatment for choroidal hemangioma and as a carefully selected, closely monitored option for some small melanomas — alone or combined with radiotherapy.

What are the risks and limitations of PDT?

• Regrowth of melanoma is the main limitation: at Moorfields, about half of tumors remained controlled at 3 years. Regular imaging is essential, and radiation remains available if a tumor grows.
• Thinning of the treated tissue (choroidal atrophy) can reduce vision, as in 2 of the 10 hemangioma patients described above.
• Tumor size: PDT is used for small, relatively flat tumors; thicker melanomas need radiation.

What are transpupillary thermotherapy and laser photocoagulation?

Both deliver laser energy through the pupil, but they heat or coagulate tissue instead of activating a drug.

Transpupillary thermotherapy uses an 810-nm infrared diode laser to warm the tumor to about 45–60 °C. Small melanomas regress in about 92% of cases, but about one in three recurs when TTT is used alone, more often next to the optic disc, so it is now used mainly as an add-on to plaque brachytherapy ("sandwich" therapy).

Laser photocoagulation treats small retinal hemangioblastomas, up to about 1.5–2 mm, usually in sessions repeated every 4–6 weeks. In retinoblastoma, laser, thermotherapy and freezing (cryotherapy) treat small tumors and consolidate the effect of chemotherapy.

What is bel-sar, and can I receive it?

Bel-sar (belzupacap sarotalocan, AU-011) is an investigational light-activated drug developed by Aura Biosciences for early choroidal melanoma. The developer describes it as a virus-like particle carrying a light-sensitive molecule that binds to tumor cells; it is injected into the suprachoroidal space (between the eye wall and the choroid) and activated with a near-infrared laser.

The phase 3 CoMpass trial (NCT06007690) compares two dose levels of bel-sar with a sham (simulated) treatment in previously untreated patients with an indeterminate lesion or a small choroidal melanoma with documented growth; its main measure is the time until the tumor progresses, over about 15 months. Enrollment of 108 patients at more than 70 sites in 15 countries was completed on 1 June 2026, and results are expected in the second half of 2027. Bel-sar has US Fast Track status and orphan designation in the US and the EU.

Photodynamic therapy and eye tumor care in Antalya

Prof. Türkoğlu has published clinical research on photodynamic therapy for choroidal melanoma, choroidal hemangioma and other intraocular tumors. At a consultation she reviews the imaging, explains whether PDT, radiation, observation or another approach suits your tumor, and plans treatment and follow-up with you; where a method needs specialized facilities, it is delivered together with the relevant specialist teams. Patients abroad can start with a remote second opinion based on their photographs, ultrasound and OCT scans.