Tumor Size Determines Treatment Modality in Uveal Melanoma

A mix of treatment modalities was assessed in a recent study that looked at patients with uveal melanoma. Of the 37 patients enrolled in the trial, patients were treated with either brachytherapy alone (19%), brachytherapy plaque with vitrectomy and silicone oil for radiation attenuation (73%), or enucleation (8%).

Study author Tara A. McCannel, MD, PhD, discussed why the choice was made to use the 3 different modalities. Most importantly, this decision was based on the tumor size. If it was less than 1 mm, patients received brachytherapy. If it was 2 mm or larger, they were given a brachytherapy plaque with vitrectomy and silicone oil. If the tumor was even larger, enucleation was considered.

In a conversation with CancerNetwork®, McCannel, director of the Ophthalmic Oncology Center at the University of California, Los Angeles (UCLA) Stein Eye Institute of the David Geffen School of Medicine at UCLA, noted that the cohort had a wide range of tumor sizes.

Transcript:

In the study, there were 3 treatments that all these patients had. One was the vitrectomy silicone oil with brachytherapy. The next group was patients who had just received brachytherapy alone. The third group, which was much smaller, was people who had their eye removed in a procedure called enucleation.

If your tumor was greater than 2 mm in thickness, you had the vitrectomy and silicone oil. If the tumor was very small, we didn’t offer the silicone oil and vitrectomy because patients tend to do very well from a visual standpoint when their tumors are very small. In addition, when the tumors are very small, the risk of the cancer spreading and developing metastasis is also small because size is important in this cancer. The reason we decided on those treatments was based on patient parameters that we had been following for some time. [Most] of this cohort had had the vitrectomy and silicone oil. With this study population that we reported on, there was a wide range of tumor sizes. It wasn’t just people [who had] small [tumors] who would do well anyway. We had a lot of people with very large tumors who underwent this procedure. We had a good mix across the board [for] types of melanomas for this [study].

Reference

Rivas A, Samlowski W, McCannel TA. Unexpectedly low rate of metastasis and death among patients treated for uveal melanoma with brachytherapy, vitrectomy, and silicone oil. Cancers (Basel). 2025;17(16):2683. doi:10.3390/cancers17162683