Photodynamic therapy for ciliary body melanoma: experience with an isolated transscleral approach

Ciliary body melanoma (CBM) accounts for up to 20% of uveal melanoma cases and presents challenges for organ-preserving treatment due to its peripheral location and proximity to critical ocular structures. This study presents the first clinical results evaluating the efficacy and safety of isolated transscleral photodynamic therapy (TSPDT) with a chlorin e6 photosensitizer in 7 patients with CBM. The procedure was performed using an «ALOD-01» laser system (λ=662 nm) and standardized irradiation parameters (energy density 519.5 J/cm², accounting for power loss during scleral transmission). The mean follow-up period was 19.0±5.9 months and demonstrated high local tumor control: complete regression was achieved in 4 patients, and partial regression in 3 patients. A statistically significant reduction in tumor height (from 4.69±2.58 mm to 1.36±1.14 mm; p=0.0062) and basal diameter (from 8.54±3.56 mm to 6.65±3.70 mm; p=0.016) was accompanied by a pronounced vasculo-occlusive effect, manifested as complete tumor avascularity in the majority of patients according to ultrasound with color Doppler Imaging (CDI). Echodenstitometry recorded a statistically significant decrease in mean acoustic density from 35.53±1.26 dB to 28.97±0.83 dB (p=0.0002), which may indicate tumor tissue destruction. No intra– or postoperative complications were recorded throughout the observation period, and a trend towards stable visual acuity was noted. The obtained data suggest that TSPDT is a promising minimally invasive organ-preserving method for treating CBM, requiring further investigation to define its role as either a standalone or combined therapy.