Background/aim: This is a long-term follow-up report investigating primary TTT for choroidal melanoma.
Methods: Retrospective case series of 135 patients harboring choroidal melanoma treated with primary TTT. Patient demographics, tumor characteristics, treatment responses and complications, visual acuity outcomes, and mortality data were captured and reported. Statistical analysis was performed for predictors of treatment failure.
Results: Successful tumor regression was achieved in 76% of patients. Of the 32 patients that failed, 12 had enucleation, and 20 had irradiation. Metastatic disease has occurred in three patients, two patients have died (3/135, or 2%). Multivariate analysis determined that tumor diameter, tumor thickness greater than 3 mm and tumors exhibiting high risk characteristics were significant predictors of failure. Patient age, gender, number of treatments, and proximity of the tumor to the disc or fovea were not predictive of failure. Kaplan-Meier cumulative probability predicted a 19% 5-year treatment failure, and 33% 10-year treatment failure. Treatment failure occurred as late as 118 months. Final visual acuity was 20/40 or better in 50% of patients; 32% had a final visual acuity of 20/200 or worse. Thirty-two percent of patients developed one or more complications as a result of the TTT, the most concerning of which was intra- or extrascleral extension of tumor (occurring in 11 patients).
Conclusions: Though not as successful as radiation therapy, TTT successfully induced regression in 76% of patients. TTT may still have a role in our treatment paradigm but should probably be reserved for specific cases, such as monocular patients with tumors near critical visual structures, surgically unstable patients, or patients with advanced diabetic retinopathy. All patients considering TTT as monotherapy for choroidal melanoma must be selected, counseled and followed appropriately.