Transpupillary thermotherapy of choroidal melanoma

Abstract

A retrospective analysis of the immediate and long-term effectiveness of the treatment of the choroidal melanoma using transpupillary thermotherapy (TTT) was carried out. The study included 84 patients with choroidal melanoma (C69.3) who received treatment between 2007 and 2018. Patients were sampled from the Belarusian Cancer Register. The average values of the thickness of the tumor were 2.6±1.3 mm, the diameter of the base - 7.2±3.3 mm. TTT was carried out using a diode laser with a wavelength of 860 nm and radiation power of 200 - 800 mW, the exposure time was 60 s, and the diameter of the laser spot was varied between 1 and 3 mm. The entire surface of the tumor was thermally treated with overlapping fields from the periphery to the top. 75 patients underwent a single session of TTT, while 9 - two sessions with an interval of 3–4 weeks. As a result of the treatment, 51 (60.7%) patients showed complete tumor resorption, 28 (33.3%) patients had stabilization of the tumor process, and 5 (6.0%) patients had no effect. In the group of patients with stabilization of the tumor process, continued growth was recorded in 16 (19.1%) patients with follow-up periods of 3 months to 4 years. In 19 (37.3%) patients from the group with complete tumor regression, relapse was observed 1 to 8 years after TTT. Metastatic disease (disease progression) developed in 5 (5.9%) patients, of which in 1 patient during the first 12 months, in 1 patient - after 4 years, and in 3 patients more than after 5 years of the follow-up observation. Analysis of the effectiveness of TTT of choroidal melanoma showed that an increase in the thickness and diameter of the base of the tumor focus results in the decrease of immediate effectiveness, and the rise of the likelihood of continued tumor growth.