[Tumor regression and visual outcome after transpupillary thermotherapy (TTT) for malignant choroidal melanoma]

The aim of this study was to evaluate the course of tumor regression and visual impairment in choroidal melanomas treated by transpupillary thermotherapy (TTT) alone.

In a prospective, non-randomized analysis 26 patients suffering from primary choroidal melanoma (posterior to the equator with base < or = 12 and thickness < or = 4.5 mm) were treated with the TTT standard protocol and followed for 33 - 45 months. Fluorescein and ICG angiographies were performed initially and after tumor regression clinically.

22 tumors were significantly flattened after 1 - 3 TTT sessions. 4 tumors required additional therapy with ruthenium plaque. Visual acuity remained unchanged or improved in 11 eyes. In all eyes fluorescein and indocyanine green angiography revealed a sharp demarcation of the heat-treated area. Except for macular edema and gliosis in 6 eyes no vascular or retinal tissue damage was noticed outside the treatment zone. In the periphery of the treatment zone all eyes showed residual choriocapillaries remaining perfused. During follow-up 2 eyes revealed tumor regrowth at the posterior margin of the scar, which was successfully managed by TTT or a ruthenium plaque. 2 eyes developed late choroidal neovascularizations (CNV) in the heat-treated area. One patient died of liver metastases.

Fluorescein and indocyanine green angiographic findings after TTT for small choroidal melanomas suggest that the tissue damage in the choroidal layer is less effective, which perhaps can lead to a higher rate of tumor regrowth. Development of choroidal neovascularization may be a sign of late heat-induced side effects of TTT.