K 102Influence of networks in the ICG angiography on post irradiation egression rate of uveal melanomas
U. C. Schaller1, A. J. Mueller1, D.-U. Bartsch2, W. R. Freeman2, A. Kampik1
Introduction: The post irradiation regression rate of uveal melanomas is prognostically significant factor for the developement of metastases (Augsburger: Ophthalmology (1987) 94:1173-1177). Other predicting factors for metastases are histologic networks (Folberg: Ophthalmology; (1993) 100:1389-1398). We could already demonstrate that this histologic pattern are imageable with confocal ICG-angiography (Mueller: Graefe´s Arch Clin Exp Ophthalmol (1999) 237:448-456). Purpose of this study was to evaluate the influence of networks in the ICG on tumor regression rate.
Methods: We compared the post irradiation regression rate in percent in 20 patients one year after brachytherapy with networks in the indocyanine green angiography/ICGA and maximum apical tumor hight. The ICG angiography was performed before irradiation. 10 patient were irradiated with Ru-106 and 10 were irradiated with Id-125.
Results: The mean of maximum apical hight was 5.2 mm (Std Dev: 1.54; Ru-106: 5.6 mm (Std Dev: 0.96); Iod-125: 4.8 mm (Std Dev: 1.89)). In 11 (55%) patients (Ru-106: 5; Id-125: 6) we found networks in the preoperative ICG. The mean of the regression rate in tumors with networks was 51.3% (Std Dev: 14.71%) and 28.02% (Std Dev: 16.4%) in the group without networks. The difference between both groups was statistically significant (p=0.0036, student t-Test). There was no statistically significant difference of regression rate between the two groups of Ru-106 and Id-125 (p=0.079, student t-Test).
Discussion: Highly proliferative tumors are known to be more sensible for irradiation. This may be one reason that tumors with a rapid post-irradiation regression are the more agressive ones regarding later developement of metastases. Also networks are known as a strong sign for more agressive, metastasizing tumors. Our observation emphasize the prognostic value of networks in the ICGA to assess the risk for developing systemic metastatic disease. None
1Department of Ophthalmology, Ludwig-Maximilians-Universität, Mathildenstr. 8, 80336 Munich, Germany