[Correlation between ICG angiography verified networks in uveal melanomas and rate of tumor regression after brachytherapy].
BACKGROUND
The post-irradiation regression rate of uveal melanomas is a prognostically significant factor for the development of metastases. Other predictive factors for metastases are histological networks which are imagable with confocal ICG angiography. The purpose of this study was to evaluate a possible connection of networks in the ICGA and tumor regression rates.


METHODS
We compared the post-irradiation regression rates (as %) in 20 patients 1 year after brachytherapy with networks identified in pre-treatment indocyanine green angiography (ICGA). The ICG angiography was performed before irradiation, 10 patients were irradiated with Ru-106 and 10 were irradiated with Id-125.


RESULTS
The mean preoperative maximum apical height was 5.2 mm [SD: 1.5 mm; Ru106 group: 5.7 mm (SD: 1.0 mm); Id-125 group: 5.0 mm (SD: 1.9 mm)]. In 11 patients (55%) (Ru-106: 5; Id-125: 6) we found networks in the preoperative ICG. The mean regression rate in tumors with networks was 51.3% (SD: 14.7%) and 28.0% (SD: 16.4%) in the group without networks. The difference between both groups was statistically significant (p = 0.003, Mann-Whitney test). No statistically significant difference in the regression rates was found between the two groups of brachytherapy Ru-106 and Id-125 (p = 0.165, Mann-Whitney test).


CONCLUSIONS
Highly proliferative tumors are known to be more sensitive to irradiation. This may be one reason why tumors with a rapid post-irradiation regression are the more aggressive ones with regard to later development of metastases. Histopathological networks are also known to be a strong indication of more aggressive, metastasizing tumors. These networks are also imagable in ICG angiography. Our observation emphasizes a connection between networks in ICG angiography and regression rates of uveal melanomas after brachytherapy.
Schaller
U C
UC
Augenklinik der Ludwig-Maximilians-Universität, Mathildenstrasse 8, 80336 München. Ulrich.Schaller@ak-i.med.uni-muenchen.de
Mueller
A J
AJ
Bartsch
D U
DU
Schaumberger
M
M
Freeman
W R
WR
Kampik
A
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy; D005260:Female; D005451:Fluorescein Angiography / Q000379:methods*; D006801:Humans; D007208:Indocyanine Green; D008297:Male; D008545:Melanoma / Q000098:blood supply* / Q000532:radiotherapy; D008833:Microcirculation / Q000528:radiation effects; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000175:diagnosis* / Q000532:radiotherapy; D011379:Prognosis; D016896:Treatment Outcome; D014604:Uveal Neoplasms / Q000098:blood supply* / Q000532:radiotherapy
D007208:Indocyanine Green