Abstract
Purpose :
Iris melanoma represent as little as 2% of uveal melanoma whereas iris nevi is present in 47% of patients with melanocytic iris lesion. As transformation to malignity is described, aim of the study was to analyze risk factors and course of iris lesions to elucidate a protocol as potential diagnostic tool in the clinical management.
Methods :
Retrospective chart analysis of patients with melanocytic lesions of the iris between 1999-2016 in a tertiary ophthalmic oncology centre. Ciliar body melanoma and ring melanoma have not been included in this study. Epidemiologic and ophthalmologic data at baseline and during follow-up, including best corrected visual acuity, intraocular pressure, gonioscopy and ultrasound biomicroscopy were collected. Photographs of the iris were evaluated by two independent examiners to describe morphological characteristics of the iris lesions. Related data were analyzed under the consideration of the ABCDEF-guide of Shields (A=Age young, B=Blood, C=Clock hour inferior, D=Diffuse configuration, E=Ectropion and F=Feathery margin), malign transformation over time and indication for biopsy.
Results :
500 patients with melanocytic lesions (76 %), amelanotic lesions (8,4 %), lesion of unknown origin (7,0 %) and iris melanoma (6,3 %) have been included. A biopsy was performed in 12% of the patients. Age, inferior localization of the nevus, ectropion uveae and feathery margin showed no difference between melanoma and nevus at baseline. At time of baseline, 45,3 % of the growing tumors revealed a distorted pupil and a tumor thickness > 1 mm in contrast to non-growing lesions (6,2 %). Univariate regression analysis indicated temporal or nasal-inferior localization of the iris lesion, a distorted pupil and thickness of tumor > 1 mm as predictive factors for growth. Control intervals in the melanoma-group were shorter (< 6 months) compared to nevus-group (> 6 months). Own data together with the ABCDEF-guide of Shields were reconsidered to establish a possible scheme for clinical management of iris lesions.
Conclusions :
The results of this study indicate localization and thickness as predictive factors for growth and malignant transformation. We presume that adjusted control intervals could be useful in the clinical management of iris lesions. Prospective studies are necessary to precise existing clinical control intervals.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.