Abstract
Purpose :
Fine needle aspiration biopsy (FNAB) is a well-established technique for molecular prognostication of uveal melanoma. However, transscleral or transvitreal FNAB of very small melanomas 2 mm or less in thickness has been associated with a low biopsy yield. This report describes our center’s experience using a 27-gauge vitreous cutter to perform tumor sampling in these small melanomas.
Methods :
This was a retrospective analysis of all patients who underwent a 27-gauge vitreous cutter biopsy for molecular prognostication at the time of iodine-125 plaque placement for local treatment of choroidal melanoma. Baseline patient demographics, tumor characteristics, and biopsy results for cytopathology, cytogenetics, and gene expression profiling were reviewed.
Results :
Sixteen consecutive patients with a median follow-up time of 3.8 months (range, 0.5 – 12.4 months) were included in this study. The mean baseline tumor height was 1.71 mm (range, 1.31 – 2.18 mm) and the mean largest basal diameter was 8.9 mm (range, 5.4 – 14.9 mm). 27-gauge biopsy yielded sufficient material for cytopathology, cytogenetics, or gene expression profiling in 16/16 (100%) cases using an average of two passes with the cutter to collect biopsy material. Only certain molecular diagnostic tests were ordered for each patient as determined by the amount of biopsy material and the cost of the testing. Multiplex ligation-dependent probe amplification analysis of the samples revealed monosomy 3 in 4/10 (40%) cases. Gene expression profiling revealed class 1A status in 9/13 (69%) tumors, class 1B in 2/13 (15%), and class 2 in 2/13 (15%). Focal vitreous hemorrhage over the tumor occurred in 11/16 (69%) eyes and diffuse vitreous hemorrhage occurred in 1 case (6.3%); all hemorrhages resolved by one month with observation only. There was no instance of retinal detachment or choroidal hemorrhage associated with the biopsy.
Conclusions :
Tumor sampling of very small uveal melanomas with a 27-gauge vitreous cutter is a safe technique that offers excellent biopsy yield for molecular prognostication when cancer prognosis is desired in patients with very small choroidal melanoma.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.