Purpose
To explore relationship between regression rate of ciliary/choroidal melanoma after plaque radiotherapy and percentage composition with chromosome 3 monosomy tumor cells.
Methods
One hundred fifty consecutive patients underwent fine needle aspiration biopsy at the time of plaque radiation therapy to sample tumor cells for prognostication. Fluorescence in situ hybridization (FISH) was performed to evaluate the percentage of tumor cells with chromosome 3 monosomy (200 cell count). Regression rate was calculated as percent change in tumor height (measured by ultrasonography). Relationship between regression rate and tumor location, initial tumor height, and percentage chromosome 3 monosomy was assessed by univariate linear regression at months 3, 6, and 12 following plaque radiation therapy (R version 3.1.0).
Results
Of the 150 patients, 75 patients were excluded because treatment (enucleation and resection, 48) or location of the tumor (irido ciliary, 16 ) or lack of cytological confirmation (11) of the diagnosis. At time of diagnosis the mean tumor height was was 5.15 mm (1.90-13.00mm). Percent chromosome 3 monosomy ranged from 0-20% (35) to 81-100 (10%). The percentage of tumor height at months 3, 6, and 12 did not statistically correlate with tumor location (ciliray or choroidal), initial tumor height, and percentage chromosome 3 monosomy (Figure 1).
Conclusions
Regression rate in height of uveal melanoma following brachytherapy does not correlate with the percentage composition of tumor cells with chromosome 3 monosomy.