Abstract
Purpose: :
To evaluate the in vivo identification, using fine–needle aspiration biopsy, of monosomy 3 and gains of chromosome 6 in posterior uveal melanoma undergoing brachitherapy.
Methods: :
Eleven consecutive patients affected by posterior uveal melanoma (> 4.5 mm in thickness) and scheduled for Iodine–125 brachitherapy, underwent transscleral intraoperative cytologic fine–needle aspiration biopsy just before plaque implantation. Specimens underwent FISH technique to detect both chromosome 3 and 6 status.
Results: :
Minimum follow–up was 7 months (7–24 months). All tumours (11/11, 100%) gave enough material for cytogenetic analysis of both chromosomes. Seven cases (63.6%) had monosomy 3 only, two cases (18.2%) had chromosome 6 overexpression only. One case (9.1%) had both alterations, and one case (9.1%) had no chromosome 3 and 6 alterations. Cytogenetic abnormalities were not related (p>.05) to tumour dimensions and tumour location (choroid/ciliary body). No major complications or extrascleral extension were documented during follow–up. Two patients (18.2%) with monosomy 3 developed metastatic disease and died during follow up.
Conclusions: :
Intraoperative, transscleral fine–needle aspiration biopsy yields sufficient material to determine chromosome 3 and 6 alterations in posterior uveal melanoma. FISH analysis for chromosome 3 and 6 is an efficient technique to analyze fresh cytologic tumour specimens. Cytogenetic prognostication of posterior uveal melanoma may be safety performed even when a conservative therapeutic approach is performed.
Keywords: melanoma • gene/expression • fluorescent in situ hybridization