Safety and outcome of transscleral fine-needle aspiration biopsy in uveal melanoma: 10-year experience in 347 cases

PURPOSE: To report safety outcomes of transscleral fine-needle aspiration biopsy (FNAB) followed by irradiation for uveal melanoma (UM) in a tertiary ocular oncology center over 10 years, and assess whether FNAB modified the overall prognosis of patients treated for primary UM. METHODS: Patients treated for UM between 2009 and 2020, eligible for conservative treatments by proton beam radiotherapy or Iodine-125 brachytherapy and to FNAB performed prior to UM treatment (tumor thickness 5-10 mm), were included retrospectively. Patients who underwent FNAB were compared to non-biopsied UM controls with similar characteristics, matched 1:1 using a propensity score. Complication rates, including local intraocular and extraocular relapse; metastases; and overall survival, were analyzed. RESULTS: Among 2,813 UM cases, 347 cases who underwent FNAB were matched to 347 controls. Median follow-up was 6.1 years (min=0.2-max=13.3). There was no difference in overall survival (OS) (p=0.25) and metastasis-free interval (MFI, p=0.68). Twenty-four cases (6.9%) and seventeen controls (4.9%) developed local intraocular recurrence (p=0.46). Extraocular relapses occurred in five cases (1.4%) and one control (0.3%), showing no statistical difference (p=0.12). Patients with monosomy 3 and chromosome 8 gain had significantly worse OS and MFI compared to those with normal 3 and 8 chromosomes, and to a lesser extent to those with either chromosomal alteration (p<0.0001). Those with monosomy 3 and chromosome 8 gain experienced more local recurrences (p=0.013). CONCLUSION: FNAB appears safe in terms of extraocular relapses, OS or MFI, but over the 2009-2020 period, accessing to primary UM somatic genetic features did not improve patient prognosis.