Prognostic fine needle aspiration biopsy of uveal melanoma: Molecular and genetic factors of metastasis risk

Introduction. Molecular genetic testing is actively used for prognostication in patients with uveal melanoma (UM). Tissue for genetic analysis may be obtained either by surgical excision or through fine-needle aspiration biopsy (FNAB). Performing genetic testing and FNAB in each institution can differ in surgical techniques and laboratory methodologies. Aim. To present our own experience of performing FNAB-based molecular genetic testing for prognostication in patients with uveal melanoma. Materials and methods. Prognostic FNAB (n = 151) were combined with brachytherapy or stereotactic surgery. Genetic testing was performed by methods based on polymerase chain reaction ( GNAQ, GNA11, EIF1AX and SF3B1 mutations) and fluorescence in situ hybridization (copy numbers of PPARG and MYC genes); cytology of FNAB material was also assessed. Results. Fine-needle aspiration biopsy material was informative in 91 % of cases. At the median follow-up of 36 months, 12 cases of distant metastases were detected. Occurrence of the assessed mutations and copy numbers were related to other representative studies. PPARG deletion was shown to be a significant prognostic factor for metastasis-free survival (p <0,01), which was demonstrated for the first time; EIF1AX and SF3B1 mutations, MYC amplification and cytological class were not shown to be significantly associated with survival in our study. Conclusion. FNAB-based molecular genetic testing for prognostication in patients with uveal melanoma was shown to be a reliable and highly informative approach. Some of the prognostic factors need to be evaluated further with longer follow-up.