Abstract
Purpose :
Uveal melanomas (UM) can be divided into prognostic groups based on gene expression profile (GEP) class 1 versus class 2, class 1A versus 1B, and preferentially expressed antigen in melanoma (PRAME) - versus PRAME+. The purpose of this study was to evaluate gthese factors in young patients.
Methods :
1756 patients from 26 centers were enrolled into COOG2 prospective study, all patients had tumor biopsy for genetic analysis. We analyzed clinical and genetic data from 76 patients 18-35 years of age and excluded 7 primary iris lesions resulting in 69 analyzed patients.
Results :
A total of 69 patients between 18-35 years were analyzed. Average age was 30 years, with 35 female and 34 male.
3 patients had ocular melanocytosis. 9 tumors involved ciliary body. Largest basal diameter varied from 3 to19.3mm (mean11.5 mm) and tumor thickness 1.2-15.3 mm (mean 5.1 mm).
Primary treatment was brachytherapy with radioactive iodine (I-125) in 56 patients, enucleation 8 in eyes, proton beam therapy in 4 patients and observation in 1 patient. All patients underwent tumor biopsy (transscleral 18 patients, transvitreal 43 and enucleation 8 patients). GEP analysis revealed Class 1A (31 tumors, of them 10 PRAME +), followed by Class1B (27, of them 7 PRAME +) and Class 2 (10 tumors, of them 3 PRAME +).
Follow-up period is 1-56 months (average 19 months). No tumor recurrence was documented. Metastatic disease developed in 1 patient with Class 1A PRAME + large tumor (16 months after treatment, patient died at 37 months follow up).
Conclusions :
Most young patients with UM have genomic profile consistent with very favorable prognosis (Class 1A PRAME -), even when they have clinical features that are considered to be high risk. This suggests that endogenous factors, such as immune regulation, may favor the evolution of less aggressive molecular subtypes of UM in younger patients. Further investigation and longer follow up is warranted to elucidate the biological factors in young patients that predispose them to better survival prognosis.
This is a 2021 ARVO Annual Meeting abstract.