Assessment of the Relationship between Metabolic Activity of Uveal Melanoma in Positron Emission Tomography (PET) and Chromosome 3 Monosomy

Overview

Introduction: Uveal melanoma is the most common primary malignant intraocular tumor in adults. A major prognostic factor is the cytogenetic profile of the tumor, particularly the presence of monosomy of chromosome 3, which is associated with an increased risk of developing distant metastases. The aim of this study was to determine whether there is a relationship between the metabolic activity of the tumor assessed by SUVmax (maximum standardized uptake value) in PET/CT or PET/MRI and the presence of monosomy 3 in the tumor cytogenetic profile.

Material and Methods: A total of 37 patients with uveal melanoma were included in this retrospective analysis. All patients underwent staging wholebody PET/CT or PET/MRI with calculation of SUVmax, followed by enucleation of the affected eye and cytogenetic examination of the tumor. All patients were examined and subsequently treated between 2009 and 2024 at the Department of Ophthalmology, University Hospital Plzeň.

Results: Monosomy 3 was detected in 21 patients. In this group, SUVmax values ranged from 2.7 to 14.5 (mean 6.6; median 6.5). Metastatic dissemination occurred within 5 years of diagnosis in 16 patients (76.2%), and in an additional four patients after a longer interval. Disomy 3 was present in 16 patients, with SUVmax values ranging from 1.1 to 8.0 (mean 3.4; median 3.4). Metastatic spread occurred in only one patient (6.3%). The difference in SUVmax values between the groups was highly statistically significant (p = 0.00012).

Conclusion: Higher SUVmax values were associated with the presence of monosomy 3 and an increased risk of metastatic progression. PET/CT and PET/ MRI imaging may be beneficial not only for diagnosis and primary staging of metastatic disease, but also for indirect estimation of the tumor’s genetic variant.

Keywords:

PET/CT – PET/MRI – uveal melanoma – chromosome 3 monosomy – SUVmax