Abstract
Purpose :
According to the literature, 1-6% of the uveal melanoma (UM) patients have a family history of UM, which is higher than predicted to occur by chance alone. In about 22% of these families, an underlying BAP1-tumour predisposition syndrome (BAP1-TPDS) is found. These patients carry a germline mutation in the BAP1-gene and have an increased risk for developing UM, cutaneous melanoma (CM), malignant mesothelioma (MMe), and renal cell carcinoma (RCC). Here we evaluate the clinical, tumour, and family characteristics of patients seen at the LUMC, Leiden, The Netherlands, who were referred to the geneticist for analysis of BAP1.
Methods :
Since 2017, questionnaires regarding the family history of the patient are given to UM patients at the Leiden University Medical Center. Patients who are considered at risk for BAP1-TPDS, based on their medical history or family history, are referred to the clinical geneticist for analysis. Clinical, tumour, and family characteristics of the UM patients were collected.
Results :
291 questionnaires were analysed, and 66 UM patients (23%) were referred to the clinical geneticist. Nine patients who were eligible for referral declined genetic analysis. The cause for referral was family history in 44 patients, personal medical history in 10 patients, and age at diagnosis for 12 patients. Personal or family history of referred patients included UM, CM, MMe, and RCC for 10, 3, 2, and 7 patients, respectively. Genetic analysis of germline BAP1 has been completed of 27 cases and no cases of BAP1-TPDS were found. UM was localised in the choroid for 54 patients (80%), while four had ciliary body UM (6%), and eight had iris melanoma (12%). The mean age is 56 years (±17). 51 patients were treated by ruthenium brachytherapy, 8 were enucleated, and proton beam therapy was used in 6 cases. One iris melanoma was excised. The mean largest basal diameter of referred patients with choroidal or ciliary body melanoma was 12 mm (±3), while the mean prominence was 5 mm (±3). BAP1 staining was negative in 3 of the 6 UM cases (50%).
Conclusions :
We have described the clinical, tumour, and family characteristics of patients referred for analysis of BAP1-TPDS. As expected, referred patients are young and most have a personal or family history of UM, CM, MMe and/or RCC. We have not yet identified a UM patient harbouring BAP1-TPDS.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.