BRAF mutations were more frequent in males, in young patients, and in tumours with a sun-exposed tumour location (bulbar conjunctiva or caruncle), with a mixed or non-pigmented colour, with absence of primary acquired melanosis, and with origin in a nevus.
BRAF mutations were identified in 19 of 47 primary CMs (40.4%) and were more frequent in younger patients (P = .005), less frequent in the extrabulbar conjunctiva (P = .05), more frequently classified as T1 tumors (P = .03), and rarely manifested with primary acquired melanosis (P = .001) or with a uniformly pigmented lesion (P = .006).
Immunohistochemical analysis showed that EZH2 protein expression was absent in normal conjunctival melanocytes and primary acquired melanosis, while EZH2 was highly expressed in 13 (50%) of 26 primary CM and seven (88%) of eight lymph node metastases.