Pathogenetic mechanisms and treatment options for ophthalmic pterygium: trends and perspectives (Review)

Pterygium is a fibrovascular lesion of the ocular surface that can display an aggressive clinical behavior and, occasionally, threaten vision. Although there is no consensus on its pathogenesis, recent evidence suggests that it is a proliferative, rather than degenerative condition strongly correlated with exposure to ultraviolet radiation (UVR) of solar light. Molecular genetic alterations reported in association with pterygium include loss of heterozygosity (LOH), point mutations of proto-oncogenes, such as K-ras and alterations in the expression of tumor suppressor genes, such as p53 or p63. Other findings in pterygium include the frequent detection of HPV DNA, ocular surface changes such as the overexpression of various proteins, including defensins and phospolipases D, as well as the up-regulation of growth factors, such as bFGF or VEGF. Although pterygium management has traditionally involved surgery, often enhanced by the use of antimetabolites, recent advancements in the understanding of molecular and biochemical events underlying pterygium pathogenesis may enable the use of less invasive treatment methods.