The traditional view of pterygium is that it is a chronic inflammatory lesion, a degenerative inflammatory lesion caused primarily by exposure to ultraviolet light. Therefore, surgery is often chosen for aesthetic reasons or because of factors such as loss of vision due to excessive invasion of the pterygium into the cornea. However, another similar disease, Ocular Surface Squamous Neoplasia (OSSN), is often clinically indistinguishable from pterygium and is also due to UV radiation. In contrast, squamous epithelial atypia is a precancerous lesion and therefore must be taken seriously. In a recent Australian study (published in Arch Ophthalmol, a top international clinical ophthalmology journal), 9.8% of patients operated on for pterygium were found to have OSSN. The researchers classified OSSN into 4 grades and found that nearly 40% were grade 2 or higher heterogeneous and highly susceptible to carcinogenesis, and even one case had transformed into squamous epithelial carcinoma. Therefore, if you find yourself with pterygium, you need to be cautious because of the possibility of cancer, so it is better to remove it early, and it is better to do pathological examination after surgery to make a clear diagnosis.