Investigating Clinically Invisible Ocular Surface Squamous Neoplasia ( OSSN ) in Pterygium Excisions

Background To determine the prevalence of clinically unsuspected ocular surface squamous neoplasia (OSSN) in pterygia excised in a high ultraviolet (UV) exposure region of Australia. Methods Retrospective cross‐sectional prevalence study of all primary pterygium excisions by a single surgeon on the Sunshine Coast, Queensland, between October 2019 and March 2023. Of 174 procedures screened, 125 specimens were included: lesions at least 2.0 mm from the limbus, clinically diagnosed as benign. Eyes with pre‐operative suspicion of OSSN, recurrent pterygium, non‐conjunctival lesions and those without a retrievable histology report were excluded. All specimens were submitted for histopathology regardless of appearance; any epithelial dysplasia or carcinoma in situ was classed as OSSN‐related pathology. Age and sex were compared using t‐tests and chi‐square tests; prevalence is reported with Wilson score 95% confidence intervals (CI). Results Of 125 specimens (42 women, 83 men; mean age 63.6 ± 12.7 years), 24 (19.2%; 95% CI, 13.3–27.0) showed OSSN‐related changes: carcinoma in situ in 4 (3.2%; 95% CI, 1.3–7.9), moderate‐to‐severe dysplasia in 5 (4.0%; 95% CI, 1.7–9.0), and low‐grade dysplasia in 15 (12.0%; 95% CI, 7.4–18.9). Dysplasia was more common in men (21.7% vs. 14.3%) and in older patients, though neither difference reached significance ( p = 0.321 and 0.288). No included lesion was recorded as clinically suspicious pre‐operatively. Conclusions Histopathology identified dysplastic or in situ change in nearly one in five clinically benign pterygia from this high‐UV population. These findings support submitting excised pterygium tissue for histopathological examination, particularly where UV exposure is intense.