OCT, Histopathological Evaluation of Pterygium Warranted for OSSN Suspicion

close up of the advance pterygium during eye examination.
Patients should undergo routine tissue pathologic examination in the absence of clinical expertise or high-resolution imaging.

Ocular surface squamous neoplasia (OSSN) in clinically suspected pterygia occurs in approximately 0.3% of histopathologically analyzed samples, according to the results of a study published in Cornea. Because pterygia and OSSN share several clinical characteristics, researchers recommend preoperative anterior segment optical coherence tomography (AS-OCT) evaluation of OSSN suspects, or routine tissue pathologic examination where imaging technology is limited. 

“Identifying OSSN in pterygia samples is critical because their management and surgical approach differ, with a significant risk for OSSN recurrence and potential sequelae to misdiagnosis,” researchers explain.

The retrospective study assessed the prevalence of histopathologically confirmed OSSN in 348 clinically diagnosed pterygium samples during a 10-year study period.

The average age of participants was 58 years, with a nearly even split between men and women. In total, 16% of pterygia were recurrent at initial presentation, with histopathology exhibiting 1 case of OSSN. The patient had neither previous history of carcinoma nor history of herpes virus, human papillomavirus (HPV), or HIV. 

Researchers hypothesize that prolonged UV radiation from sunlight contributes to the pathophysiology of OSSN, with abnormal p45 tumor expression playing a role. In the current study, even though 8% patients with pterygium had a history of skin cancer, none developed OSSN during the study. 

The researchers assessed other potential risk factors including HPV, smoking, immunosuppression, and HIV. The relationship between HPV/HIV with OSSN could not be assessed due to the small sample size. The study authors note that in the US, only a limited number of patients with OSSN are immunocompromised. They stress that clinical experience could contribute to the clinical diagnosis of OSSN. 

Limitations of the current study include its retrospective design, use of nonspecific ICD-10 codes, and use of only excised pterygium samples.

Reference

Modabber M, Lent-Schochet D, Li JY, Kim E. Histopathological rate of ocular surface squamous neoplasia in clinically suspected pterygium specimens: 10-year results. Cornea. Published online on February 21, 2022. doi:10.1097/ico.0000000000002780