Clinical and Histopathological study of pterygia: a 15-year experience in Canada

Author Block: Dominique Geoffrion¹,   Emily Marcotte ¹, Dulce Lopez¹, Guillaume Mullie², Ana Beatriz Toledo Dias¹, Miguel N. Burnier¹.  ¹McGill University, ²Université de Montréal.

Author Disclosure Block: D. Geoffrion:   None.  E. Marcotte:  None.   D. Lopez:  None.  G. Mullie:   None.  A. Dias:  None.   M. Burnier:  None., Dominique Geoffrion: Not Current  Emily Marcotte: Not Current  Dulce Lopez: Not Current  Guillaume Mullie: Not Current  Ana Beatriz Toledo Dias: Not Current  Miguel N. Burnier: Not Current

Abstract Title: Clinical & Histopathological Study of Pterygia: A 15-Year Experience in Canada

Abstract Body: Purpose:  The presence of ocular surface squamous neoplasia in pterygium is a concern for ophthalmologists for several reasons, including the severe actinic damage from ultraviolet radiation (UV). The purpose of this study is to determine the correlation between epithelial atypia, melanocytic hyperplasia and the severity of actinic damage in biopsies of pterygium patients.      Study Design:  Retrospective, comparative study  Methods:   A comparative analysis of 376 pterygia collected from 2006 to 2021 at a single center was performed. All samples were retrieved from the MUHC-McGill University Ocular Pathology & Translational Research Laboratory at McGill University. Histopathologic examination was performed to report epithelial atypia, melanocytic hyperplasia and the severity of the actinic damage. Chi Square test was used for statistical purposes.   Results:  Mean age of patients was 57.3 ± 14.6 years, with 58% of males. Severe actinic damage was present in 3.7% of samples. Melanocytic hyperplasia was present in 4.4% of samples, while epithelial atypia in 9.1%.There was no significant correlation observed between epithelial atypia and melanocytic hyperpigmentation (P=0.381).  Conclusions:   This histopathological study suggests that epithelial atypia and melanocytic hyperplasia are independent from one another in pterygium patient excisional biopsies. Therefore, histopathological examination of all pterygium excisional biopsies should be performed in order to determine the presence of epithelial atypia (OSSN). Patient counselling can be done to highlight that melanocytic hyperplasia is not a risk factor for neoplasia in pterygium.