Prevalence, treatment, and outcomes of coexistent ocular surface squamous neoplasia and pterygium

Abstract

Purpose: The purpose of this study was to determine the prevalence of ocular surface squamous neoplasia (OSSN) coexisting with pterygia in South Florida and to study the treatment and related outcomes.

Design: Noninterventional retrospective study.

Participants: A total of 2005 patients with surgically excised pterygia at the Bascom Palmer Eye Institute from 2000 to 2010.

Methods: Pathology reports of patients with pterygia were reviewed for evidence of OSSN. Patients were divided into the following groups: pterygium and no OSSN (group 1), clinically suspected OSSN with pterygium (group 2), and unexpected OSSN with pterygium found on histopathology (group 3). Clinical charts of patients in groups 2 and 3 were reviewed.

Main outcome measures: Period prevalence, treatment, and outcome.

Results: In surgically excised pterygia, the prevalence of coexistent OSSN was 1.7% (n = 34), of which 41% (n = 14) were clinically suspected preoperatively (group 2) and 59% (n = 20) were unexpectedly found on histopathology (group 3). Clinically suspected OSSN with pterygia was generally treated with wide surgical margins and cryotherapy, whereas unexpected OSSN with pterygia was treated with simple excision, followed by adjuvant interferon treatment in 30% (n = 6). After a mean follow-up of 2 years, there were no recurrences in the suspected OSSN group and 2 recurrences in the unexpected OSSN group. The recurrence rate in the latter group was 11% at 1 year and 24% at 2 years.

Conclusions: Ocular surface squamous neoplasia is uncommonly found to coexist with pterygium. The prognosis in suspected OSSN cases is excellent, with no recurrences noted despite positive margins in 50% of cases. The recurrence rates of unexpected OSSN mirrors that of OSSN not associated with pterygium, and thus vigilance for recurrence is important.

Figure 1

Representative slit lamp biomicroscopy photographs demonstrating the study groups. A: pterygium (group 1); B: pterygium with clinically suspected ocular surface squamous neoplasia (OSSN), C: pterygium with OSSN that was clinically unexpected.

Figure 2

Representative histopathology images demonstrating ocular surface squamous neoplasia grades. A) Conjunctival intraepithelial neoplasia (CIN): dysplasia, mild. The conjunctival epithelium displays faulty epithelial maturational sequencing that extends to approximately 25% of the epithelial thickness. B) CIN: dysplasia, moderate. The conjunctival epithelium displays faulty epithelial maturational sequencing that extends to approximately 50% of the epithelial thickness. C) CIN: dysplasia, severe. The conjunctival epithelium displays faulty epithelial maturation sequencing that extends to near full thickness. D) CIN: Carcinoma in situ. The conjunctival epithelium displays faulty epithelial maturational sequencing that extends to full thickness. E) Conjunctival squamous cell carcinoma. The conjunctival epithelium displays faulty epithelial maturational sequencing that extends to full thickness. Foci of invasion of atypical epithelial cells into the underlying substantial propria are identified. All images stained with hematoxylin and eosin.

Figure 3

Histopathology images demonstrating coexistent pterygium and ocular surface squamous neoplasia (OSSN). A,B) Histopathology of a patient belonging to group 2 with marked solar elastosis (arrowhead) and overlying epithelium with faulty maturational sequencing (+), indicating OSSN with an underlying pterygium. In this case, OSSN was anticipated by the surgeon. C, D) Histopathology of a patient belonging to group 3 demonstrating focus of OSSN (+) with a clear transition (arrow) towards unremarkable epithelium (−). Solar elastosis (arrowhead) is present, indicating a pterygium. OSSN was found incidentally in pathology and was not suspected by the surgeon. Hematoxylin & Eosin (H&E).

Figure 4

Kaplan Meier survival curve demonstrating the recurrence rate of ocular surface squamous neoplasia (OSSN) over time in patients with suspected and unexpected OSSN with pterygium.