To report the impression cytology (IC) results of clinically diagnosed ocular surface melanocytic lesions.

Ten patients with the clinical diagnosis of an ocular surface melanocytic lesion underwent IC using cellulose acetate strips and Periodic acid Schiff-Papanicolaou staining. Excisional biopsy of the lesions was performed pending either observation of atypical cells in IC or at patient’s request, and the excised specimens were subjected to histopathological analyses. The agreement between the clinical diagnoses and IC results and between the IC results and histopathology were statistically calculated.

Clinical diagnoses were nevi in 6, primary acquired melanosis (PAM) with atypia / melanoma in 2, and atypical nevus versus pigmented conjunctival intraepithelial neoplasia (CIN) in 2. The IC results were suggestive of a benign nevus in 7, PAM with atypia /melanoma in 2 and CIN versus an atypical epithelioid-type melanocytic lesion in 1. IC results were consistent with clinical diagnoses in 9 cases (Cohen’s kappa index of 0.83) and excluded CIN in 1. Histopathology in 6 cases disclosed benign melanonevus in 3, malignant melanoma in the context of PAM with atypia in 2 and CIN in 1 case. The histologic results were well correlated with the IC features (Cohen’s kappa index of 0.74).

The IC results in our series by demonstrating typical cytomorphological features of the ocular superficial layers diagnosed the real identity of melanocytic-looking ocular surface lesions in majority of the cases. Although IC does not substitute histopathology, given the high correlation of IC results with histopathology, it can be of great assistance in the diagnosis and management of patients with clinically diagnosed ocular surface melanocytic lesions.