Indeterminate melanocytic proliferations of the conjunctiva

Objective: To test the hypothesis that a subset of conjunctival melanocytic proliferations exists that cannot be reproducibly classified as benign, ma lignant, or indeterminate. Methods: Three groups of excisional biopsy specimens of conjunctival melano cytic proliferations were evaluated by a panel of 5 ophthalmic pathologists . These groups included lesions that we considered to represent benign (gro up 1 [n = 5]),malignant (group 2 [n = 5]),and indeterminate melanocytic pro liferations (group 3 [n = 5]). The panel classified the same sections in al l 3 groups in a randomized, masked fashion, first without and then with a c linical history of patient age, sex, and race. The kappa statistic was used to quantify the degree of agreement among observers. Results: There was strong concordance among the panel members for both grou p 1 (benign [kappa = 0.76]) and group 2 (malignant [ kappa = 0.70]) melanoc ytic proliferations. There was no concordance of the panel for group 3 (ind eterminate) lesions (kappa = -0.045). The concordance for groups 1 and 2 an d lack of concordance for group 3 lesions were independent of knowledge of clinical history of age, sex, and race. Conclusion: A subset of melanocytic proliferations of the conjunctiva exist s that cannot be reproducibly classified by pathologists as benign, maligna nt, or indeterminate.