The natural history of conjunctival naevi in children and adolescents.

Objective: The objective of this study is to characterise the natural history of conjunctival naevi in a paediatric and adolescent population.

Methods: All children and adolescents referred to Moorfields Ocular Oncology Service for evaluation between January 2015 and 2020 were included. Exclusion criteria included age >20 years old and lack of anterior segment photographs. A total of 77 patients were included with a mean age of 12 years (standard deviation: 3.9; range, 4-20). The main outcome measures were: number of conjunctival naevi that grew, changed in pigmentation, required excisional biopsy, or were histologically malignant. If there was growth, the percentage increase in size was measured.

Results: At their first visit, 13% of patients (10/77) were discharged to local follow-up and 10% (8/77) proceeded to excisional biopsy, four further patients underwent excisional biopsy after a period of follow-up. On histopathological assessment, 92% (11/12) of lesions were benign conjunctival naevi. One patient, who had suspicious clinical features at presentation, had conjunctival melanoma. Fifty-nine patients were followed over a median of 1.1 years (interquartile range: 1.54; range, 3 months to 4 years). Eight per cent (5/59) of conjunctival naevi enlarged in diameter by a mean percentage increase in size of 2%, whereas 5% (3/59) showed increased pigmentation and 8.5% (5/59) showed decreased pigmentation.

Conclusions: Growth of conjunctival naevi in children is infrequent (8%) and the large majority of those excised are benign. Because of a lack of evidence, these patients are often followed for years in ophthalmic practice. This series demonstrates that prolonged follow-up may not be necessary.