Iris melanocytoma in child diagnosed by fine needle aspiration biopsy

Anterior Uveal Melanocytoma: Role of Diagnostic FNAB

Introduction

Anterior uveal melanocytoma (AUM) pose a diagnostic challenge as they can mimic growing melanomas. Establishing a definitive diagnosis of melanocytoma necessitates cytologic or histopathologic confirmation. We describe the clinical presentation and characteristics of fifteen pathologically proven AUM cases and assess the role of fine needle aspiration biopsy (FNAB) as a safe and effective tool for diagnosis.

Methods

Retrospective review of pathologically confirmed AUM cases was performed. Demographic data, presenting symptoms, clinical features, diagnostic approach, cytological and histological features, and clinical outcomes were collected.

Results

Fifteen patients with pathologically confirmed AUM were identified. The mean and median age of diagnosis were 50 and 53 years, respectively (range 3-77 years). The melanocytoma was localized to the iris (5, 33%) or ciliary body (7, 47%), and 3 patients had iridociliary involvement (20%). Presentation was due to concern for growth in 4 (29%), visual symptoms in 1 (7%), and was an incidental finding in 10 (64%) patients. Pigmentation of the tumor varied with 9 (60%) appearing brown and 3 (20%) black in color. The color of 3 (20%) ciliary body tumors could not be assessed. The diagnosis was confirmed with FNAB in 6 (40%), excisional biopsy in 7 (47%), and incisional biopsy in 2 (13%). Cytologic and histologic preparations demonstrated predominance of round to polygonal cells with heavily pigmented cytoplasm and small round nuclei. One patient who underwent excisional biopsy had prior FNAB that was interpreted as suspicious for melanoma (false-positive). Instances of false-negative cytology were not observed as demonstrated by the subsequent stable clinical course during the mean follow-up of 21.2 months (range = 1.0-63.0 months). FNAB-related complications were not observed in any case.

Conclusion

FNAB offers a minimally invasive and safe diagnostic approach for pathologic confirmation of AUM. However, limitations of FNAB including false-negative and false-positive biopsies must be considered when excluding underlying malignancy. Continued observation to document tumor stability should be considered.

A Pigmented Iris Lesion

A patient in their mid-60s presented with a left iris pigmented lesion that had been present for decades and remained stable in size. What would you do next?

A case of choroidal melanocytoma mimicking a choroidal melanoma

A 17-year-old young girl was seen by us with complaints of progressive, painless decreasing vision in one eye for the last 4 years. No other supporting history could be elucidated. On examination, a large choroidal mass was found. Since the features were suggestive of malignant melanoma of the choroid, an enucleation of the eye was performed. Subsequently, histopathological examination of the enucleated eye revealed findings consistent with melanocytoma of the choroid. This case is unique in that the patient was of relatively young age and the tumor was huge compared to previous such reports.