A CASE OF HIGH-RISK CILIARY BODY MELANOMA ARISING IN AN EYE AFTER RESECTION OF AN IRIDOCILIARY MELANOCYTOMA.

PURPOSE: To report a case of a benign iridociliary melanocytoma recurring as malignant melanoma after excision.

METHODS

Observational case report with clinical data, slit-lamp examination findings, ultrasound biomicroscopy results, and histopathological and genetic analyses.

RESULTS

A 40-year-old African American woman initially presented with a superonasal iridociliary mass with a maximal thickness of 2.5 mm. Visual acuity of the involved eye was 20/25, intraocular pressure was 52 mmHg on maximal pressure-lowering medications, and Humphrey visual field testing revealed an inferior altitudinal defect. Fine-needle aspiration biopsy and incisional biopsy followed by tumor excision confirmed a benign melanocytoma. After 5 years of stability, possible recurrence was detected on ultrasound biomicroscopy as an increase in ciliary body thickness. The new lesion grew to a thickness of 5.1 mm over the next 18 months of observation. Fine-needle aspiration biopsy and gene expression profile of the recurrent lesion diagnosed a malignant melanoma with high metastatic potential (Class 2). The patient underwent plaque brachytherapy and has ongoing regression of the tumor.

CONCLUSION

Transformation of benign iridociliary melanocytoma to melanoma is rare. To the best of the authors' knowledge, this is the first documented case of a melanoma arising in an eye after initial excision of a melanocytoma. Close monitoring of these patients is warranted even years after the initial excision.