GROWTH OF PRESUMED CHOROIDAL NEVUS INTO MELANOMA OVER 4 YEARS IN BAP1 TUMOR PREDISPOSITION SYNDROME.

Abstract

To report a case of presumed choroidal nevus that eventually grew into melanoma in a patient with family history of choroidal melanoma and germline BAP1 mutation. Case report. A 55-year-old healthy white woman with a family history of uveal melanoma in her father, paternal aunt, and paternal cousin was referred for evaluation of an asymptomatic small pigmented choroidal lesion in her right eye, measuring 2 mm × 2 mm in basal diameter and 1 mm in thickness. There were no clinical risk factors. The patient was advised routine monitoring but returned 4 years later with intermittent photopsia. The choroidal mass demonstrated growth and suggestive of transformation into melanoma, measuring 9 mm × 6 mm in basal diameter and 2.5 mm in thickness with overlying orange lipofuscin pigment and no associated subretinal fluid. Fine-needle aspiration biopsy disclosed Chromosome 3 mosaic monosomy and Chromosomes 6 and 8 disomy. Iodine 125 plaque radiotherapy was provided. Based on growth to melanoma and strong family history of uveal melanoma, BAP1 germline mutation testing was performed, and the results were positive. This case demonstrates growth of a presumed choroidal nevus into melanoma in the setting of underlying germline BAP1 mutation. We suggest that small pigmented choroidal lesions be monitored closely in patients with germline BAP1 mutation or with family history of uveal melanoma, even in the absence of known local risk factors predictive of tumor growth.