Photo Credit: Ilya Lukichev

The following is a summary of “Understanding choroidal nevus risk factors for transformation into melanoma,” published in the February 2024 issue of Dermatology by DeSimone, et al.

Choroidal nevi are common intraocular tumors in the United States, occurring in approximately 5% of Caucasian adults. These nevi pose several risks, including vision loss from subfoveal nevi, subretinal fluid accumulation, and potential transformation into malignant choroidal melanoma. For a study, researchers sought to identify clinical risk factors predictive of benign melanocytic choroidal nevus transformation into malignant melanoma. Analyzing 2,355 cases longitudinally using multimodal imaging, we identified specific clinical features associated with this transformation.

These features include tumor thickness exceeding 2 mm on ultrasonography, presence of subretinal fluid on optical coherence tomography, symptomatic vision loss of 20/50 or worse, presence of orange pigment on fundus autofluorescence, detection of a melanoma hollow on ultrasonography, and diameter greater than 5 mm on fundus photography. These factors are remembered with the mnemonic “TFSOM-DIM” (“To Find Small Ocular Melanoma Doing Imaging”).

Analysis of these factors revealed a Kaplan-Meier mean five-year risk ranging from 1% with no risk factors to 55% with all five factors present. Combinations of four or five risk factors show particularly high rates of transformation, underscoring the importance of recognizing clinical and imaging features indicative of malignant transformation in choroidal nevi.

Reference: sciencedirect.com/science/article/abs/pii/S0738081X23001773