Patient charts in 2 cohorts with uveal melanoma were reviewed and compared for patients with light, intermediate, and dark irides. Clinical, histopathologic, and genetic data in addition to metastasis and survival information were documented and compared.
A retrospective chart review of patients who were enucleated for ciliary body and choroidal melanoma and had a recorded iris color in Leiden, The Netherlands, was performed. A second cohort of patients with posterior uveal melanoma treated by enucleation or conservative treatment who had recorded iris color from Wills Eye Hospital in Philadelphia also was included. Clinical, histopathologic (when available), and genetic data in addition to metastasis and survival information were documented and compared between patients with light, intermediate, and dark irides.
In the Leiden cohort, patients with lighter irides had thinner tumors and lighter pigmentation of their uveal melanoma. There was no significant difference in chromosome 3 or 8q, BAP1 staining, or overall survival between the 3 iris groups in either the Leiden or Philadelphia cohorts. However, copy number changes for mutations in chromosome 3 and 8q worsened survival outcomes significantly in patients with light and intermediate iris colors, but not in patients with dark irides.
A few previous studies have suggested that a lighter-colored iris was associated with a worse prognosis, but that was not corroborated with this study. However, when a chromosomal mutation associated with a worse prognosis was identified, there was a worse survival in patients with tumors with less pigmentation. Iris tumor color may be subjective, potentially affecting how translatable this data is to multiple physicians, but this paper documents similar results in large databases from different providers.
While this study does not currently impact clinical practice, it does suggest that chromosome status may yield different information for patients with posterior uveal melanoma depending on their iris color. Documenting iris color of patients with uveal melanoma may be of some prognostic significance in the future when we are able to better understand the relationship between pigmentation and chromosomal status.