Correlation of fitzpatrick skin type and iris color with tumor size in 823 patients with uveal melanoma

To determine the correlation of Fitzpatrick Skin Type (FST) and iris color with tumor size (tumor thickness and basal diameter) in patients with uveal melanoma. Retrospective Cohort Retrospective cohort from a single ocular oncology center of 823 patients with uveal melanoma and documented FST, iris color, and tumor size. Patients were classified by FST (type I, II, and III–V) and iris color (blue, green, and brown) on the basis of external facial photography. There were no FST type VI patients. Tumor thickness was classified into small [< 3 millimeter (mm)], medium (3.1–8.0 mm), or large (> 8.0 mm), and basal diameter into small (< 10 mm), medium (10.1–15 mm) or large (> 15 mm). The correlation of FST and iris color with tumor thickness and basal diameter was evaluated using the Kruskal-Wallis H test. The FST classification was type I (n = 92, 11%), type II (n = 643, 78%), or III–V (n = 88, 11%), and iris color was blue (n = 472, 57%), green (n = 102, 12%), or brown (n = 249, 30%). A comparison of FST revealed differences in mean tumor thickness (P = 0.04) and basal diameter (P = 0.006). Iris color showed no difference for mean tumor thickness (P = 0.41) or basal diameter (P = 0.48). There was a statistically significant difference with brown iris color relative to FST III–V for mean tumor thickness (P = 0.003) and basal diameter (P = 0.001) but no difference with blue or green iris color (P > 0.05). Iris color alone showed no difference in tumor size, but those with brown iris color and FST type III–V demonstrated larger tumor thickness and basal diameter.