A 2021 meta-analysis by Liu et al. evaluated the prognostic role of Ki-67 in 929 patients across 10 melanoma studies and found that its overexpression, typically defined as ≥20% proliferation index considered a “high” cutoff (most studies had cutoffs ranging from 10 to 30%, with most studies deriving these thresholds post hoc), was associated with worsened OS (HR = 2.92; 95% CI, 2.17–3.91, p < 0.0001) [14]. Here, MKI67 is linked to melanoma.