CD5 and acute lymphoblastic leukemia: In addition, when sex, age, and CD5/CD6 ratio were included in univariate and multivariate COX regression models for survival analysis, the results indicated that CD5highCD6high was an independent prognostic predictor of OS in T-ALL patients (HR = 0.39, 95% CI: 0.23–0.65, P < 0.001).