Shown are TRECs with respect to clinical stage (P = .034) and cluster (P = .011). As shown previously,⁴⁷  TRECs decreased significantly across all clinical stages, and contracture increased from early-stage to late-stage CTCL, indicating loss of T-cell receptor diversity. Clusters 1 and 3 had the lowest TREC levels and highest contractures, while cluster 2 had the highest TREC levels and the lowest contractures. These findings significantly correlate with the clinical observation of poorer outcome in clusters 1 and 3. P values calculated based on ANOVA.