For DNA sequencing of these cTCL cases, hcCHP was designed to include regions in 68 genes commonly mutated in human lymphoma that included genes representing key signaling pathways (e.g., NFκB and TNFAIP3), WNT/B-Catenin (e.g., APC, CHD8, CELSR2), and NOTCH (NOTCH1, FBXW7), epigenetic processes (e.g., EP300, CREBBP, TET2, DNMT3A), tumor suppressor pathways (e.g., TP53, ATM, RB1, CUL9, PRKDC) and p53-related genes (e.g., TP53, TP63, CDKN2A, WWOX, and ANKRD11). This evidence concerns the gene RB1 and primary cutaneous T-cell non-Hodgkin lymphoma.