Histone deacetylation (HDAC) inhibitors including romidepsin (Istodax) and SAHA (vorinostat, Zolenza) have been shown to be particularly effective in the treatment of CTCL, suggesting a strong epigenetic component in its etiology [12,13,14,15,16]. Here, HDAC9 is linked to primary cutaneous T-cell non-Hodgkin lymphoma.