Management of the cutaneous peripheral T-cell lymphomas: when subtypes matter.

The cutaneous T-cell lymphomas are a heterogeneous collection of many biologically and clinically distinct cancers. The World Health Organization 2008 reclassification of cutaneous lymphomas delineated provisional entities that were previously classified simply as primary cutaneous peripheral T-cell lymphoma not otherwise specified. Because of the relative rarity of cases, standard treatment recommendations and algorithms are lacking. However, identification of these subtypes is important as they can have vastly different clinical outcomes. Furthermore, cytokine treatments effective in classic mycosis fungoides or Sezary syndrome not only are ineffective, but also may exacerbate certain subtypes. The aim of this review was to summarize the biological bases of the recently defined entities, reinforce the importance of acute clinical/pathologic diagnosis, and propose treatment strategies based on the available data.