Targeted mutational profiling of peripheral T-cell lymphoma not otherwise specified highlights new mechanisms in a heterogeneous pathogenesis

Peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) is a diagnosis of exclusion making up the largest fraction (25–30%) of PTCL. Although traditionally considered a ‘wastebasket’ diagnosis, recent gene-expression results suggest the disease comprises two biologic sub-entities characterized by expression of the transcription factors GATA3 or TBX21 and their target genes. 1 The mutational landscape of PTCL-NOS remains largely undefined.