PTCL-NOS is the largest group of  T-cell lymphomas, accounting for around half of the cases seen and 3-7% of all lymphomas.

Patients with PTCL-NOS have a median age of about 60 years, a striking male predominance, and usually present with widespread disease

While the International Prognostic Index has a significant association with treatment outcome, patients with IPI scores of 0/1 have only a 33% five-year failure-free survival and a 50% five-year overall survival. Patients with high IPI scores of 4/5 have a fiveyear progression-free survival of only 6% and a five-year overall survival of only 11%.

Primary treatment of PTCL-NOS should be within the context of a clinical trial if possible as standard therapy gives disappointing resultsOutside trial, CHOP remains the standard therapy. Consideration should be given to consolidation with auto-HSCT.