PTCL, NOS : Lymph Node
Peripheral T-cell Lymphoma (PTCL) is an extremely heterogenous family of neoplasms consisting of neoplastic lymphocytes with genotypic and phenotypic features of peripheral T cells. Peripheral T-cell Lymphoma, Not Otherwise Specified (PTCL, NOS) is the most common subtype in North America and Europe. The patients are usually adult or elderly and extranodal locations are commonly involved. The photomicrograph shows PTCL, NOS in a lymph node with diffuse effacement of nodal architecture. In some cases, the infiltrate is interfollicular or paracortical. The lymphoproliferative process often extends into perinodal tissues without preservation of the cortical sinus.