Spleen
Hematogenous neoplasms
Peripheral T cell lymphoma (NOS)

Author: Jaleh Mansouri, M.D. (see Authors page)

Revised: 7 March 2018, last major update October 2013

Copyright: (c) 2003-2018, PathologyOutlines.com, Inc.

PubMed Search: Peripheral T cell lymphoma[TIAB] spleen

Cite this page: Mansouri, J. Peripheral T cell lymphoma (NOS). PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/spleenTcellymphoma.html. Accessed August 17th, 2018.
Definition / general
  • Heterogeneous group of nodal and extranodal mature T cell lymphomas with mostly CD4+ central memory T cell as postulated normal counterpart
  • Lymphomas in this group do not possess specific site / genetic characteristics of any of the defined subtypes of peripheral T cell lymphoma in the current WHO classification (Hum Pathol 2013;44:1927)
Terminology
Epidemiology
  • Occurs most frequently in adults (median age 55 - 60 years) with a 2:1 male to female ratio
Sites
  • Lymph nodes, with bone marrow, spleen, liver and other extranodal sites in advanced disease
Clinical features
  • Lymphadenopathy, often with B symptoms
  • May sometimes be associated with hemophagocytic syndrome
Diagnosis
  • Lymph node excisional biopsy
  • Bone marrow biopsy (for staging)
  • Flow cytometry (limited information)
  • TCR gene rearrangements
  • Cytogenetics studies
Prognostic factors
  • Often aggressive course
  • Bone marrow involvement
  • Positivity for Epstein-Barr virus (EBV)
  • Evidence for aberrant regulation of the NFkB signaling pathway
  • High Ki67 rate (> 70%) thought to confer worse prognosis
  • 5q, 10q, 12q deletions associated with better prognosis
Case reports
Treatment
  • Anthracycline based chemotherapeutic regimens, radiotherapy, allogeneic or autologous stem cell transplantation
Microscopic (histologic) description
  • Polymorphous tumor cells, often with clear cytoplasm
  • Tumor often confined to periarteriolar lymphoid sheath and marginal zone
  • Epithelioid histiocytic reaction
  • Caveat:
    • May see EBV+ Reed-Sternberg like cells in certain types of PTCL NOS, such as follicular variant (see below), need to differentiate from Hodgkin lymphoma (Am J Surg Pathol 2013;37:816)
  • Three PTCL NOS histologic variants described (WHO classification, 2008):
    1. Lymphoepithelioid (Lennert lymphoma):
      • Diffuse interfollicular growth pattern with mostly small cells admixed with epithelioid histiocytes, Reed-Sternberg-like cells and larger atypical blasts
      • Neoplastic cells are CD8+
    2. Follicular:
      • Intrafollicular or perifollicular aggregates of atypical clear cells and hyperplastic or transformed germinal follicles
      • May have associated t(5;9) translocation
    3. T zone:
      • Perifollicular growth pattern with mostly small cells having minimal cytologic atypia
      • Neoplastic cells are CD3+ and CD4+
Microscopic (histologic) images

Images hosted on other servers:

Diffuse pattern

Prominent postcapillary venules

Tumor cells with lobated nuclei

Atypical lymphoid infiltrates

CD3+, aberrant CD2+ and CD79+

Positive stains
Negative stains
Flow cytometry description
  • Nonspecific; often shows aberrant T cell immunophenotype with frequent loss of T cell markers (CD5)
  • Usually CD7, CD4 / CD8, CD52
Molecular / cytogenetics description
  • Clonal rearrangement of TCR genes usually present
  • Various complex karyotypes with gain of 7q, 8q, 17q, 22q and loss of 4q, 5q, 6q, 9p, 10q,12q, 13q
Differential diagnosis