Lymphoma and plasma cell neoplasms
T / NK cell disorders
Primary cutaneous CD4+ small / medium T cell lymphoma

Topic Completed: 1 August 2011

Revised: 8 February 2019

Copyright: 2001-2018,, Inc.

PubMed search: Primary cutaneous CD4+ small / medium T cell lymphoma

Dragos C. Luca, M.D.
Page views in 2018: 955
Page views in 2019 to date: 621
Cite this page: Luca D. Primary cutaneous CD4+ small / medium T cell lymphoma. website. Accessed September 24th, 2019.
Definition / general
  • Cutaneous nodular proliferation of pleomorphic T-lymphocytes of undetermined significance
  • Rare, 2% of all cutaneous T cell lymphomas
  • Solitary plaque or nodule on face, neck, upper trunk
  • Lower extremity involvement is rare
Clinical features
  • Usually asymptomatic; only clinical feature is a solitary skin lesion
  • Rarely large tumors or multiple skin lesions
Case reports
Treatment and prognosis:
  • Favorable prognosis, 80% 5 year survival
  • Solitary skin lesions have an excellent prognosis (surgical excision or radiotherapy), multiple / large lesions may be more aggressive
Postulated normal counterpart
  • Skin homing CD4+ T cell
Gross description
  • Solitary plaque or nodule (more favorable) or multiple or large lesions (more aggressive)
Gross images

Images hosted on other servers:

Various images

Microscopic (histologic) description
  • Dense, diffuse or nodular dermal infiltrate with tendency to subcutaneous involvement
  • May have focal epidermotropism but if more than that, consider mycosis fungoides
  • Predominantly small / medium sized pleomorphic T cells sometimes with a small proportion (< 30%) of large pleomorphic cells
  • May have admixed reactive lymphocytes, histiocytes, eosinophils, plasma cells
Positive stains
Negative stains
  • CD8, CD30, cytotoxic markers, loss of a pan-T cell marker, EBV
Molecular / cytogenetics description
  • Clonal rearrangements of the TCR genes
  • No specific cytogenetic abnormality
Differential diagnosis
  • Reactive lymphoid infiltrate of the skin: also called pseudolymphoma or cutaneous lymphoid hyperplasia; no clonal TCR gene rearrangements, no loss of a pan-T cell marker
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