Evaluation of follicular T-helper cells in primary cutaneous CD4+ small/medium pleomorphic T-cell lymphoma and dermatitis

J Cutan Pathol. 2013 Dec;40(12):1006-13. doi: 10.1111/cup.12234. Epub 2013 Oct 12.

Abstract

Background: CD4+ small/medium-sized pleomorphic T-cell lymphoma (SMPTCL) is a controversial primary cutaneous lymphoma, in which the candidate neoplastic cells express a follicular T-helper phenotype. We describe 16 cases of SMPTCL and compare expression of PD-1, CXCL-13 and ICOS in these tumors with 40 dermatitis cases.

Methods: Histopathologic examination and immunocytochemistry were performed for 16 tumors and 40 assorted dermatitis cases.

Results: All but one patient presented with solitary lesions. Each biopsy revealed a dense nodular non-epitheliotropic infiltrate of atypical T-cells. Neoplastic cells were CD3+/CD4+/CD8(-)/CD30(-). Cutaneous recurrence occurred in one patient over a median follow up of 8 months (range 5-36). All tumors widely expressed PD-1 and ICOS to a lesser extent. CXCL-13 stained much fewer cells. Of the dermatitis cases, PD-1 (most numerous) and ICOS labeled lymphoid cells in all cases, albeit fewer than in the tumors, and CXCL-13 was negative in 32. A rosette pattern of PD-1 expression was identified in all the SMPTCL cases but not in dermatitis.

Conclusions: There remains uncertainty about the appropriate nosological status of SMPTCL, which some authors consider to be a pseudolymphoma. However, this study suggests a significant difference in the prevalence and pattern of follicular T-helper cell markers between this tumor and lymphoid proliferations known to be reactive.

Keywords: PD-1; cutaneous lymphoma; follicular T-helper cell; pseudolymphoma; small/medium pleomorphic T-cell lymphoma.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Aged
  • Chemokine CXCL13 / biosynthesis
  • Dermatitis* / metabolism
  • Dermatitis* / pathology
  • Female
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Inducible T-Cell Co-Stimulator Protein / biosynthesis
  • Lymphoma, T-Cell, Cutaneous* / metabolism
  • Lymphoma, T-Cell, Cutaneous* / pathology
  • Male
  • Middle Aged
  • Neoplasm Proteins / biosynthesis*
  • Programmed Cell Death 1 Receptor / biosynthesis
  • Retrospective Studies
  • Skin Neoplasms* / metabolism
  • Skin Neoplasms* / pathology
  • T-Lymphocytes, Helper-Inducer* / metabolism
  • T-Lymphocytes, Helper-Inducer* / pathology

Substances

  • CXCL13 protein, human
  • Chemokine CXCL13
  • ICOS protein, human
  • Inducible T-Cell Co-Stimulator Protein
  • Neoplasm Proteins
  • PDCD1 protein, human
  • Programmed Cell Death 1 Receptor