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SHORT COMMUNICATION
Primary Cutaneous T-cell Lymphoma with Aberrant Expression of CD20
Verena G. FRINGS 1 , Sabine ROTH 2 , Anna-Liisa RIEDMILLER 1 , Kristina SCHÄFER 1 , Matthias GOEBELER 1 , Andreas ROSENWALD 2 ,
Eva GEISSINGER 2 and Marion WOBSER 1 *
Department of Dermatology, Venereology and Allergology, University Hospital Würzburg, Josef-Schneider-Straße 2, DE-97080 Würzburg, and
Institute of Pathology and Comprehensive Cancer Center Mainfranken, University Würzburg, Würzberg, Germany. *E-mail: [email protected]
1
2
Accepted Nov 10, 2016; Epub ahead of print Nov 14, 2016
Primary cutaneous T-cell lymphomas (CTCL) comprise
a heterogeneous group of extranodal non-Hodgkin’s
lymphomas. The most common subtype is mycosis
fungoides (MF), characterized by a superficial epidermo-
tropic infiltration of neoplastic CD3 + T cells (1). In the
early stages of MF, the disease commonly presents with
almost unrestricted life expectancy, whereas advanced-
stage MF usually runs a more aggressive course
(2). Immunohistochemical labelling of CD20 is
widely used for detection of cells of the B-cell
lineage (3, 4). Reactive B-cell infiltrates have
been sporadically described in CTCL (5). More-
over, aberrant expression of CD20 on neoplastic
T cells has been described in rare cases (6).
Based on 2 patients diagnosed with CD8 + CD20 +
CTCL this report provides additional insight
into potential diagnostic pitfalls and discusses
the putative prognostic and diagnostic value of
CD20 + cells in CTCL.
with multiple plaques and small tumors after 2 months (Fig. 1
g, h). Repeated histological examination of new or progressive
lesions invariably revealed the same epidermotropic infiltrate of
CD8 + , CD20 + , TCRβ + , TCRγ + neoplastic T cells with tracking of
the identical clone on sequential biopsies. Methotrexate (20 mg/
week) was initiated, but due to a significant further cutaneous
progress, was substituted by gemcitabine 600–900 mg/m 2 body
surface every 2 weeks producing disease stabilization.
CASE REPORTS
Patient 1. A 63-year-old man presented with macules
and plaques on the upper back and the groin (Fig. 1 a,
b). Biopsies revealed a dense lymphoid infiltrate with
extensive epidermotropism (Fig. 1c). Further immuno-
histochemical staining showed a T-cell rich infiltrate
with positivity for CD3 and CD5 and antigen loss of
CD2. There was prevailing expression of CD8 (Fig.
1d) over CD4 and both T-cell receptor (TCR) chains β
and γ were consistently positive (dual TCR expression).
CD56 was strongly positive within CD8 + T cells. CD30
was negative. Further immunohistochemical work-up
of the atypical lymphoid infiltrate revealed strong CD20
expression (Fig. 1e). B-cell markers, such as CD79a
and PAX-5, tagged only a few reactive dermal B cells.
Additionally conducted double immunolabelling con-
firmed