Lymphomatoid papulosis (LyP) is defined as a recurrent self-healing papulonodular eruption with the histological features of a (CD30+) cutaneous T-cell lymphoma.
Here we report that enhancer of zeste homolog 2 (EZH2), the catalytic subunit of polycomb repressive complex 2 that mediates histone H3 lysine 27 trimethylation, is overexpressed in CD30+ anaplastic cells in primary cutaneous anaplastic T-cell lymphoma and large-cell transformed cutaneous T-cell lymphoma.
We aimed to assess efficacy and safety of brentuximab vedotin versus conventional therapy for previously treated patients with CD30-positive cutaneous T-cell lymphomas.
We reviewed the clinical and pathologic features of 12 patients (male-female ratio, 7:5; median age, 61 years) with an atypical ELR histologically mimicking a primary cutaneous T-cell lymphoma such as Sézary syndrome or CD30+ T-cell lymphoproliferative disorder.
Primary cutaneous CD30-positive (anaplastic) large T-cell lymphomas and lymphomatoid papulosis are closely related types of cutaneous T-cell lymphoma with a favorable prognosis.
Three clonally related lymphoma lines (Mac-1, Mac-2A and Mac-2B) derived from progressive stages of CD30+ cutaneous T-cell lymphoma were found to constitutively secrete GM-CSF.
Twenty-one of 148 (14.2%) patients with CTCLs were positive for HHV7 DNA: nine of 39 (23.1%) SS, six of 14 (42.9%) CD30+ CTCLs and six of 24 (25.0%) LyP, and HHV7 DNA was negative in all 71 patients with MF.
The most frequent CTCL subtypes, in decreasing order of prevalence, were mycosis fungoides (MF), including its variants (75.7%); CD30+ primary cutaneous lymphoproliferative disorders (7.2%); and Sézary syndrome (SS) (3.1%).
Brentuximab vedotin is an antibody-drug conjugate, which combines a CD30 monoclonal antibody with the microtubule-disrupting agent monomethylauristatin E. The utility of brentuximab vedotin has been explored in a number of diseases, with a recent focus on T-cell lymphoma, particularly systemic anaplastic large-cell lymphoma (sALCL) and cutaneous T-cell lymphoma (CTCL), as well as other peripheral T-cell lymphoma (PTCL) histologies.
One mycosis fungoides and one pleomorphic CTCL harbored a KRAS(G13D) mutation; one Sézary syndrome and one CD30(+) CTCL harbored a NRAS(Q61K) amino acid change.
Based on the few cases reported herein, one might suggest that the prognosis mirrors that seen in other forms of cutaneous T cell lymphoma with mature small cell dominant infiltrates exhibiting an indolent pattern while a CD30 negative large cell T cell lymphoma would be expected to demonstrate an aggressive clinical course.