Primary Cutaneous CD4+ Small-/Medium-Sized Pleomorphic T-Cell Lymphoma: A Cutaneous Nodular Proliferation of Pleomorphic T Lymphocytes of Undetermined Significance? A Study of 136 Cases

Abstract

Patients with skin nodules characterized by the infiltrate of pleomorphic small/medium T lymphocytes are currently classified as "primary cutaneous CD4+ small-/medium-sized pleomorphic T-cell lymphoma" (SMPTCL) or as T-cell pseudolymphoma. The distinction is often arbitrary, and patients with similar clinicopathologic features have been included in both groups. We studied 136 patients (male:female = 1:1; median age: 53 years, age range: 3-90 years) with cutaneous lesions that could be classified as small-/medium-sized pleomorphic T-cell lymphoma according to current diagnostic criteria. All but 3 patients presented with solitary nodules located mostly on the head and neck area (75%). Histopathologic features were characterized by nonepidermotropic, nodular, or diffuse infiltrates of small- to medium-sized pleomorphic T lymphocytes. A monoclonal rearrangement of the T-cell receptor-gamma gene was found in 60% of tested cases. Follow-up data available for 45 patients revealed that 41 of them were alive without lymphoma after a median time of 63 months (range: 1-357 months), whereas 4 were alive with cutaneous disease (range: 2-16 months). The incongruity between the indolent clinical course and the worrying histopathologic and molecular features poses difficulties in classifying these cases unambiguously as benign or malignant, and it may be better to refer to them with a descriptive term such as "cutaneous nodular proliferation of pleomorphic T lymphocytes of undetermined significance," rather than forcing them into one or the other category. On the other hand, irrespective of the name given to these equivocal cutaneous lymphoid proliferations, published data support a nonaggressive therapeutic strategy, particularly for patients presenting with solitary lesions.

A Case of Primary Cutaneous CD4 Positive Small/medium T Cell Lymphoma

“…In our case, the age at the onset of the skin lesion was 63 years and she presented with multiple, multifocal lesions. Multifocal lesions similar to our case have been less commonly described [11][12][13][14] .…”

“…Immunohistochemically, CD3 and CD4 are positive, but CD8 and CD30 are negative in the majority of the case, and sometimes this is combined with the loss of the pan T cell markers 1,5,[11][12][13][14] . However, many studies have also reported tumors that are CD8 positive or CD4 negative 1,5,9,11,12 . In addition, many PCSM-TCL cases have shown a rich infiltrate of reactive B cells 14 .…”

“…Histologically, PCSM-TCL is characterized by a dense infiltration of small/medium sized pleomorphic T cells 9,[11][12][13][14] . Clonal T cell receptor gene rearrangement has been detected in most cases.…”

Peripheral T cell lymphoma in Asia

“…small/medium T-cell lymphoma Primary cutaneous CD4? small/medium T-cell lymphoma (CD4TCL) is associated with an excellent prognosis and presents characteristically with a solitary plaque or tumor that is generally localized on the face or the upper trunk and rarely presents with multiple papules, plaques, or tumors [80,81]. Histologically, CD4TCL shows nodularto-diffuse infiltrates with a predominance of CD3?, CD4?, CD8-, CD30-small-to-medium-sized pleomorphic T cells and a small proportion (\30 %) of large CD4 pleomorphic T cells.…”

Cutaneous lymphomas: A review

“…Often, distinguishing between primary cutaneous CD4+ small/medium-sized pleomorphic T-cell lymphoma and Tpseudolymphomas is difficult, even with TCR gene rearrangement analysis, which may be polyclonal in up to 40% of SMPTCL patients. For this reason, Beltraminelli et al suggested the name "cutaneous nodular proliferation of pleomorphic T lymphocytes of undetermined significance" for these cases 81 . In cases of a single lesion, treatment with surgical excision or radiotherapy may be performed.…”