Apoptosis in CD30-positive lymphoproliferative disorders of the skin

The spectrum of CD30-positive cutaneous lymphoproliferative disorders (CD30+ CLPD) includes lymphomatoid papulosis (LyP), primary cutaneous CD30+ large T-cell lymphoma (LTCL) and rare borderline patients. Despite their malignant histopathology, CD30+ CLPD exhibit a low-grade malignant course with an excellent prognosis and a characteristic tendency for spontaneous regression. Apoptosis of tumour cells is considered a principal mechanism of tumour regression. We examined the proliferation and apoptosis rates as well as the expression of apoptosis-related proteins in various clinical entities, tumour cell lines and evolutional (evolving and regressing) stages of CD30+ CLPD. Skin biopsies of LyP (n = 20) and LTCL (n = 19) and five CD30+ lymphoma cell lines were analysed by means of immunohistochemistry and Western blotting in order to evaluate the proliferation (Ki67), apoptosis (FragEl) and expression of Bax, Bcl-x, C-kit and Mcl-1. A significantly higher apoptotic index (AI) was found in LyP (AI = 12.5%) than in LTCL (AI = 3.1%, P < 0.005). Bax was expressed by the majority of tumour cells in all forms of CD30+ CLPD and CD30+ cell lines. However, no Bax expression was found in tumour cell lines derived from systemic CD30+ lymphomas, which lack spontaneous regression and display an aggressive clinical course. No significant correlation was found between the expression of apoptosis-related proteins and the tumour type and evolutional stage of CD30+ CLPD. We conclude that the higher AI in LyP may contribute to the regression of LyP lesions and the excellent prognosis of the disease. Pro-apoptotic protein Bax is expressed at high levels in CD30+ CLPD and may play a crucial role in mediating apoptosis of tumour cells.     

IL-4 production by CD8+ lymphomatoid papulosis, type C, attracts background eosinophils

There are two subsets of CD8+ T cells: Tc1 and Tc2. INF-gamma production by Tc1 cells causes granulomatous inflammation. IL-4 production by Tc2 cells attracts eosinophils. A 76-year-Caucasian female presented with CD8+ lymphomatoid papulosis (LyP), type C. We hypothesized that the LyP cells belonged to the Tc2 subset because of abundant background eosinophils. Hematoxylin and eosin and immunohistochemical stains were carried out on tissue sections from a skin punch biopsy. Antibodies for immunohistochemical stains included CD3, CD4, CD5, CD7, CD8, CD30, CD56, ALK-1, clusterin and IL-4. There was involvement of the dermis by a dense lymphoid infiltrate composed of large atypical cells and numerous eosinophils. The LyP cells expressed CD5, CD8, CD30 and IL-4. Keratinocytes showed a membranous pattern of immunoreactivity for IL-4. IL-4 production by CD8+ LyP, type C indicates that it belongs to the Tc2 subset. The cytokine milieu produced by the LyP cells attracted eosinophils. The IL-13R complex on keratinocytes bound IL-4 and produced a membranous staining pattern. Although CD8+ LyP is rare, we believe that this CD30+ lymphoproliferative disorder should be included in the World Health Organization-European Organization for Research and Treatment of Cancer classification of cutaneous T-cell lymphomas.     

Lymphomatoid papulosis with pseudocarcinomatous hyperplasia in a 7‐year‐old girl: a case report

Lymphomatoid papulosis (LyP) belongs to the group of cutaneous CD30+ lymphoproliferative disorders. Pseudocarcinomatous hyperplasia has rarely been reported in patients with LyP. In this report, we describe a case of LyP presenting as pseudocarcinomatous hyperplasia. The patient was a 7‐year‐old girl who presented with a recurrent papulonodular eruption on her face and trunk for 2 months. Histopathologic examination revealed an irregular growth of hyperkeratotic epidermis into the whole dermal layer with marked nests of squamous cells in the background of diffuse atypical lymphoid cells, eosinophils and neutrophils. The large atypical cells were positive for CD30 and CD3, but negative for CD4, CD5, CD8, CD20 and CD56. A TCR‐γ clone was identified by polymerase chain reaction (PCR). The correct diagnosis in cases of LyP with overlying pseudocarcinomatous epithelial hyperplasia can be very difficult both clinically and histopathologically. Clinical and histopathologic characteristics should be integrated to avoid an erroneous diagnosis of squamous cell carcinoma or keratoacanthoma.     

Lymphomatoid papulosis with a natural killer-cell phenotype

Lymphomatoid papulosis (LyP) is defined as a recurrent self-healing papulonodular eruption with the histological features of a (CD30+) cutaneous T-cell lymphoma. The atypical cells usually have a CD3+/-, CD4+/-, CD8-, CD30+, CD56- T-cell phenotype. We report an unusual case of LyP, in which the atypical cells expressed a CD3-, CD4-, CD8-, CD30+, CD56+ phenotype. Detailed phenotypic and genotypic analysis confirmed that these cells had a natural killer (NK)-cell phenotype. Lymphomas with an NK-cell phenotype usually have a poor prognosis. However, the waxing and waning of papular lesions for more than 20 years and the excellent response to low-dose oral methotrexate in this patient suggest similar clinical behaviour to LyP cases with a T-cell phenotype.     

趋化性细胞因子受体CCR4和CXCR3在特应性皮炎患者外周血的表达

目的为研究特应性皮炎患者外周血趋化性细胞因子受体CCR4和CXCR3在特应性皮炎的发病过程中的作用。方法采用三色流式细胞仪测定20例特应性皮炎患者和30例健康对照者外周血趋化性细胞因子受体CCR4和CXCR3的表达水平。结果特应性皮炎患者外周血CCR4+CD4+T细胞的水平明显高于对照组(P<0.01);特应性皮炎患者外周血CCR4/CXCR3比率明显高于对照组P<0.01);特应性皮炎患者外周血CXCR3+CD4+T细胞的水平与对照组差异无统计学意义。结论趋化性细胞因子受体CCR4可能促进了Th2细胞从血液进入特应性皮炎患者炎症皮损。     

Nickel-responding T cells are CD4+ CLA+ CD45RO+ and express chemokine receptors CXCR3, CCR4 and CCR10

BACKGROUND: Whereas T lymphocytes are widely accepted as effector cells determining the pathogenesis of allergic contact dermatitis, contradictory results have been found regarding the roles of different T-cell subsets. The use of various experimental models, involving long-term cultured T-cell lines or clones, may explain these contradictory results. OBJECTIVE: To investigate the involvement of distinct T-cell subsets in patients with nickel contact allergy. METHODS: Different T-cell subsets were directly isolated from peripheral blood mononuclear cells (PBMCs) of nickel-allergic patients, and their proliferative capacity, type-1 or type-2 cytokine secretion [measured by interferon (IFN)-gamma or interleukin (IL)-5 release] and phenotypical marker expression were analysed after stimulation with nickel. RESULTS: Only CD4+ CLA+ CD45RO+ and not CD8+ T cells proliferate and produce both type-1 (IFN-gamma) and type-2 (IL-5) cytokines in response to nickel. Moreover, cells expressing the marker CLA in combination with CD4, CD45RO or CD69 are increased after nickel-specific stimulation. Interestingly, in addition, CD45RA+ CLA+ cells showed an increased frequency after allergen-specific stimulation. Analysis of nickel-reactive T cells for expression of distinct chemokine receptors showed that both proliferative capacity and cytokine production are restricted to subsets expressing CXCR3, CCR4 but not CCR6. Fluorescence-activated cell sorting analysis of chemokine receptors expressed on nickel-stimulated T cells confirmed these results; a subset of T cells expressing CLA and CXCR3, CCR4 and, most importantly, CCR10 increased in response to allergen, while these CLA+ nickel-reactive T cells were all negative for CCR6. CONCLUSIONS: These findings demonstrate that freshly isolated nickel-reactive T cells can be characterized as CD4+ CLA+ memory T cells which express the chemokine receptors CXCR3, CCR4 and CCR10, but not CCR6.     

New variant lymphomatoid papulosis type E preceding and coexisting with mycosis fungoides – a case report and review of the literature

Angioinvasive (type E) lymphomatoid papulosis (LyP) is a recently described subtype of LyP presenting with eschar‐like lesions that can be mistaken for aggressive forms of angiocentric cutaneous T‐cell lymphoma. None of the cases of angioinvasive LyP described thus far have been associated with mycosis fungoides (MF). Herein, we describe a case of angioinvasive LyP type E coexisting with MF. The patient presented with an eschar on his chest and over time developed new nodules and large plaques with eschar formation, all of which resolved spontaneously over a period of a few weeks without intentional therapy. Biopsy revealed a CD30+ atypical inflammatory cell infiltrate with marked angiocentricity. Later, he developed erythematous annular scaly patches histologically consistent with MF. Our patient's clinical course confirms the indolent behavior characteristic of LyP despite the aggressive clinical and histologic appearance of lesions. The co‐occurrence of angioinvasive LyP and MF in our patient highlights the propensity for LyP type E to coexist with MF, as is characteristic of other LyP subtypes, and supports the theory that LyP and MF are related T‐cell lymphoproliferative disorders. Patients with LyP can present with large lesions exhibiting eschar formation and an atypical angiocentric/angiodestructive lymphoid infiltrate and should be spared overtreatment.     

MUM1 expression in cutaneous CD30+ lymphoproliferative disorders: a valuable tool for the distinction between lymphomatoid papulosis and primary cutaneous anaplastic large-cell lymphoma

Background Primary cutaneous CD30+ lymphoproliferative disorders include lymphomatoid papulosis (LyP) and primary cutaneous CD30+ anaplastic large T‐cell lymphoma (ALCL). Because of overlapping histological features, it is impossible to distinguish ALCL from LyP on histological grounds. MUM1 (Multiple Myeloma oncogene 1) is expressed in systemic ALCL and classical Hodgkin lymphoma. MUM1 expression has not been studied in detail in CD30+ lymphoproliferative disorders. Objectives To examine the expression of MUM1 in CD30+ lymphoproliferative disorders and to assess its value as a diagnostic marker. Methods Thirty‐one formalin‐fixed paraffin‐embedded specimens of LyP (n = 15), primary cutaneous ALCL (n = 10), secondary cutaneous infiltrates of systemic ALCL (n = 4) and secondary cutaneous Hodgkin lymphoma (n = 2) were analysed by immunohistochemistry with a monoclonal antibody against MUM1. Results Positive staining for MUM1 was observed in 13 cases of LyP (87%), two cases of primary cutaneous ALCL (20%), four cases of secondary cutaneous ALCL (100%) and two cases of secondary cutaneous Hodgkin lymphoma (100%). In 11 of 13 LyP cases (85%), MUM1 was displayed by the majority, i.e. 50–90%, of the tumour cells. In contrast to LyP and secondary cutaneous ALCL, only two cases of primary cutaneous ALCL (20%) harboured MUM1‐positive tumour cells. There was a statistically significant difference in the expression of MUM1 between LyP and primary cutaneous ALCL (P = 0·002) and between primary cutaneous ALCL and secondary cutaneous ALCL (P = 0·015). Conclusions MUM1 expression is a valuable tool for the distinction of LyP and ALCL and thus represents a novel adjunctive diagnostic marker in CD30+ lymphoproliferative disorders.     

Expression of cutaneous lymphocyte-associated antigen and TIA-1 by lymphocytes in pityriasis lichenoides et varioliformis acuta and lymphomatoid papulosis: immunohistochemical study

BACKGROUND: Pityriasis lichenoides et varioliformis acuta (PLEVA) and lymphomatoid papulosis (LyP) are benign self-healing cutaneous eruptions that may be clinically and histologically similar. The purposes of this study were to evaluate immunohistological characteristics of PLEVA and LyP and to investigate whether Epstein-Barr virus (EBV) may be present in PLEVA and LyP. METHODS: We performed an immunohistochemical staining in 12 cases of PLEVA and 8 cases of LyP using nine antibodies for CD3, CD4, CD8, CD30, CD45RO, CD56, CD79, cutaneous lymphocyte-associated antigen (CLA), and TIA-1. In situ hybridization was performed using fluorescein-conjugated oligonucleotide probes for EBV early regions (EBER). RESULTS: In PLEVA, immunohistochemical studies revealed that infiltrated lymphocytes consisted of mainly CD3-positive (5+), CD8-positive (4+ to 5+), CLA-positive (4+ to 5+) T cells and partly CD79 positive (+ to 2+) B cells. CD4-positive T cells were less than 25%. In LyP, immunohistochemical studies revealed that infiltrated lymphocytes consisted of partly CD3-positive (5+), CD8-positive (2+ to 3+), CLA-positive (3+ to 4+) T cells and partly CD79-positive (2+ to 3+) B cells. CD4-positive T cells were less than 10%. CD8 and CLA were more strongly expressed in PLEVA than in LyP. CD30 was strongly expressed in LyP but not expressed in PLEVA. CD79 was more expressed in LyP than in PLEVA. TIA-1 was not expressed in any cases. In situ hybridization using antisense EBER probe showed negative reaction in all cases. CONCLUSIONS: Immunohistochemical stains for CD8, CD30, CD79 and CLA may be valuable tools in the differential diagnosis between PLEVA and LyP. TIA-1 was negative in LyP, which means cytotoxic cells may not be implicated in the pathogenesis of LyP. It was a contradictory result to the previous results. The absence of EBV in PLEVA and LyP suggests that this virus may not be operative in the pathogenesis of these diseases. These results suggest that LyP and PLEVA are separate disorders, thus accounting for their variable prognosis.     

I Forgot to Shave My Hands: Spiny Keratoderma of the Palms and Soles

Lymphomatoid papulosis (LyP) is a cutaneous CD30+ lymphoproliferative disorder characterized by recurrent papulonecrotic or papulonodular lesions with histologic features of a malignant lymphoma and an excellent prognosis. Three morphologic types (A, B, and C) of LyP exist and typically display an immunophenotype of CD4+, CD8−, and CD30+. We present a case of a 63‐year‐old woman with a one‐year history of relapsing papulonecrotic skin eruptions. Biopsy of a lesion on the forearm showed a superficial and deep dermal wedge‐shaped infiltrate with large lymphoid cells (Type A LyP). A lesion on the abdomen showed a band‐like superficial dermal infiltrate composed of small lymphoid cells with extensive epidermotropism and cerebriform nuclei (Type B LyP). Lastly, a lesion on the buttock histologically showed a dense, diffuse dermal infiltrate composed of a mixture of small and large lymphoid cells (Type C LyP). In all three lesions, the atypical lymphocytes were immunoreactive to CD8 and CD30 and nonreactive to CD4. CD8 positive cases of LyP are rare in the literature and tend to occur in pediatric patients. Moreover, while approximately 10% of patients may present with lesions of both the type A and type B types, cases showing all three types of LyP are exceedingly rare.     

Lymphomatoid papulosis: a study of 18 cases*

Lymphomatoid papulosis (LyP) is a cutaneous eruption that is clinically benign but histologically malignant. To date, more than 300 cases have been published. About 10–20% of the patients develop a lymphoma. The purpose of this study was to make a clinicopathological study of 18 patients diagnosed with LyP in our hospital from 1973 to 1990, to characterize cellular infiltrates in the lesions, to find clonal populations of T-cells and to look for predictive factors of malignant lymphoma in LyP patients. Mean age was 48.7 years. The most frequent clinical lesions were papules (88.8%) followed by plaques (38.8%). The localizations were on extremities (100%), trunk (88%), face (22%), palms or soles (11%), perigenital (11%) and scalp (5%). Two patients have been free of disease for more than 5 years. IgA levels are increased in LyP patients. Neither HTLV I nor III can be considered as a cause of the LyP in any of our patients. Associated diseases were found in 6 cases (1 mycosis fungoides, 1 Hodgkin's disease, 2 anaplastic large-cell lymphoma and 2 large plaque parapsoriasis). Some types of parapsoriasis should be included in the ‘spectrum of Ki-1 lymphomas’. 52 skin biopsies were studied. 17% were type A of Willemze, 67% were type B and 15% were transitional. In 12 of the samples follicular or perifollicular infiltration was found. Follicular LyP should not be considered as a distinct type of LyP. Vasculitis is an uncommon finding in LyP. In all the cases studied, large atypical cells were CD30 +; 5/7 cases had lost CD5 and 4/5 cases had lost CD7. In one case, all T-cell antigens were negative. Cerebriform mononuclear cells were always recognized by T-cell antibodies and they were CD30 positive in only two cases. In one case there were more CD8 + than CD4 + cells. In 5 patients skin and blood samples for genetic rearrangement (beta-T) were taken. Only germinal line was found. We did not find any significant difference between those cases in which malignant lymphoma developed and those in which it did not.     

CC chemokine receptor 4 expression on peripheral blood CD4+ T cells reflects disease activity of atopic dermatitis

Recent studies indicate that Th1 and Th2 cells differ in their chemokine receptor expression and their responsiveness to various chemokines. Therefore, selective Th2 cell recruitment in Th2-predominant inflammatory diseases such as atopic dermatitis may be under the influence of some chemokines. It is reported that CC chemokine receptor (CCR) 4 is selectively expressed on Th2 cells whereas CXC chemokine receptor (CXCR) 3 is selectively expressed on Th1 cells. In this study we examined CCR4 and CXCR3 expression on peripheral blood CD4+ and CD8+ T cells obtained from adult atopic dermatitis subjects, and compared the results with those from patients with psoriasis vulgaris and healthy controls. CCR4 was preferentially expressed on CD4+ T cells from atopic dermatitis subjects and CXCR3 was preferentially expressed on CD4+ T cells from psoriasis vulgaris subjects. This CCR4 expression was prominent especially in severe atopic dermatitis subjects. CCR4 expression on CD4+ T cells in severe atopic dermatitis subjects decreased on improvement of disease activity. CD25 was preferentially expressed on CCR4+CD4+ T cells but not on CXCR3+CD4+ T cells in atopic dermatitis subjects. Cutaneous lymphocyte-associated antigen was also preferentially expressed on CCR4+CD4+ T cells but not on CXCR3+CD4+ T cells in atopic dermatitis subjects. CD4+ T cells in atopic dermatitis skin lesions were predominantly CCR4+ cells. Taken together, this study strongly indicates that CCR4+CD4+ T cells reflect disease activity and suggests that CCR4 expression is important for T cell infiltration into atopic dermatitis lesions. Thus, CCR4 may be a possible target for therapy of atopic dermatitis in the future.     

CD30+ lymphoproliferative disorder: primary cutaneous anaplastic large cell lymphoma followed by lymphomatoid papulosis

CD30+ large anaplastic lymphoid cells are seen in anaplastic large cell lymphoma (ALCL), and also in lymphomatoid papulosis (LyP) and other lymphoproliferative disorders. It can be difficult precisely to categorize these disorders with CD30+ cells. We report a case of primary cutaneous CD30+ ALCL with systemic metastases in whom the clinical disease subsequently evolved into LyP. The patient was initially administered cisplatin and etoposide and made a good response. Eighteen months later, recurrent, self-healing cutaneous small nodules appeared around the original tumour site without any systemic involvement. Histopathological examination of the recurrent lesions revealed infiltration with a mixture of cells that included neutrophils, eosinophils and CD30+ large anaplastic cells cytologically identical with those in the primary lesion. The anaplastic cells in both the primary and recurrent lesions were positive for monoclonal antibodies CD30, CD25 and a monoclonal antibody directed against the chimeric protein p80(NPM-ALK). These observations suggest the possibility that the ALCL and the subsequent LyP represent different clinical manifestations of proliferation of the same clone.     

Expression of T-cell activation marker CD134 (OX40) in lymphomatoid papulosis

BACKGROUND: CD134/OX40 and CD30 are transmembrane proteins from the tumour necrosis factor receptor (TNFR) family present selectively on activated T cells. TNFR-related proteins are crucially involved in the regulation of proliferation and survival of normal and malignant lymphohaematopoietic cells. CD30 has been used for the immunophenotyping and subclassification of cutaneous lymphomas; virtually nothing is known, however, about the expression pattern of CD134 in lymphoid skin malignancies. OBJECTIVES: To determine CD134 expression in cutaneous lymphoma and benign inflammatory disorders.METHODS: Biopsy material was obtained from patients with lymphomatoid papulosis (LyP, n = 42), mycosis fungoides (n = 21), Jessner's infiltrates (n = 10) and non-specific dermatitis (n = 14). The expression of CD134 and CD30 was scored after immunohistochemical staining with appropriate monoclonal antibodies. The proportion of G2 + S phase cells was determined by laser scanning cytometry from nuclei obtained from paraffin-embedded biopsies. RESULTS: Few, single and scattered CD134+ cells (< 10%) were observed in the benign inflammatory infiltrations and in mycosis fungoides. A subset of 16 patients with LyP presented with clusters of CD30+ CD134+ cells. There was no correlation between the magnitude of CD134 expression and the histological type or the proportion of G2 + S cells in LyP. CD134 immunoreactivity was lower than expected in patients with LyP and another lymphoid malignancy (P < 0.001, Fisher's exact test). CONCLUSIONS: CD134 is strongly expressed in a proportion (38%) of patients with LyP, but not in mycosis fungoides or benign lymphocytic infiltrations. Loss of CD134 expression in LyP may be a marker of an increased risk of second lymphoid malignancy.     

High level of thymus and activation-regulated chemokine in blister fluid and sera of patients with bullous pemphigoid

BACKGROUND: Bullous pemphigoid (BP) is an autoimmune blistering disease characterized by eosinophilia and high serum IgE levels. The accumulated evidence suggests that various cytokines are involved in the lesional skin of patients with BP. Recently, thymus and activation-regulated chemokine (TARC/CCL17), a CC chemokine, was identified as a selective chemoattractant for CC chemokine receptor 4 (CCR4)-expressing cells. OBJECTIVE: In this study, we examined the involvement of TARC in patients with BP. METHODS: We determined the fluid and serum TARC levels in patients with BP by enzyme-linked immunosorbent assay and compared the serum TARC levels with the eosinophil numbers in peripheral blood. We also compared the serum TARC levels in five patients with BP before and after they were treated. Moreover, we examined TARC, CCR4 and CXC chemokine receptor 3 (CXCR3) expression in the lesional skin of patients with BP by immunohistochemical procedures. Furthermore, we measured CCR4 positivity in CD4+ CD45RO+ cells of peripheral blood mononuclear cells (PBMCs) in patients with BP and healthy control subjects. RESULTS: The fluid TARC levels in patients with BP were significantly higher than those in blisters from burn patients or suction blisters of healthy control subjects. The serum TARC levels in patients with BP were also significantly higher than those in pemphigus vulgaris (PV) patients and healthy control subjects, and decreased after the treatment. The serum TARC levels in patients with BP significantly correlated with the eosinophil numbers in peripheral blood (r = 0.72, P < 0.002). Immunohistochemistry showed a strong reactivity of TARC in the epidermal keratinocytes (KCs) of BP. Moreover, both CCR4 and CXCR3 were expressed on the dermal infiltrating CD4+ T cells mainly beneath the bullae of patients with BP. Fluorescence-activated cell sorting analysis showed a higher percentage of CCR4 positivity in CD4+ CD45RO+ cells of PBMCs in patients with BP than that in healthy control subjects, while there was no significant difference of CXCR3 positivity in CD4+ CD45RO+ cells of PBMCs between patients with BP and healthy control subjects. CONCLUSIONS: These findings strongly suggest that TARC may be one of the important chemokines that are involved in the pathogenesis of BP.     

Lymphoma- and leukemia-associated cutaneous atypical CD30+ T-cell reactions

Cutaneous CD30+ lymphoid infiltrates appear cytologically atypical and occasionally may be misinterpreted as recurrent disease when they occur in patients treated for other primary hematologic malignancies. We recently encountered two such cases and present our findings. One patient with B-cell lymphoma and another with myeloid leukemia developed cutaneous eruptions after chemotherapy displaying highly atypical perivascular lymphoid cells on histology that mimicked recurrent disease. In both cases, the lymphocytes were CD30+ T cells by immunohistochemistry. The skin lesions spontaneously resolved and have not recurred. Because one case was initially misinterpreted as recurrent leukemia, we conclude that close clinical correlation and immunophenotypic confirmation should be done for atypical cutaneous lymphoid infiltrates in patients with primary hematologic malignancies. We discuss the differential diagnosis of atypical CD30+ infiltrates in this setting, which include recurrent lymphoma or myeloid leukemia, primary cutaneous anaplastic large cell lymphoma (ALCL), lymphomatoid papulosis (LyP), carbamazepine-induced CD30+ pseudolymphoma, viral infection and an atypical eruption of lymphocyte recovery.     

CD30+ lymphoproliferative disorder with spindle‐cell morphology

Lymphomatoid papulosis (LyP) is classified as a CD30+ primary cutaneous lymphoproliferative disease. The phenotypic variability along the spectrum of CD30+ lymphoproliferative diseases is highlighted by the distinct histologic subtypes of LyP types A, B, C, and the more recently described types D, E, and F. We report the case of an elderly woman with a clinical presentation and histopathologic findings consistent with LyP, whose atypical CD30+ infiltrate uniquely demonstrated a spindle‐cell morphology. To our knowledge, this is the first reported case of LyP characterized by CD30+ spindle‐shaped cells, and may represent a new and distinct histologic variant of LyP.     

Homing receptor and chemokine receptor on intraepidermal T cells in psoriasis vulgaris

Intraepidermal T lymphocytes found in psoriatic skin lesions are involved in the development and maintenance of lesional pathology. It has become clear that differential expression of homing and chemokine receptors determines the specific migration of T cells to distinct tissues and microenvironments, including psoriasis lesions. The aim of the present study was to clarify expression of homing (CLA, VLA-4, and LFA-1) and chemokine (CCR4, CCR6, CCR7, and CXCR3) receptors on intraepidermal T cells in psoriatic lesions using flow cytometry. The vast majority of intraepidermal T cells in psoriatic lesions expressed CLA and LFA-1, whereas 58% of CD4+ and 85% of CD8+ T cells expressed VLA-4. The majority of CD4+ T cells and about half of the CD8+ T cells expressed CCR4 and CCR6, whereas less than one-third of CD4+ and CD8+ T cells expressed CXCR3 or CCR7. In patients with psoriasis the percentages of T cells expressing CLA, CCR4, and CCR6 were much higher in the epidermis of psoriatic plaques than in the peripheral blood. Thus, CLA, CCR4, and CCR6 may play a more important role in the migration of T cells to psoriatic epidermis.     

Iron deficiency and hair loss: the jury is still out

We report 3 cases of lymphomatoid papulosis (LyP) with a CD56+, cytotoxic immunophenotype. All 3 patients presented with clinical histories typical of LyP, with one patient having associated mycosis fungoides. Histologically, two cases were type A LyP and one was type B. All 3 cases demonstrated a T-cell receptor clone in lesional skin without evidence of blood involvement. The atypical lymphocytes in each of the 3 cases expressed cytotoxic granules (T-cell intracellular antigen-1+ and granzyme B+) and were CD8+ and CD56+. Expression of CD56 is associated with a poor prognosis in subcutaneous panniculitis-like T-cell lymphoma and blastic natural killer cell lymphoma. However, the two cases of CD56+ LyP previously reported and the 3 cases in this series all appear to be pursuing an indolent course with no evidence of systemic disease.     

Potential involvement of Notch1 signalling in the pathogenesis of primary cutaneous CD30-positive lymphoproliferative disorders

Background  The central role of Notch signalling in T‐cell development and oncogenesis raises the question of the importance of this pathway in cutaneous T‐cell lymphomas. Objectives  To investigate the pattern of expression of Notch and its ligands, Jagged and Delta, in skin samples of primary cutaneous CD30+ lymphoproliferative disorders. Methods  Immunohistochemistry of formalin‐fixed, paraffin‐embedded skin samples from 12 patients with lymphomatoid papulosis (LyP) and 11 patients with primary cutaneous anaplastic large cell lymphoma (ALCL). Immunofluorescence studies of fresh skin samples obtained from three patients with LyP and two patients with primary cutaneous ALCL. Results  We identified single Notch1‐positive cells or small clusters of atypical cells in LyP. Similarly, strongly positive Jagged1 cells tended to be localized in clusters. Primary cutaneous ALCL had higher expression of Notch1 and Jagged1 compared with LyP. Cells expressing Notch1 and Jagged1 were colocalized and a subset of cells expressed both the receptor and the ligand. The expression of the ligand Delta1 was low to undetectable in both types of lymphoproliferations. A subpopulation of lymphoma cells was found to coexpress Notch1 and activated Akt kinase. Conclusions  These results imply a potential role for the Notch signalling pathway in the pathogenesis of primary cutaneous CD30+ lymphoproliferative disorders and provide a rationale for the exploration of the activity of Notch antagonists in the therapy of these diseases.