Subcutaneous panniculitis-like T-cell lymphoma, lupus erythematosus profundus, and overlapping cases: molecular characterization through the study of 208 genes.

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare cytotoxic cutaneous lymphoma. Differential diagnosis with lupus erythematosus panniculitis (LEP) can be challenging and overlapping cases have been described. In this study, we investigate whether gene expression profiling may or not identify markers that can be used to improve our understanding of the disease and to make a precise differential diagnosis. SPTCL, LEP, and overlapping cases were analyzed using a customized NanoString platform including 208 genes related to T-cell differentiation, stromal signatures, oncogenes, and tumor suppressor genes. Gene expression unsupervised analysis of the samples differentiated SPTCL from LEP samples. Most overlapping cases were clustered with LEP cases. Differentially expressed genes were observed when comparing SPTCL with LEP cases; and overlapping with LEP cases. Gene set enrichment analysis recognized gene sets defining each group. In conclusion, SPTCL and LEP have distinctive molecular profiles and the molecular background of overlapping cases more closely resembles LEP.

The presence of clusters of plasmacytoid dendritic cells is a helpful feature for differentiating lupus panniculitis from subcutaneous panniculitis-like T-cell lymphoma.

AIMS: Both lupus panniculitis (LP) and subcutaneous panniculitis-like T-cell lymphoma (SPTCL) are characterized by subcutaneous lobular lymphocytic infiltrates, and they are sometimes difficult to differentiate. Recently, plasmacytoid dendritic cells (PDCs) were found to be present in various types of cutaneous lupus erythematosus lesions, including LP, and are supposed to play important pathogenetic roles. The aim of this study was to investigate whether PDCs are differentially present in these two diseases and can be utilized to differentiate them. Conventional histopathological features were also compared. METHODS AND RESULTS: Initial biopsies from 21 LP and 11 SPTCL patients were analysed. Our results showed that the presence of lymphoid follicles, dermal mucin deposition and lack of moderate to marked nuclear atypia or adipocyte rimming were more suggestive of LP. Several distinct patterns of fat necrosis, i.e. hyaline/lipomembranous and fibrinoid/coagulative in LP and SPTCL, respectively, were also diagnostically useful. Also, clusters of PDCs were characteristically seen in LP lesions (17/21, 81%) but not in SPTCL lesions (2/11, 18.2%). In LP lesions, but not in SPTCL lesions, the presence of epidermal interface change correlated perfectly with the presence of PDCs in the papillary dermis. CONCLUSIONS: We conclude that the presence of clusters of PDCs and certain histological features are helpful for the differential diagnosis.

Lupus erythematosus panniculitis: clinicopathological, immunophenotypic, and molecular studies.

Lupus erythematosus panniculitis (LEP) is an inflammatory disorder of the subcutaneous fat in patients with lupus erythematosus (LE). It is a rare variant of the disease, which occurs approximately in 1%-3% of patients with cutaneous LE. The purpose of this study was to investigate the clinical, histopathologic, immunophenotypical, and molecular profiles of LEP. We performed a retrospective study of 19 biopsy specimens from 17 patients with LEP. We reviewed their clinical data and reexamined the histopathology. Immunophenotyping and molecular studies were done using sections from paraffin-embedded formalin-fixed tissue. The most common clinical manifestation was a depressed patch on upper arm. Patients showed good response to variable treatment modalities, but, generally, relapse of panniculitis was noted when treatment was discontinued. Histopathologically, most specimens revealed lymphoplasmacytic lobular panniculitis with epidermal and dermal changes of LE, hyaline fat necrosis, and lymphoid follicles. Immunohistochemistry showed a mixture of T and B cells in dermis and subcutis with a slight preponderance of T cell. Although the polymerase chain reaction analysis of the T-cell receptor-gamma gene rearrangement showed a polyclonal smear in 89.5% of cases, a small portion of specimens demonstrated monoclonality. LEP is a chronic recurrent disease with characteristic features. Its diagnosis is often challenging, and a precise diagnosis is achievable only upon elaborate clinicopathologic correlation and integrated interpretation of all diagnostic criteria.

A case of lupus erythematosus profundus with unusual manifestations.

We describe a 16-year old female with lupus erythematosus panniculitis with unusual manifestations. She had noted to have developed erythematous nodules and plaques in the right axilla and inguinal region at the age of one year. These lesions resolved gradually with scar formation. However, new lesions were noted at the same locations in the following years. Some of her lesions at the scalp and the left axillary regions developing within the last two years slowly enlarged showing an annular configuration and subsequently resulted in hair loss. The erythematous border of her lesion in the left axilla consisted of two parallel red lines. Histopathological and direct immunofluorescent findings were consistent with lupus erythematosus panniculitis. Similar clinical findings in the same locations were also observed in the mother.

Atypical lymphocytic lobular panniculitis.

BACKGROUND: Although subcutaneous T-cell lymphoma (SCTCL) is considered an aggressive form of lymphoma, some patients manifest a long waxing and waning phase unaccompanied by constitutional symptoms. METHODS: Twelve patients were prospectively encountered, presenting with a lymphocytic panniculitis accompanied by lymphoid atypia, although not fulfilling criteria for SCTCL. Clinical, histologic, phenotypic, and genotypic analyses were conducted. RESULTS: There were five men, one boy, and six women; none had symptoms compatible with lupus erythematosus or aggressive SCTCL. All but two had a waxing and waning course of years. Four patients had periodic cytopenias accompanied by fevers. While responding somewhat to prednisone, the lesions relapsed. In one patient, treatment with alemtuzumab (CAMPATH-1) led to complete lesional resolution with no recurrence. Light microscopy showed expansion of the interstices of the fat lobule by mildly atypical lymphocytes of the CD4 subset in 10 biopsies from eight patients; in the other four patients, there was an increase in CD8 lymphocytes. There was diminished expression of CD5 and/or CD7 in the majority of biopsies. Ten of 13 biopsies showed clonal T-cell receptor-gamma rearrangements. CONCLUSIONS: We apply the term atypical lymphocytic lobular panniculitis to this distinctive form of lymphocytic panniculitis manifesting this light microscopic, phenotypic, and genotypic profile.

Lupus-like panniculitis in a patient with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED).

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare autosomal recessive disorder, characterised by a loss of self-tolerance to endocrine tissues, chronic candidiasis and ectodermal disorders. APECED is associated with mutations of a single gene, designated autoimmune regulator (AIRE). We describe a 31-year-old APECED patient with non-traumatic, cutaneous ulcers on both forearms with features of a lupus-like panniculitis. On admission to the ICU in September 2001, the patient suffered from a ketoacidotic, hyperglycemic coma and adrenal crisis due to an Enterobacter-cloacae sepsis, originating from multiple, necrotising deep cutaneous ulcers. These ulcers spontaneously developed on both forearms, some of which were just emerging, full blown or healing with scars. Histological examination showed signs of a scarring panniculitis and vasculitis. Immunohistochemistry and direct immunofluorescence with characterisation of immunoglobulin and complement-factor binding pattern revealed features of a lupus-like panniculitis. Sequence analysis of all 14 exons of the AIRE gene revealed a R257 X mutation in exon 6 resulting in a nonsense mutation at codon 257 confirming the diagnosis of APECED. Oral treatment with 60 mg/day corticosteroids for two weeks led to complete resolution of all ulcers. In conclusion, mutations in the AIRE gene may provide the genetic background against which additional factors can initiate an autoimmune process. Here, autoimmune panniculitis appears to be an associated feature of the APECED syndrome. Our findings support the use of immunosuppressive therapy for autoimmune disease components of the APECED syndrome.

Lupus erythematosus panniculitis: a clinicopathologic study.

BACKGROUND: Lupus erythematosus panniculitis is a clinical variant of lupus erythematosus which involves the deep dermis and the subcutaneous fat. The purpose of this study was to ascertain the clinical profile of Asian patients with this condition. METHODS: This was a retrospective study of all histologically confirmed lupus panniculitis seen at our center between 1992 and 1997. The age, sex, past history/subsequent diagnosis of systemic lupus erythematosus (SLE), presence of clinical discoid lupus erythematosus (DLE) changes on overlying skin, direct immunofluorescence, serologic, and histologic findings were analyzed. RESULTS: There were 12 cases of lupus panniculitis, two of which were in patients already diagnosed with SLE and one in which the patient subsequently evolved into SLE. The mean age at diagnosis was 31.3 years. The face (50%), upper limbs (33%), and scalp (25%) were the most common sites of involvement. Thirty-three per cent had clinical evidence of DLE on the overlying skin, whilst 67% had histologic features of DLE on the overlying skin. A lupus band was present in 36%. Antinuclear antibody (ANA) was positive in three of 11 cases; these were in the two patients who already had SLE and in the only patient who progressed to SLE. All of the cases showed fat necrosis and, in the majority of cases, there was associated lobular and paraseptal inflammation. Thirty-three per cent showed lymphocytic vasculitis and 75% had mucin deposition. None had lymphoid nodules, subepidermal hyalinization, or calcification. CONCLUSIONS: Lupus panniculitis affects a younger age group in Asians as compared with the Western population. Although about one-third of patients show clinical evidence of overlying DLE, two-thirds of patients show histologic evidence of DLE. It tends to have a mild disease course in the majority of cases.

Lupus profundus, indeterminate lymphocytic lobular panniculitis and subcutaneous T-cell lymphoma: a spectrum of subcuticular T-cell lymphoid dyscrasia.

INTRODUCTION: The diagnosis and classification of lymphocytic lobular panniculitis (LLP) has historically proven to be a difficult challenge. We encountered 32 cases of primary LLP which could be categorized as: 1) lupus erythematosus profundus (LEP) (19 patients); 2) an indeterminate group termed indeterminate lymphocytic lobular panniculitis (ILLP) (6 patients); and 3) subcutaneous T-cell lymphoma (SCTCL) (7 patients). OBJECTIVE: We attempted to better define the subtypes of LLP by morphologic, phenotypic and genotypic features and to correlate those features to clinical presentation and outcome. METHOD: Skin biopsy material was studied by conventional light microscopy, through immunophenotyping performed on sections from paraffin-embedded, formalin-fixed tissue and in some cases on sections of tissue frozen after receipt in physiological (Michel's) medium, and by polymerase chain reaction single-stranded conformational polymorphism analysis to assess for clonality of T-lymphocytes. Clinical features were correlated to histologic, phenotypic, and genotypic analyses. RESULTS: Patients with LEP had a prior diagnosis of LE or overlying skin changes which light microscopically were characteristic of LE. Patients with ILLP had no concurrent or prior history of LE, no systemic symptoms or cytopenias, and a clinical course not suggestive of lymphoma. Cases of SCTCL showed hemophagocytic syndrome and/or lesional progression with demise attributable to the disease. Lesions in all groups showed proximal extremity predilection. Females predominated in the LEP group. The average age of onset was 38, 40 and 55 years in the LEP, ILLP and SCTCL groups, respectively. Cytopenia was seen in 4 LEP patients; 1 also developed fever. In LEP and ILLP, lesions resolved with hydroxychloroquine and/or steroid therapy, with recurrences following cessation of therapy. In the SCTCL group 4 developed hemophagocytic syndrome, 4 died within 2 years of diagnosis, and 3 went into remission following chemotherapy. The LEP and SCTCL groups manifested histological similarities: dense perieccrine and lobular lymphocytic infiltration, lymphoid atypia, histiocytes with ingested debris, eosinophilic necrosis of the fat lobule and thrombosis. The atypical lymphocytes although pleomorphic did not have a cerebriform morphology. The infiltrate in ILLP had a similar cytomorphology and distribution with variable angioinvasion which in all save one case was of lesser intensity and was not associated with significant fat necrosis or vasculitis. Germinal centers, dermal/subcuticular mucin deposition and an atrophying interface dermatitis with hyperkeratosis and follicular plugging were largely confined to the LEP group. Erythrophagocytosis, characteristic of SCTCL, usually indicated a supervening subcuticular lymphoid dyscrasia when encountered in ILLP and LEP. SCTCL showed a selective loss of CD5 expression with or without diminution in CD7 and monoclonal CD3 expression. Of 4 cases studied, 3 showed a CD8 dominant infiltrate while 2 others exhibited CD56 and CD30 positivity, respectively. All cases of SCTCL with amplifiable DNA showed T-cell clonality. Similar molecular and phenotypic features indicative of subcuticular lymphoid dyscrasia were encountered in cases of LEP and ILLP including a reduction in CD5, CD7, and/or monoclonal CD3 expression, a preponderance of CD8 lymphocytes within the subcutaneous fat and T-cell clonality. These cases showed lymphoid atypia with variable erythrophagocytosis. Cases of phenotypically abnormal and/or clonal LEP showed one or more of local destruction, lesional size progression, fever, and cytopenias, but lesions responded to hydroxychloroquine and/or prednisone therapy and death attributable to panniculitis could not be documented. Cases that were phenotypically normal and without clonality had none of the aforesaid atypical clinical features. CONCLUSION: Lymphoid atypia, erythrophagocytosis, loss of certain pan T-cell markers, a reduced CD4/8 ratio and TCR rearrangement define subcuticular T-cell lymphoid dyscrasia, including a subset of LEP and ILLP. The subcuticular lymphoid infiltrates represent a spectrum of histologic, immunophenotypic, and molecular abnormalities which range from those which are clearly benign to those which are clearly neoplastic, and also encompasses those cases which defy precise classification into the two aforesaid poles.

Lupus erythematosus profundus with partial C4 deficiency responding to thalidomide.

A female patient with disfiguring lupus erythematosus profundus (LEP) from the age of 13 years was found to have an isolated partial C4 deficiency, with reduced levels of both allotypes, C4A and C4B. A genetic basis for the hypocomplementaemia was confirmed by a family study of complement and HLA types which revealed heterozygous null alleles for C4A and C4B in the proband. Marked improvement in her cutaneous lesions occurred with thalidomide.