Panniculitic primary cutaneous gamma delta T-cell lymphoma with concomitant features of autoimmune disease emphasizing a pathophysiologic continuum of lupus profundus with the panniculitic T cell lymphomas.

Certain T-cell lymphomas exhibit unique homing properties of the neoplastic lymphocytes for the subcutaneous fat. There are two primary forms of subcutaneous panniculitic lymphomas of T-cell origin. One falls under the designation of primary cutaneous gamma-delta T-cell lymphomas (PGD-TCL) whereby there is dominant involvement of the fat defininng a panniculitic form of PGD-TCL. The neoplastic cells are of the gamma-delta subset and are either double negative for CD4 and CD8 and/or can express CD8. They often have an aggressive clinical course. The other form of panniculitic T-cell lymphoma falls under the designation of subcutaneous panniculitis-like T-cell lymphoma (SPTCL). It represents a subcutaneous lymphoma derived from CD8+ T cells of the alpha-beta subset and typically has an indolent course. These two forms of panniculitic T-cell lymphoma exhibit overlapping histologic features with lupus profundus (LP), a putative form of panniculitic T-cell dyscrasia. We present three cases of PGD-TCL of the fat in the setting of lupus erythematosus (LE) (two cases) and dermatomyositis (DM) (one case), respectively. There were concurrent features of LE and DM in their lymphoma biopsies in two cases while a prior biopsy in one was interpreted as LP. In this latter case, the LP diagnosis presaged the diagnosis of panniculitic PGD-TCL by three years. One patient diagnosed with panniculitic PGD-TCL had hemophagocytic syndrome after developing a lupus-like complex including certain supportive serologies such as antibodies to double-stranded DNA following initiation of statin therapy. The second patient presented with PGD-TCL and concomitant features of anti-nuclear matrix 2 (NXP2) DM. The third patient presented in 2003 with LP and overlying skin features of acute LE, initially responding to Plaquenil, and then four years later was diagnosed with PGD-TCL heralded by Plaquenil treatment resistance. Two of the patients died of their lymphoma. All biopsies showed a characteristic histopathology of PGD-TCL. In two cases, the PGD-TCL was associated with overlying LE-cutaneous findings; another case had skin changes of lymphocyte-rich DM. In two cases, the MXA stain was strikingly positive, the surrogate type I interferon marker that is typically upregulated in biopsies of LE and DM. There are eight prior reported cases describing SPTCL with concomitant cutaneous changes of LE. In six cases there was an established history of LE, including LP responding initially to Plaquenil, similar to one of our cases. In the context of SPTCL or panniculitic PGD-TCL, panniculitic T-cell lymphomas can be associated with concomitant clinical and histologic features of LE or DM, including an upregulated type I interferon signature. Identifying histologic features associated with either of these prototypic autoimmune conditions should not be considered exclusionary to diagnosing any panniculitic T-cell lymphoma. A clinical, histomorphologic, and pathophysiologic continuum exists with LP, SPTCL and panniculitic PGD-TCL.

IRF8 in Conjunction With CD123 and CD20 to Distinguish Lupus Erythematosus Panniculitis From Subcutaneous Panniculitis-like T-Cell Lymphoma.

Distinguishing lupus erythematosus panniculitis (LEP) from subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a diagnostic challenge with important clinical implications. Immunohistochemical expression of interferon regulatory factor 8 (IRF8) has been shown to highlight cells with plasmacytoid dendritic cell differentiation. Considering that the presence of plasmacytoid dendritic cells highlighted by CD123 immunolabeling is a well-described feature that supports LEP over SPTCL, we hypothesized that IRF8 immunohistochemistry can be used as a diagnostic test to improve accuracy in differentiating LEP from SPTCL. In this study, we assessed the expression of IRF8, CD123, and CD20 in 35 cutaneous biopsies from 31 distinct patients, which included 22 cases of LEP and 13 cases of SPTCL. We found that clusters of IRF8-positive cells within the dermis, and away from subcutaneous fat, could discriminate LEP from SPTCL ( P =0.005). Similarly, CD123-positive clusters in any location were observed in LEP but absent in all cases of SPTCL. In addition, we found that dermal CD20-predominant lymphoid aggregates could help discriminate LEP from SPTCL ( P =0.022). As individual assays, IRF8, CD123, and CD20 were highly specific (100%, 100%, and 92%, respectively) though poorly sensitive (45%, 29%, and 50%, respectively). However, a panel combining IRF8, CD123, and CD20, with at least 1 positive marker was more accurate than any individual marker by receiver operating characteristic curve analysis. Our study provides a rationale for potentially including IRF8 as part of an immunohistochemical panel composed of other currently available markers used to differentiate LEP from SPTCL.

Linear and Annular Lupus Panniculitis of the Scalp.

This case report describes hair loss in a linear pattern toward the frontal scalp, with associated erythema on left forehead.

[Characteristics of the course of lupus erythematosus panniculitis in a retrospective analysis of 17 patients]. / A lupus erythematosus panniculitis lefolyásának jellegzetességei 17 betegünk retrospektív vizsgálata alapján.

INTRODUCTION: Lupus erythematous panniculitis (LEP) is a rare type of chronic cutaneous lupus erythematous. Clinical characteristics are tender, subcutaneous nodules, erythematous plaques. Disfigurement of face and body might develop which affects the patient's quality of life. LEP can be the first sign of systemic lupus erythematous (SLE). OBJECTIVE: Our aim was to review the clinicopathological characteristics and the course of LEP through our own patients. METHODS: We retrospectively analyzed the clinical records of 17 LEP patients at Semmelweis University's Department of Dermatology, Venerology and Dermatooncology between 2000 and 2022. RESULTS: The male : female ratio was 1 : 16, average age was 37.8 years. Lesion localisations were proximal lower (8/17) and upper extremities (7/17), face (4/17), breast (3/17), chest (2/17), buttocks (2/17), back (1/17) and distal lower extremity (1/17). Lesion morphologies were nodules (11/17), plaques (7/17), lipoatrophy (4/17), ulceration (3/17), calcification (1/17). Discoid changes covered in 6 cases. In 10 cases, systemic symptoms were observed (arthritis (4/17), haematological (5/17), renal (2/17), anti-phospholipid syndrome (2/17). 7 patients fulfilled the EULAR/ACR criteria for SLE. Histology showed mixed type panniculitis in 8, lobular in 3 cases. Average time until diagnosis was 24.3 months. Among all our SLE patients, skin symptoms regressed following systemic immunosuppressive treatment. LEP patients with only skin manifestation were often resistant for the therapy of cutaneous lupus erythematous. CONCLUSION: The diagnosis of LEP often takes months or years. Wider knowledge of LEP would shorten the time to diagnosis, preventing disfigurement and possible damage of internal organs. Based on our observations, LEP without SLE might be treated with early immunosuppression. Orv Hetil. 2023; 164(5): 172-178.

Orbital Mass as the Only Presenting Sign with Overlapping Features of Lupus Erythematosus Panniculitis and Subcutaneous Panniculitis-Like T-Cell Lymphoma.

PURPOSE: Even though subcutaneous panniculitis-like T-cell lymphoma (SPTCL) and lupus erythematosus panniculitis (LEP) are two separate entities, recently they were claimed to represent two ends of a spectrum of T-cell-mediated orbital lymphoproliferative diseases. METHODS: A 78-year-old woman presented with a 1-month history of right-sided periorbital swelling and redness. There was a palpable mass in the medial right lower eyelid with restriction of upward and lateral gaze. MRI revealed a 14 × 7 mm hypointense lesion in the anteromedial orbit. RESULTS: The systemic and ocular findings, orbital biopsy with histopathology and immunochemistry showed overlapping features of LEP and SPTCL. The patient was consulted with rheumatology and hematology, and the physicians arrived at a consensus that the patient existed in the above-mentioned disease spectrum. She was started on systemic immunosuppressive treatment and her clinical findings improved substantially. CONCLUSIONS: This is the first report of a patient, who presented with orbital mass causing vision loss and gaze restriction that had overlapping clinical and histopathologic features of LEP and SPTCL consistent with this novel disease spectrum, in the literature.

Subcutaneous Panniculitis-like T-cell Lymphoma with a HAVCR2 Mutation Diagnosed after 10 Years of Treatment with Glucocorticoids and Cyclosporine as Lupus Panniculitis.

Subcutaneous panniculitis-like T cell lymphoma (SPTCL) is a very rare cutaneous T cell lymphoma that has been reported to be associated with autoimmune disorders but is most commonly associated with systemic lupus erythematosus. We herein report a 26-year-old man thought to have lupus panniculitis (LP) treated for 10 years with corticosteroids and cyclosporine. After several relapses with panniculitis, he was finally diagnosed with SPTCL, which was confirmed to have a HAVCR2 mutation for p.Tyr82Cys. We emphasize that rheumatologists should be aware of the possibility of SPTCL, despite its rare appearance, when making a diagnosis of LP or when encountering clinical manifestations that are not consistent with LP.

Centrifugal lipodystrophy on a spectrum with lupus erythematosus panniculitis in children and efficacy and safety of hydroxychloroquine: A clinicopathological study.

This study aimed to investigate the relationship between centrifugal lipodystrophy (CLD) and lupus erythematosus panniculitis (LEP), and the efficacy and safety of hydroxychloroquine (HCQ) for treating CLD in children. A total of 29 cases clinically diagnosed as CLD (n = 24) and CLD/LEP overlap (n = 5) were enrolled and all were confirmed by skin biopsies of CLD and LEP. The clinicopathological findings, clinical outcomes, and prognosis with the treatment of HCQ between CLD and LEP were compared. All 29 cases (male: female = 1:1.6; median age at onset: 3 years) had cutaneous lesions of centrifugally expanding lipoatrophy, of which five cases overlapped with LEP lesions presented as erythematous indurated plaque (n = 2), subcutaneous nodules (n = 2) and alopecia along Blaschko's lines (n = 1). Antinuclear antibodies were found in six (25.0%) CLD and two (40.0%) overlapped patients (p = 0.597). Histopathologically, of the 24 cases of CLD, 14 (58.5%) exhibited subcutis loss or mild lobular inflammation. Ten (41.7%) cases displayed lobular panniculitis with moderate to dense lymphohistiocytic infiltrate and plasma cells, similar to the five cases of overlap. Small clusters of CD123 positive plasmacytoid dendritic cells were found in 62.5% (5/8) of CLD and 66.7% (2/3) of overlap cases (p > 0.99). HCQ (5 mg/kg/d) treatment showed improvement in 91.3% (21/23) of CLD and all overlap cases, including four cases unresponsive to previous oral glucocorticosteroid treatment. Our findings suggested that CLD and LEP represent a spectrum within the same disease. HCQ (5 mg/kg/d) was effective and safe for treating CLD (age >1.5 years), and early treatment and a regular long-term follow-up are essential.

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.

Kikuchi-Fujimoto disease preceded by lupus erythematosus panniculitis: do these findings together herald the onset of systemic lupus erythematosus?

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare disorder that must be distinguished from systemic lupus erythematosus (SLE). Although a minority of patients with KFD develop SLE, most patients have a self-limited disease. Importantly, KFD can have skin manifestations resembling cutaneous lupus. Therefore, the diagnosis of SLE should be predicated on a complete rheumatologic workup and not on the constellation of skin disease and lymphadenitis. Nonetheless, as our exceedingly rare case illustrates, patients who do not initially meet diagnostic criteria for SLE require dermatologic follow-up. We present a young adult woman who had a remote history of KFD and later presented with combined features of discoid lupus and lupus erythematosus panniculitis (LEP). On subsequent rheumatologic workup, she fulfilled criteria for SLE. We discuss the differential diagnosis of both KFD and LEP and emphasize how strong communication among dermatologists and other healthcare providers is essential in the management of patients with KFD.

Refractory lupus panniculitis treated successfully with rituximab: Two cases.

Lupus panniculitis is usually difficult to treat, and the patient is often put on multiple immunosuppressives with variable clinical response and relapses, notwithstanding the long-term side effects. We describe two cases of refractory lupus panniculitis which have been treated successfully with rituximab which is a chimeric anti-CD20 antibody. It reduces the number of circulating mature B-cells, thereby reducing the autoantibodies and the mediators of inflammation. Rituximab is a good alternative to patients who are not responsive to conventional treatment options for lupus panniculitis. There have been few side effects reported by the patients, but the clinical response and psychological well-being clearly outweigh them.

Résumé La panniculite lupique est généralement difficile à traiter et le patient est souvent soumis à plusieurs immunosuppresseurs avec une réponse clinique variable et les rechutes, malgré les effets secondaires à long terme. Nous décrivons deux cas de panniculite lupique réfractaire qui ont été traités rituximab qui est un anticorps anti-CD20 chimérique. Il réduit le nombre de cellules B matures en circulation, réduisant ainsi la les autoanticorps et les médiateurs de l'inflammation. Le rituximab est une bonne alternative aux patients qui ne répondent pas aux traitements conventionnels options de traitement pour la panniculite lupique. Les patients ont signalé peu d'effets secondaires, mais la réponse clinique et le bien-être psychologique les surpassent clairement.

Utility of CD123 immunohistochemistry in differentiating lupus erythematosus from cutaneous T cell lymphoma.

AIMS: Histopathological overlap between lupus erythematosus and certain types of cutaneous T cell lymphoma (CTCL) is well documented. CD123+ plasmacytoid dendritic cells (PDCs) are typically increased in lupus erythematosus, but have not been well studied in CTCL. We aimed to compare CD123 immunostaining and histopathological features in these conditions. METHODS AND RESULTS: Skin biopsies of cutaneous lupus erythematosus (CLE, n = 18), lupus erythematosus panniculitis (LEP, n = 17), mycosis fungoides (MF, n = 25) and subcutaneous panniculitis-like T cell lymphoma (SPTCL, n = 9) were retrospectively reviewed and immunostained with CD123. Percentage, distribution and clustering of CD123+ cells were compared between CLE and MF and between LEP and SPTCL using χ2 and two-tailed t-tests. A higher percentage of CD123+ cells was observed in CLE than MF (P < 0.01), more frequently comprising ≥20% of the entire infiltrate (P < 0.01) and forming clusters (P < 0.01). Similarly, LEP showed a higher percentage of CD123+ cells than SPTCL (P = 0.01), more frequently comprising ≥20% of the infiltrate (P = 0.04) and forming clusters (P = 0.01). Basal vacuolar change or dyskeratosis was observed in all CLE cases and in 48% cases of MF cases (P = 0.05). Plasma cells were readily identified in 76% cases of LEP but in none of the SPTCL cases (P = 0.01). Adipocyte rimming by lymphocytes, hyaline fat necrosis and fibrinoid/grungy necrosis did not significantly differ between LEP and SPTCL. Dermal mucin also failed to distinguish between groups. CONCLUSIONS: CD123 immunostaining is helpful in differentiating CLE from MF and LEP from SPTCL, but should be interpreted in conjunction with clinicopathological features and other ancillary studies to ensure accurate diagnosis.

Paniculitis lúpica: características clínico-patológicas de una serie de 12 pacientes / Lupus panniculitis: Clinicopathological features of a series of 12 patients

Antecedentes y objetivo: La paniculitis lúpica (PL) es una forma infrecuente de lupus eritematoso cutáneo crónico, cuyo diagnóstico requiere una adecuada correlación clínico-patológica, especialmente si constituye la primera manifestación de lupus eritematoso (LE). Dependiendo del estado evolutivo de las lesiones, la biopsia puede mostrar cambios poco específicos que dificultan el diagnóstico. Existen pocas series publicadas sobre esta entidad. Aportamos la experiencia de nuestro centro en su diagnóstico y manejo. Materiales y métodos: Estudio clínico-patológico retrospectivo descriptivo de 12 casos diagnosticados de PL en nuestro servicio. Resultados: Todos los pacientes tenían placas y/o nódulos dolorosos recurrentes, característicamente localizados en la zona proximal de las extremidades, la cara y el cuero cabelludo. En la biopsia había paniculitis de predominio lobulillar con infiltrados linfoplasmocitarios. Esto, junto con la coexistencia de otras manifestaciones clínicas de LE y el estudio de expresión de CD123, permitió establecer el diagnóstico de PL. En 3 pacientes la PL fue la primera manifestación de LE. Conclusiones: La PL es una entidad de difícil diagnóstico. La presencia de otras manifestaciones clínicas y/o histológicas de lupus y la utilización de técnicas inmunohistoquímicas pueden ser útiles para el diagnóstico diferencial con otras paniculitis

Background and objective: Lupus panniculitis (LP) is a rare variant of chronic cutaneous lupus erythematosus, which diagnosis requires clinicopathological correlation, especially in those patients without any other manifestation of lupus erythematosus (LE). According to the phase when the biopsy is performed, histological findings can be non-specific. Few series have been published to date. Hence, we report our own experience in the diagnosis and management of this disease. Materials and methods: We conducted a retrospective descriptive clinicopathological study of 12 patients diagnosed in our centre. Results: All the patients had painful and recurrent plaques and/or nodules, with a predilection for proximal extremities, face and scalp. Histopathologic examination showed mostly lobular panniculitis and lymphoplasmacytic infiltrate. For the diagnosis, we also considered the coexistence of other clinical manifestations of LE as well as the expression of CD123 by immunohistochemistry. In 3 patients, LP was the first manifestation of LE. Conclusions: The diagnosis of LP can be difficult. The presence of other clinical and/or histological manifestations of LE along with immunohistochemistry techniques could help in the differential diagnosis with other panniculitis