Radiotherapy as a Treatment Option for Local Disease Control in Primary Cutaneous Diffuse Large B-Cell Lymphoma, Leg Type.

BACKGROUND: Primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL, LT) is an aggressive lymphoma variant. Anthracycline-based chemotherapy with rituximab is recommended as first-line treatment. Radiotherapy (RT) has been considered as a therapeutic option for local disease control in patients with solitary or localized lesions. METHODS: We report the results of a retrospective analysis of PCDLBC, LT patients treated either with RT alone or with physician's decision as first-line treatment, aiming to assess disease progression and/or first recurrence in these treatment groups. RESULTS: We retrospectively analyzed 20 patients treated either with RT alone (n = 8) or with investigator's choice treatment (n = 12), which included chemotherapy alone or combined with local therapy (RT and wide local excision). Complete response (CR) was achieved in 8 patients from the first group and 9 patients from the second group, with 1 treatment failure. Six patients treated with RT alone progressed with a median time to progression (TTP) of 12.5 months. In the second group, 5 patients progressed with a median TTP of 5.2 months. RT showed good local disease control in both groups without any skin relapses during the follow-up period. CONCLUSION: RT as first-line monotherapy followed by watchful waiting did not significantly improve the overall risk of disease progression but resulted in good local disease control. After progression, RT could still easily be combined with systemic treatment. The strength of this analysis needs to be evaluated in a larger patient cohort.

Blockade of programmed cell death protein 1 (PD-1) in Sézary syndrome reduces Th2 phenotype of non-tumoral T lymphocytes but may enhance tumor proliferation.

Sézary syndrome (SS) is an aggressive leukemic variant of cutaneous T-cell lymphoma (L-CTCL) that arises from malignant clonally derived skin-homing CD4+ T cells. Based on advancements in our understanding of the mechanisms underlying L-CTCL, boosting the suppressed immune response emerges as a promising strategy in SS management. Immune checkpoint inhibitory molecules have already demonstrated efficacy in a wide spectrum of malignancies. Currently, agents targeting the programmed death-1 (PD-1) axis are under evaluation in L-CTCL. Here we investigated the expression of PD-1 and its ligands, PD-L1 and PD-L2 in blood and skin from patients with L-CTCL. We demonstrate that PD-1 expression is markedly increased on tumor T cells compared to non-tumor CD4+ T cells from SS patients and to CD4+ cells from healthy individuals. In contrast, PD-L1 shows decreased expression on tumor T cells, while PD-L2 expression is low without significant differences between these groups. Functional PD-1 blockade in vitro resulted in reduced Th2 phenotype of non-tumor T lymphocytes, but enhanced the proliferation of tumor T cells from SS patients. Our study sheds some light on the PD-1 axis in both peripheral blood and skin compartments in SS patients, which may be relevant for the treatment of L-CTCL with immune checkpoint inhibitor.

Proteomic identification of a marker signature for MAPKi resistance in melanoma.

MAPK inhibitors (MAPKi) show outstanding clinical response rates in melanoma patients harbouring BRAF mutations, but resistance is common. The ability of melanoma cells to switch from melanocytic to mesenchymal phenotypes appears to be associated with therapeutic resistance. High-throughput, subcellular proteome analyses and RNAseq on two panels of primary melanoma cells that were either sensitive or resistant to MAPKi revealed that only 15 proteins were sufficient to distinguish between these phenotypes. The two proteins with the highest discriminatory power were PTRF and IGFBP7, which were both highly upregulated in the mesenchymal-resistant cells. Proteomic analysis of CRISPR/Cas-derived PTRF knockouts revealed targets involved in lysosomal activation, endocytosis, pH regulation, EMT, TGFß signalling and cell migration and adhesion, as well as a significantly reduced invasive index and ability to form spheres in 3D culture. Overexpression of PTRF led to MAPKi resistance, increased cell adhesion and sphere formation. In addition, immunohistochemistry of patient samples showed that PTRF expression levels were a significant biomarker of poor progression-free survival, and IGFBP7 levels in patient sera were shown to be higher after relapse.

Early clinical manifestations of Sézary syndrome: A multicenter retrospective cohort study.

BACKGROUND: Classic Sézary syndrome (SS) is defined by erythroderma, generalized lymphadenopathy, and leukemic blood involvement. Clinical observations suggest that SS begins as a nonerythrodermic disease. OBJECTIVE: To describe the early clinical characteristics of patients with SS. METHODS: A retrospective, multicenter chart review was performed for 263 confirmed cases of SS diagnosed during 1976-2015. RESULTS: Erythroderma was the earliest recorded skin sign of SS in only 25.5% of cases, although most patients (86.3%) eventually developed erythroderma. In patients without erythroderma during their initial visit, the first cutaneous signs of SS were nonspecific dermatitis (49%), atopic dermatitis-like eruption (4.9%), or patches and plaques of mycosis fungoides (10.6%). The mean diagnostic delay was 4.2 years overall, 2.2 years for cases involving erythroderma at the initial presentation, and 5.0 years for cases not involving erythroderma at the initial presentation. LIMITATIONS: This study is retrospective. CONCLUSION: Erythroderma is uncommon as an initial sign of SS. Early SS should be considered in cases of nonerythrodermic dermatitis that is refractory to conventional treatments. In these cases, examination of the blood by PCR for monoclonal T-cell receptor rearrangement and by flow cytometry to identify an expanded or aberrant T-cell population should be considered.

Sézary Syndrome and Atopic Dermatitis: Comparison of Immunological Aspects and Targets.

Sézary syndrome (SS), an aggressive form of erythrodermic pruritic cutaneous T cell lymphoma (CTCL), from an immunological perspective characterized by increased Th2 cytokine levels, elevated serum IgE and impaired cellular immunity. Not only the clinical appearance but also the hallmark immunological characteristics of SS often share striking similarities with acute flares of atopic dermatitis (AD), a common benign chronic inflammatory skin disease. Given the overlap of several immunological features, the application of similar or even identical therapeutic approaches in certain stages of both diseases may come into consideration. The aim of this review is to compare currently accepted immunological aspects and possible therapeutic targets in AD and SS.

Interleukin-1 receptor antagonist (anakinra) for Schnitzler syndrome.

Schnitzler syndrome is a rare autoinflammatory disease, which is defined by the presence of two major criteria: chronic urticaria and monoclonal immunoglobulin M (IgM) or immunoglobulin G gammopathy, in combination with at least two additional minor criteria: recurrent fever, leukocytosis and/or elevated C-reactive protein (CRP), objective signs of abnormal bone remodelling and a neutrophilic infiltrate in skin biopsy. We report on a 68-year-old female patient with a 10-year medical history of chronic urticaria, recurrent fever, severe arthralgia and increased CRP. Over the years, multiple diagnostic investigations were performed without conclusive findings, and therapeutic attempts with anti-histamines and several immunosuppressive agents had failed. The decision to initiate monotherapy with interleukin-1 (IL-1) receptor antagonist was based on immunohistochemical detection of the abundance of IL-1ß positive cells in the patient's skin biopsy. After starting treatment with anakinra, disappearance of symptoms could be observed within 24 h. Discontinuation of the treatment resulted in a rapid relapse of the symptoms. Finally, already after the initiation of therapy with anakinra, the suspected diagnosis of Schnitzler syndrome could be confirmed by detection of IgM-gammopathy that was initially absent.

Expression of CD164 on Malignant T cells in Sézary Syndrome.

Sézary syndrome is a primary cutaneous T-cell lymphoma characterized by pruritic erythroderma, peripheral lymphadenopathy and the presence of malignant T cells in the blood. Unequivocal detection of malignant cells in patients with Sézary syndrome is of important diagnostic, prognostic and therapeutic value. However, no single Sézary syndrome specific cell surface marker has been identified. In a cohort of patients with Sézary syndrome, CD164 expression on total CD4+ lymphocytes was significantly upregulated compared with healthy controls. CD164 expression was in most cases limited to CD4+CD26- malignant T lymphocytes, unequivocally identified using flow-cytometry by the expression of a specific Vß clone for each patient. Increased expression of CD164 may be a promising diagnostic parameter and a potential target for a CD164-linked therapeutic approach in Sézary syndrome.