The new World Health Organization-European Organization for Research and Treatment of Cancer classification for cutaneous lymphomas: a practical marriage of two giants
ABSTRACT Following consensus meetings of the two parent organizations, a new World Health Organization-European Organization for Research and Treatment of Cancer (WHO-EORTC) classification for primary cutaneous lymphomas has recently been published. This important development will now end the ongoing debate as to which of these was the preferred classification. The new classification will facilitate more uniformity in diagnosis, management and treatment of cutaneous lymphomas. In particular, it provides a useful distinction between indolent and more aggressive types of primary cutaneous lymphoma and provides practical advice on preferred management and treatment regimens. This will thereby prevent patients receiving high-grade treatment for low-grade biological disease. This review focuses on those diseases which have found new consensus agreement compared with the original WHO and EORTC classifications. In cutaneous T-cell lymphomas, these include folliculotropic mycosis fungoides, defining features of Sézary syndrome, primary cutaneous CD30+ lymphoproliferative disorders (primary cutaneous anaplastic large cell lymphoma, lymphomatoid papulosis and borderline lesions) and subcutaneous panniculitis-like T-cell lymphoma. Primary cutaneous CD4+ small/medium-sized pleomorphic T-cell lymphoma, primary cutaneous aggressive epidermotropic CD8+ T-cell lymphoma and cutaneous gamma/delta T-cell lymphoma are allocated provisional entry status and thereby afford better definitions for some cases of currently unspecified primary cutaneous peripheral T-cell lymphoma. In cutaneous B-cell lymphomas, diseases which have found new consensus agreement include primary cutaneous marginal zone B-cell lymphoma, primary cutaneous follicular centre lymphoma, primary cutaneous diffuse large B-cell lymphoma, leg type and primary cutaneous diffuse large B-cell lymphoma, other. CD4+/CD56+ haematodermic neoplasm (early plasmacytoid dendritic cell leukaemia/lymphoma) now appears as a precursor haematological neoplasm and replaces the previous terminology of blastic NK-cell lymphoma. Other haematopoietic and lymphoid tumours involving the skin, as part of systemic disease, will appear in the forthcoming WHO publication Tumours of the Skin. The new classification raises interesting new problems and questions about primary cutaneous lymphoma and some of these are discussed in this article. It is, however, a splendid signpost indicating the direction in which research in cutaneous lymphoma needs to go. In the interim, we have an international consensus classification which is clinically meaningful.
- SourceAvailable from: Jean Feuillard[Show abstract] [Hide abstract]
ABSTRACT: CD4(+)/CD56(+) haematodermic neoplasm or 'early' plasmacytoid dendritic cell leukaemia/lymphoma (pDCL) was described as a disease entity in the last World Health Organisation/European Organisation for Research and Treatment of Cancer classification for cutaneous lymphomas. These leukaemia/lymphomas co-express CD4 and CD56 without any other lineage-specific markers and have been identified as arising from plasmacytoid dendritic cells. Despite a fairly homogeneous pattern of markers expressed by most pDCL, numerous distinctive features (e.g. cytological aspects and aberrant marker expression) have been reported. This may be related to the 'lineage-independent developmental' programme of dendritic cells, which may be able to develop from either immature or already committed haematopoietic progenitors. This highlights the need for specific validated markers to diagnose such aggressive leukaemia. Here, we propose--among others (e.g. T-cell leukaemia 1)--blood dendritic cell antigen-2 and high levels of CD123 expression as potential markers. In addition, we propose a multidisciplinary approach including several fields of haematology to improve pDCL diagnosis.British Journal of Haematology 03/2007; 136(4):539-48. DOI:10.1111/j.1365-2141.2006.06458.x · 4.96 Impact Factor
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ABSTRACT: : Cutaneous lymphomas encompass a broad spectrum of malignancies, including both primary and secondary cutaneous lymphomas. Determining the exact subtype of cutaneous lymphoma offers prognostic importance and directs therapeutic decisions. We describe the case of a 67-year-old woman with cutaneous involvement of splenic marginal zone lymphoma successfully treated with rituximab and bendamustine. We discuss the diagnostic work-up, including the histopathologic findings and treatment of this disease.
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ABSTRACT: The production of high affinity antibodies is crucial in the combat of pathogenic invaders. Somatic hypermutation and class switch recombination are two DNA modifying processes that take place in the lymph node germinal centres, in order to increase antibody affinity and determine its effector function. However, recurrent subjection of B cells to these immunoglobulin gene alteration processes, due to chronic and recurrent infections or autoimmunity, may lead to accumulation of collateral DNA damage, this way increasing the risk of malignant derailment. This thesis deals with the molecular side of antibody diversification and its role in lymphomagenesis. A putative role for alternative splicing in the regulation of the enzyme responsible for the DNA modifications, i.e. activation-induced cytidine deaminase (AID), is investigated. Structure-function analysis of artificial AID mutants further substantiate this research. The significance of the B cell receptor and its antigen-specificity for lymphoma development, is explored by studying the immunoglobulin sequences of normal germinal centre and malignant lymphoma B cells. Biased immunoglobulin repertoires, in perspective to the genetic and environmental background of these tumours, provide insight in the origin and development of B cell malignancy.