Response to Chlormethine/Mechlorethamine gel Maintenance Treatment Regimen in Patients With Mycosis Fungoides: A Single-center Retrospective Study

Primary cutaneous lymphomas are a heterogeneous group of T- and B-cell lymphomas that present in the skin with no evidence of extracutaneous disease at the time of diagnosis. The 2005 World Health Organization–European Organization for Research and Treatment of Cancer (WHO-EORTC) consensus classification has served as a golden standard for the diagnosis and classification of these conditions. In September 2018, an updated version of the WHO-EORTC was published in the fourth edition of the WHO Classification of Skin Tumours Blue Book. In this classification, primary cutaneous acral CD8 + T-cell lymphoma and Epstein-Barr virus positive (EBV + ) mucocutaneous ulcer are included as new provisional entities, and a new section on cutaneous forms of chronic active EBV disease has been added. The term “primary cutaneous CD4 + small/medium T-cell lymphoma” was modified to “primary cutaneous CD4 + small/medium T-cell lymphoproliferative disorder” because of its indolent clinical behavior and uncertain malignant potential. Modifications have also been made in the sections on lymphomatoid papulosis, increasing the spectrum of histologic and genetic types, and primary cutaneous marginal zone lymphomas recognizing 2 different subtypes. Herein, the characteristic features of these new and modified entities as well as the results of recent molecular studies with diagnostic, prognostic, and/or therapeutic significance for the different types of primary cutaneous lymphomas are reviewed. An update of the frequency and survival of the different types of primary cutaneous lymphomas is provided.

Mycosis fungoides (MF) and Sézary syndrome (SS), the major forms of cutaneous T-cell lymphoma, have unique characteristics that distinguish them from other types of non-Hodgkin's lymphomas. Clinical trials in MF/SS have suffered from a lack of standardization in evaluation, staging, assessment, end points, and response criteria. Recently defined criteria for the diagnosis of early MF, guidelines for initial evaluation, and revised staging and classification criteria for MF and SS now offer the potential for uniform staging of patients enrolled in clinical trials for MF/SS. This article presents consensus recommendations for the general conduct of clinical trials of patients with MF/SS as well as methods for standardized assessment of potential disease manifestations in skin, lymph nodes, blood, and visceral organs, and definition of end points and response criteria. These guidelines should facilitate collaboration among investigators and collation of data from sponsor-generated or investigator-initiated clinical trials involving patients with MF or SS.

In order to provide a common standard for the treatment of mycosis fungoides (MF) and Sézary syndrome (SS), the European Organisation for Research and Treatment of Cancer-Cutaneous Lymphoma Task Force (EORTC-CLTF) published in 2006 its consensus recommendations for the stage-adapted selection of management options for these neoplasms. Since then, the understanding of the pathophysiology and epidemiology of MF/SS has advanced, the staging system has been revised, new outcome data have been published and novel treatment options have been introduced. The purpose of the present document is to update the original recommendations bearing in mind that there are still only a limited number of controlled studies to support treatment decisions for MF/SS and that often treatment is determined by institutional experience and availability. This consensus on treatment recommendations was established among the authors through a series of consecutive consultations in writing and a round of discussion. Recommended treatment options are presented according to disease stage, whenever possible categorised into first- and second-line options and supported with levels of evidence as devised by the Oxford Centre for Evidence-Based Medicine (OCEBM). Skin-directed therapies are still the most appropriate option for early-stage MF, and most patients can look forward to a normal life expectancy. For patients with advanced disease, prognosis is still grim, and only for a highly selected subset of patients, prolonged survival can be achieved with allogeneic stem cell transplantation (alloSCT). There is a high need for the development and investigation in controlled clinical trials of treatment options that are based on our increasing understanding of the molecular pathology of MF/SS.