Mycosis fungoides (MF) is primary cutaneous T-cell lymphoma (CTCL) characterized by cutaneous patches, plaques, tumors or erythroderma and histo-pathologically by a proliferation of atypical T lymphocytes within the skin. Sezary syndrome is a leukemic variant presenting with erythroderma. Cutaneous T-cell lymphomas are a family of extranodal lymphomas of mature T-cells, presenting in the skin. The revised staging system [Olsen et al 2007], classifies disease presentation in skin (T), lymph nodes (N), viscera (M) and blood (B). This TNMB classification stratifies patients into early stage (IA-IIA) and advanced stage (IIB-IVB) disease. Early stage carries a good prognosis with survival often exceeding 10 years. A third of patients present with advanced skin disease (T3-4) with median survivals of 35-56 months or nodal disease (median survival 13-25 months). Involvement of viscera is rare. Survival according to stage has been reported from centres with 5-year overall survival (OS) rates of 40-65% (IIB), 40-57% (III), 15-40% (IVA) and 0-15% (IVB) while at 10 years up to 40% of stage IIB and III patients were alive. In addition to stage, other potential prognostic markers have been identified in MF/SS. These include clinical features such as male gender and older age, elevated lactate dehydrogenase (LDH) and histologic features of folliculotropism (FT) and large cell transformation (LCT). Previous studies of prognostic factors have been mainly single-center and only a large scale international collaboration would allow the true impact of these factors to be defined. In addition to stage, other potential prognostic markers have been identified in MF/SS. These include clinical features such as male gender and older age, elevated lactate dehydrogenase (LDH) and histologic features of folliculotropism (FT) and large cell transformation (LCT) [Scarisbrick et all 2014]. Previous studies of prognostic factors have been mostly single center, and only a large scale international collaboration would allow the true impact of these factors to be defined.
The main objective of the PROCLIPI (Prospective Cutaneous Lymphoma International Prognostic Index) Study is to collect and share data on patients with cutaneous lymphoma. Cutaneous T cell lymphoma (CTCL) is recognized not only as a rare/orphan disease, but also a heterogeneous entity in clinical presentation, histopathology, and molecular features. The current staging does not accurately stratify patients according to survival. This study is aimed at identifying prognostic markers to develop a prognostic index, which will augment clinical staging and can be utilized for risk stratification in clinical management or therapeutic trials. Because of the rarity of this disease only an international collaboration will power such a study. To this end, the international community of experts in cutaneous lymphoma has formed an unprecedented large-scale collaborative alliance, the Cutaneous Lymphoma International Consortium (CLIC), to establish an efficient conduit where well defined prospective data are captured using a standard protocol.