The aim of this study was retrospectively to assess the validity of the 2005 WHO-EORTC classification for primary cutaneous lymphomas (PCL) in a large cohort of patients of a single German skin cancer unit. All patients with PCLs consecutively visiting our hospital between January 1980 and December 2005 were included in a retrospective monocentre study, analysing their histological and clinical data. A total of 312 patients fulfilled the inclusion criteria for PCL. In 299 patients clinical information and paraffin material were sufficient for detailed classification. Of the 299 patients, 63% expressed a T-cell and 37% a B-cell phenotype. Mycosis fungoides was the entity with the highest frequency (30.9%), followed by primary cutaneous follicle centre lymphomas (16.9%) and lymphomatoid papulosis (15.9%). The mean follow-up period was 38.4 months. Five-year disease-specific survival was 80.5% for mycosis fungoides, 92.5% in primary cutaneous anaplastic large cell lymphoma, 100% in lymphomatoid papulosis, 98.1% in primary cutaneous follicle center lymphoma, 100% in primary cutaneous marginal zone lymphoma and 63.2% in diffuse large B-cell lymphoma, leg type. Our data are in line with the data collected by the WHO-EORTC. This is further evidence for the reliability of the WHO-EORTC classification and staging system.

No abstract

Transformation of MF to high grade lymphoma may be associated with the adoption of a regulatory T-cell phenotype. FOXP3 expression may contribute to aggressive behavior of MF after large cell transformation via immune escape mechanism. The significance of this observation is limited by the low case number in this study.

ESR has turned out as independent prognostic factor in mycosis fungoides.

For the modern evidence based medicine classification systems are necessary to guarantee a unifying approach for therapy and for prognosis of diseases. The comparability of clinical studies depends of the usage of adequate classification systems. But because all classifications are artificial, they only mirror the technical possibilities of its area.This review discusses the history of lymphoma classifications systems with a special focus on the topic of primary cutaneous lymphomas and the retikuloendothelial system. Furthermore special problems in terminology are discussed.clinical behavior and prognosis than histologically, cytomorphologically and immunohistochemically identical secondary cutaneous and nodal lymphomas [13]. However, for years the B-cell lymphomas in particular were divided into a classification system for nodal lymphomas which was partly not reproducible, resulting in serious consequences for treatment, which failed to meet the prognosis [13,14].