[The history of lymphoma classifications with special consideration of cutaneous lymphomas].

For modern evidence-based medicine, classification systems are necessary to guarantee a uniform approach for therapy and for estimating prognosis. The comparability of clinical studies and international communication require a common language and are only possible with modern international classification systems. But because all classifications are artificial, they only mirror the current state of knowledge and may change dramatically over decades. This review discusses the history of lymphoma classifications systems with a special focus on the topic of primary cutaneous lymphomas, emphasizing special problems in terminology.