Treatment of lymphocyte-predominant Hodgkin lymphoma.

Lymphocyte-predominant Hodgkin lymphoma (LPHL) was first described as Hodgkin’s paragranuloma by Jackson and Parker in 1944 [1]. Subsequently, a number of different terms such as lymphocytic-predominant Hodgkin’s disease or lymphocytic and histiocytic-predominant Hodgkin’s disease were used [2]. LPHL is rare, accounting for 5% of all Hodgkin lymphoma (HL) cases in western countries [3]. LPHL and classical HL (cHL) differ substantially in their histopathology and clinical cause. Histologically, LPHL can present with two distinct morphological patterns: nodular and diffuse. The nodular subtype is characterized by the presence of atypical lymphocytic and histiocytic (L&H) or popcorn cells that are embedded in a nodular background of small B lymphocytes and other reactive cells. In the diffuse subtype, the L&H cells are set against a diffuse background consisting mainly of reactive T cells. However, it remains controversial whether the diffuse subtype can be discriminated reliably. According to the current WHO definition, at least a partial nodular pattern is required for the diagnosis of NLPHL [4]. Compared with cHL, LPHL has been associated with less aggressive tumor growth and lymphadenopathy often preceding the diagnosis for many years [5]. Since the treatment of patients with LPHL results in complete remission (CR) in >95% of patients, the need for different treatment approaches particularly for early-stage patients has been questioned recently.