OBJECTIVETo study the diagnosis and the differential diagnosis of nodular lymphocyte-predominant Hodgkin's lymphoma (NLPHL).

METHODS245 cases of Hodgkin's lymphoma (HL) diagnosed between 1980 and 2000 from 3 hospitals in Guangzhou were reviewed. Four cases of NLPHL were confirmed according to the WHO classification of lymphoid neoplasms. Among the other 3 cases of NLPHL, 2 collected from other clinical centers and 1 from Fudan University Cancer Hospital. Immunohistochemistry (IHC) were performed on paraffin sections through SP technique using a panel of markers to define the large neoplastic cells (CD45, CD20, CD15, CD30 and vimentin) as well as the non-neoplastic background cells (CD3, CD20, CD45RO, CD57, CD68 and TIA-1).

RESULTSSeven patients with NLPHL were 4 males and 3 females, age 29 to 70 years, average 43.8 years. All patients had lymphadenopathy. Histologically, in NLPHL, instead of the structure of normal lymph nodes, the tumor tissue became nodular in architecture. Characteristic lymphocytic and histiocytic (L&H) cells with scant cytoplasm and large multilobulated nuclei distributed among a predominant population of small lymphoid cells. The large cells exhibited a CD45+, CD20+, but CD15-, CD30- and vimentin-phenotype. The background cellularity was relatively rich in B cells and the majority of T-cells infiltrated were CD57(+) cells. TIA-1+ cells were few.

CONCLUSIONSNLPHL can be diagnosed according to the morphologic and immunophenotypic features rather than by morphology alone. It is important to distinguish this tumor from its morphologic mimics, such as lymphocyte-rich classical Hodgkin's lymphoma (LRCHL) and T-cell rich B-cell lymphoma (TCRBCL). The immunophenotype of neoplastic cells and background cells are the helpful criteria for the differential diagnosis.