Application of immunophenotypes in pathologic diagnosis of follicular lymphomas / 白血病·淋巴瘤

ABSTRACT

Objective To investigate the value of immunophenotypes in pathologic diagnosis of follicular lymphoma (FL) and the differential diagnosis between neoplastic follicle (NF) and reactive hyperplastic follicle (RHF).Methods 50 cases of FL and 10 cases of RHF as control were studied by clinical data, the expressions of CD20, bcl-2, CD3, CD10, bcl-6, CD21 and Ki-67 were detected by EnVision immunohistochemical method for the immunphenotypical pattern of FL and RHF.Results Among 50 FL cases , there were 24 male cases and 26 female cases, with median age of 50 years old (10-80 years old), including 32 cases (64 ％) involved predominantly neck lymph nodes.The histologic grades were 1-2 in 16 cases (32 ％) and ≥3 in 34 cases (68 ％).CD20, CD10 and bcl-6 were positive in NF tissues of FL, with irregular forms of NF and loss of the mantle area without clear demarcation, and infiltrating to NF, irregular shape and no clear perimeter.The bcl-2 was positive in all of grade 1-2 NF, and it was positive in 68 ％ (23/34) cases and was partial or total negative in 32 ％ (11/34) cases in grade≥3 NF.Those were poorly demarcated contours.The Ki-67 proliferative index of NF were ＜30 ％ in grade 1-2, and ＞30 ％ in grade ≥ 3, with the highest to 90 ％.In FL, the CD21 staining result showed follicular dendritic cells (FDC) network were synchronized with NF, and in some cases of grade ≥ 3, the FDC network were ruptured.In RHF, the CD20 was positive for round or oval nodules with clear demarcation.The CD10, bcl-6 and CD21 were positive and bcl-2 was negative in all germinal center without invasive immunophenotype.The Ki-67 index was high in germinal center, and sometimes polarity may be seen.Conclusion The immunophenotypical differences between FL and RHF include invasive characteristics, loss of follicular mantle area and germinal center pattern in the NF, while the normal follicular immunophenotype in the RHF.