Sun T, Susin M, Koduru P, Dittmar K, Yannopoulos K, Mahapatro D, Rogers C
Department of Laboratories, North Shore University Hospital-Cornell University Medical College, Manhasset, New York 11030.
Hematol Pathol. 1992;6(4):179-92.
A case of composite lymphoma consisting of an anaplastic large-cell Ki-1 lymphoma and a small-cell follicular lymphoma was found in the splenic hilar lymph node of a 66-year-old woman. The Ki-1 lymphoma showed monoclonal IgM-lambda and CD 20, CD 74, and CDw 75 antigens by immunostaining and CD 19, CD 20, CD 22, and lambda antigens by flow cytometry. The follicular lymphoma also showed monoclonal IgM-lambda, and CD 20 and CDw 75 antigens but not CD 74 and CD 30 (Ki-1) by immunostaining. Flow cytometric analysis of the follicular lymphoma component was not conclusive, as it was impossible to separate the neoplastic from the normal small B lymphocytes. Ki-1 lymphoma usually is seen in childhood and is mostly of T cell origin. It is, therefore, unusual to find Ki-1 antigen component in a composite lymphoma of B-cell origin in an adult. However, there has been evidence to suggest that B-cell Ki-1 lymphoma may be related to follicular lymphoma. Thus, our case may represent a follicular lymphoma transforming into a Ki-1 lymphoma. Immunogenotyping in this case revealed that the two components were probably of the same clonal origin, as they seemed to share the same light chain gene. The presence of rearrangement in the switch region of the IgH in our case without the actual occurrence of heavy chain switching may have triggered somatic recombination in the IgH complex. This series of events may have led to the transformation of a low-grade lymphoma into a high-grade lymphoma, accounting for the two morphologic patterns seen in our bimorphic lymphoma.
在一名66岁女性的脾门淋巴结中发现了一例由间变性大细胞Ki-1淋巴瘤和小细胞滤泡性淋巴瘤组成的复合性淋巴瘤。Ki-1淋巴瘤经免疫染色显示单克隆IgM-λ以及CD20、CD74和CDw75抗原，经流式细胞术检测显示CD19、CD20、CD22和λ抗原。滤泡性淋巴瘤经免疫染色也显示单克隆IgM-λ以及CD20和CDw75抗原，但不显示CD74和CD30（Ki-1）。滤泡性淋巴瘤成分的流式细胞术分析结果不明确，因为无法将肿瘤性小B淋巴细胞与正常小B淋巴细胞区分开。Ki-1淋巴瘤通常见于儿童期，大多起源于T细胞。因此，在一名成人的B细胞起源复合性淋巴瘤中发现Ki-1抗原成分是不寻常的。然而，有证据表明B细胞Ki-1淋巴瘤可能与滤泡性淋巴瘤有关。因此，我们的病例可能代表了滤泡性淋巴瘤向Ki-1淋巴瘤的转化。该病例的免疫基因分型显示，这两种成分可能起源于同一克隆，因为它们似乎共享相同的轻链基因。在我们的病例中，免疫球蛋白重链（IgH）转换区存在重排，但未实际发生重链转换，这可能触发了IgH复合体中的体细胞重组。这一系列事件可能导致了低级别淋巴瘤向高级别淋巴瘤的转化，解释了我们的双形态淋巴瘤中所见的两种形态学模式。
