Fujimoto J, Hata J, Ishii E, Kiyokawa N, Tanaka S, Morikawa Y, Shimizu K, Hajikano H
Department of Pathology, National Children's Medical Research Center, Tokyo, Japan.
Virchows Arch A Pathol Anat Histopathol. 1988;412(4):307-14. doi: 10.1007/BF00750256.
Two cases of Ki-1 lymphomas in childhood were analyzed immunohistochemically and immunoelectron microscopically. They expressed Hodgkin's disease associated antigen, Ki-1, interleukin-2 receptor (IL2R), OKT9, and HLA-DR. Histologically, the tumour cells were large in size with abundant cytoplasm and atypical nuclei. Lymph node involvement was characterized by parafollicular and marginal sinus infiltration. These features were identical to those reported in Ki-1 lymphomas. Electron microscopically tumour cells had abundant cytoplasmic organelles with pleomorphic nuclei but had no specific granules. Some tumour cells had marked interdigitation of cell membrane. Immunoelectron microscopically Ki-1 was positive on cell membrane. Tumour cells had no T-cell or B-cell antigens except for Leu-3 (T4). Unexpectedly they expressed epithelial membrane antigen (EMA) strongly. EMA was positive on cell membrane and in the cytoplasm. EMA was detected effectively in paraffin-embedded sections. Among the malignant lymphomas in childhood tested, two cases were EMA-positive. The pattern of EMA-reactivity and the histology were very similar to Ki-1 lymphomas. These results strongly suggest that Ki-1 lymphomas in childhood may arise from non-lymphoid haematopoietic cells and that EMA can be used as a new marker to distinguish certain type of Ki-1 lymphomas in childhood.
对两例儿童期Ki-1淋巴瘤进行了免疫组织化学和免疫电子显微镜分析。它们表达霍奇金病相关抗原Ki-1、白细胞介素-2受体（IL2R）、OKT9和HLA-DR。组织学上，肿瘤细胞体积大，胞质丰富，核异型。淋巴结受累的特征为滤泡旁和边缘窦浸润。这些特征与报道的Ki-1淋巴瘤相同。电子显微镜下，肿瘤细胞有丰富的胞质细胞器，核多形性，但无特异性颗粒。一些肿瘤细胞有明显的细胞膜指状交叉。免疫电子显微镜下，Ki-1在细胞膜上呈阳性。除了Leu-3（T4）外，肿瘤细胞没有T细胞或B细胞抗原。出乎意料的是，它们强烈表达上皮膜抗原（EMA）。EMA在细胞膜和细胞质中呈阳性。在石蜡包埋切片中能有效检测到EMA。在检测的儿童期恶性淋巴瘤中，有两例EMA呈阳性。EMA反应模式和组织学与Ki-1淋巴瘤非常相似。这些结果强烈提示儿童期Ki-1淋巴瘤可能起源于非淋巴造血细胞，且EMA可作为区分儿童期某些类型Ki-1淋巴瘤的新标志物。
