Department of Diagnostic Pathology, National Cancer Center Hospital, Tokyo, Japan.
J Clin Exp Hematop. 2023;63(1):12-18. doi: 10.3960/jslrt.22046.
Outcomes of patients with histologic transformation (HT) of follicular lymphoma (FL) have been believed to be poor. The most common histologic subtype of transformation from FL is diffuse large B-cell lymphoma (DLBCL), which accounts for 90% of the cases, and the remaining 10% of the cases include classic Hodgkin lymphoma, high-grade B-cell lymphoma, plasmablastic lymphoma, B-acute lymphoblastic leukemia/lymphoma, histiocytic/dendritic cell sarcoma, and anaplastic large cell lymphoma-like lymphoma. Because the histologic criteria for the diagnosis of DLBCL transformed from FL are unclear, convenient histopathological criteria for HT are required. One of the proposed criteria of HT from our institute is the presence of diffuse architecture with a proportion of large lymphoma cells of ≥20%, and for challenging cases, Ki-67 index ≥50% is used as a reference. Patients with HT to non-DLBCL have poorer outcomes than those with HT to DLBCL; thus, rapid and accurate histologic diagnosis is desired. In this review, we discussed the recent literatures describing the histopathologic variety and proposal of definition of HT.
滤泡性淋巴瘤（FL）发生组织学转化（HT）患者的预后一直被认为较差。FL 最常见的转化组织学亚型为弥漫性大 B 细胞淋巴瘤（DLBCL），占 90%，其余 10%包括经典霍奇金淋巴瘤、高级别 B 细胞淋巴瘤、浆母细胞淋巴瘤、B 急性淋巴细胞白血病/淋巴瘤、组织细胞/树突状细胞肉瘤和间变性大细胞淋巴瘤样淋巴瘤。由于 FL 转化而来的 DLBCL 的组织学诊断标准尚不明确，因此需要明确用于 HT 的便捷组织病理学标准。我们研究所提出的 HT 标准之一是存在弥漫性结构，大淋巴瘤细胞比例≥20%，对于有挑战性的病例，Ki-67 指数≥50%可作为参考。发生 HT 至非 DLBCL 的患者比发生 HT 至 DLBCL 的患者预后更差，因此需要快速准确的组织学诊断。在这篇综述中，我们讨论了描述 HT 的组织病理学多样性和定义的最新文献。
