Department of Pathology, Cancer Institute, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, 1419733141, Tehran, Iran.
Department of Pathology, Shariati Hospital, Tehran University of Medical Sciences, 1411713135, Tehran, Iran.
Ann Diagn Pathol. 2022 Oct;60:151974. doi: 10.1016/j.anndiagpath.2022.151974. Epub 2022 May 7.
Hodgkin's lymphoma (HL) is among the most prevalent lymphomas worldwide. PAX5 has a great value in separating this entity from other T cell lymphoma; however, it is weakly expressed in neoplastic cells. Polyclonal PAX8 was positive in a variety of lymphoid neoplasms in several previous studies and the staining paralleled that of PAX5 but monoclonal PAX8 was negative in the same neoplasms. The aim of this study was to compare immunohistochemical patterns of monoclonal PAX8 with PAX5 in Classical and NLPHL samples.
This retrospective study was conducted on 89 formalin-fixed paraffin embedded blocks from HL patients (69 Classical and 20 NLPHL) admitted to Imam Khomeini and Dr. Shariati hospitals, Tehran, Iran during 2016-2020. Diagnoses were confirmed by reviewing previous immunohistochemistry (IHC) studies, including PAX5. All samples were stained for PAX8 (clone MRQ-50). Expression intensity scoring was made for both antibodies in neoplastic and background cells based on nuclear staining percentage.
PAX8 was positive in neoplastic and background B lymphocytes of all classical and NLPHL samples. PAX8 Expression intensity was significantly higher in neoplastic and background cells compared to PAX5 in classical HL samples (P = 0.001). PAX5 expression intensity in neoplastic cells was significantly higher in NLPHL samples compared to classical HL (P = 0.040); however, no significant difference in PAX8 expression between neoplastic cells of NLPHL and HL was seen. PAX8 expression intensity was not significantly correlated with gender, histologic subtype, tumor location, and relapse.
PAX8 monoclonal antibody (clone MRQ-50) showed strong nuclear reactivity in neoplastic and background cells of classical HL and NLPHL samples. Therefore, this marker can be utilized as a valuable alternative for PAX5 in differentiating HL from other T cell lymphoma in challenging cases.
霍奇金淋巴瘤（HL）是全球最常见的淋巴瘤之一。PAX5 在将该实体与其他 T 细胞淋巴瘤区分开来方面具有重要价值；然而，它在肿瘤细胞中的表达较弱。在几项先前的研究中，多克隆 PAX8 在多种淋巴肿瘤中呈阳性，并且染色与 PAX5 平行，但同一种肿瘤中的单克隆 PAX8 呈阴性。本研究旨在比较经典型和 NLPHL 样本中单克隆 PAX8 与 PAX5 的免疫组化模式。
这项回顾性研究是在 2016 年至 2020 年期间，在伊朗德黑兰伊玛目霍梅尼和沙里亚特医院就诊的 89 例霍奇金淋巴瘤患者（69 例经典型和 20 例 NLPHL）的福尔马林固定石蜡包埋块上进行的。通过回顾之前的免疫组化（IHC）研究，包括 PAX5，来确认诊断。所有样本均染色用于 PAX8（克隆 MRQ-50）。根据核染色百分比，对两种抗体在肿瘤和背景细胞中的表达强度进行评分。
PAX8 在所有经典型和 NLPHL 样本的肿瘤和背景 B 淋巴细胞中均呈阳性。在经典 HL 样本中，PAX8 的表达强度在肿瘤和背景细胞中明显高于 PAX5（P=0.001）。在 NLPHL 样本中，PAX5 在肿瘤细胞中的表达强度明显高于经典 HL（P=0.040）；然而，在 NLPHL 和 HL 的肿瘤细胞中，PAX8 的表达强度没有明显差异。PAX8 表达强度与性别、组织学亚型、肿瘤位置和复发无显著相关性。
PAX8 单克隆抗体（克隆 MRQ-50）在经典 HL 和 NLPHL 样本的肿瘤和背景细胞中显示出强烈的核反应性。因此，该标志物可作为 PAX5 的有价值替代品，用于在具有挑战性的病例中区分 HL 与其他 T 细胞淋巴瘤。
