Agbay Rose Lou Marie C, Medeiros L Jeffrey, Khoury Joseph D, Salem Alireza, Bueso-Ramos Carlos E, Loghavi Sanam
Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
Hum Pathol. 2017 Oct;68:7-21. doi: 10.1016/j.humpath.2017.03.024. Epub 2017 Apr 17.
Reactive germinal centers (GCs) in the bone marrow (BM) have been described in patients with autoimmune disorders, infections, malignancies, and following certain drug therapies, or as an isolated finding without obvious underlying disease. In this study, we describe the clinical conditions in which reactive GCs occur in BM samples, and their topography and accompanying laboratory and ancillary findings in the setting of a cancer center. We identified 32 BM specimens with reactive GCs with an estimated frequency less than 0.02% over a 12-year period. Fifteen (46.9%) BM specimens had concurrent hematolymphoid neoplasms: most often a variety of small B-cell lymphomas, but also myelodysplastic syndromes. One (3.1%) case was involved by metastatic melanoma. Isolated reactive GCs were observed in 16 (50%) patients. Most BM specimens (n = 25; 78.1%) showed only one reactive GC with a size ranging from 20 to 500 μm, and most GCs (29/32) were nonparatrabecular. GCs were positive for CD10 and BCL6, and were negative for BCL2. CD3 and CD5 demonstrated T cells surrounding the GC and CD21, and CD23 highlighted follicular dendritic cells. Reactive GCs are uncommon and can be seen in association with hematolymphoid and other types of neoplasms or as an isolated finding. Reactive GCs are usually located in a nonparatrabecular distribution. A panel of immunohistochemical stains is useful to confirm the nonneoplastic nature of these GCs to avoid misdiagnosis as lymphoma or as histologic evidence of transformation in a patient with small B-cell lymphoma in the bone marrow.
骨髓（BM）中的反应性生发中心（GCs）已在自身免疫性疾病、感染、恶性肿瘤患者以及接受某些药物治疗后被描述过，或者作为一种无明显潜在疾病的孤立发现。在本研究中，我们描述了BM样本中出现反应性GCs的临床情况、它们的形态以及在癌症中心背景下伴随的实验室和辅助检查结果。我们在12年期间识别出32个有反应性GCs的BM标本，估计频率低于0.02%。15个（46.9%）BM标本同时存在血液淋巴系统肿瘤：最常见的是各种小B细胞淋巴瘤，但也有骨髓增生异常综合征。1例（3.1%）为转移性黑色素瘤累及。16例（50%）患者观察到孤立的反应性GCs。大多数BM标本（n = 25；78.1%）仅显示一个反应性GC，大小范围为20至500μm，并且大多数GCs（29/32）位于非小梁旁。GCs对CD10和BCL6呈阳性，对BCL2呈阴性。CD3和CD5显示GC周围有T细胞，CD21和CD23突出显示滤泡树突状细胞。反应性GCs并不常见，可与血液淋巴系统及其他类型肿瘤相关出现或作为孤立发现。反应性GCs通常位于非小梁旁分布。一组免疫组织化学染色有助于确认这些GCs的非肿瘤性质，以避免误诊为淋巴瘤或作为骨髓中小B细胞淋巴瘤患者转化的组织学证据。
