Bone Marrow Histopathological Changes in Neoplastic and Non-Neoplastic Diseases

自身免疫性淋巴细胞增生性综合征是一种罕见的遗传性疾病，其特征是fas介导的细胞凋亡缺陷、自身免疫性疾病、成熟T细胞受体α / β阳性、CD4和CD8双阴性T细胞的积累以及淋巴瘤的风险增加。尽管经常出现血液学异常，但关于自身免疫性淋巴细胞增生性综合征骨髓病理的文献很少。为了研究这些患者的骨髓发现，我们回顾性地回顾了来自240例种系FAS突变患者的31例骨髓活检。所有的活组织检查都是为了评估细胞减少或排除淋巴瘤。收集临床资料，进行形态学、免疫组织化学、流式细胞术和分子分析。骨髓淋巴细胞增多是主要特征，74%（23/31）的活检存在。淋巴样细胞表现出几种不同的浸润模式，最常见的是形成聚集体，包括15例T细胞，1例B细胞，另外7例T细胞和B细胞的混合物。少数病例免疫组化检测到双阴性T细胞（10/31;32%）；值得注意的是，除一例外，所有病例均有明显的双阴性t淋巴细胞聚集，其中4例弥漫性地取代了骨髓间隙。1例表现为Rosai-Dorfman病的特征，S-100+细胞分散，并伴有淋巴细胞增多和双阴性T细胞。在所有评估病例中，聚合酶链反应均未检测到克隆性B细胞或T细胞。经典霍奇金淋巴瘤确诊3例。我们的研究结果表明，T细胞的浸润，或很少B细胞，可以广泛的患者自身免疫性淋巴细胞增生性综合征，模拟淋巴瘤。综合临床、组织学、免疫组织化学以及其他辅助测试的多模式方法可以帮助避免这种诊断陷阱。

Autoimmune lymphoproliferative syndrome is a rare genetic disorder characterized by defective FAS-mediated apoptosis, autoimmune disease, accumulation of mature T-cell receptor alpha/beta positive, CD4 and CD8 double-negative T cells and increased risk of lymphoma. Despite frequent hematologic abnormalities, literature is scarce regarding the bone marrow pathology in autoimmune lymphoproliferative syndrome. To investigate bone marrow findings in these patients, we retrospectively reviewed 31 bone marrow biopsies from a cohort of 240 patients with germline FAS mutations. All biopsies were performed for the evaluation of cytopenias or to rule out lymphoma. Clinical information was collected and morphological, immunohistochemical, flow cytometric and molecular studies were performed. Bone marrow lymphocytosis was the predominant feature, present in 74% (23/31) of biopsies. The lymphoid cells showed several different patterns of infiltration, most often forming aggregates comprising T cells in 15 cases, B cells in one and a mixture of T and B cells in the other seven cases. Double-negative T cells were detected by immunohistochemistry in the minority of cases (10/31; 32%); significantly, all but one of these cases had prominent double-negative T-lymphoid aggregates, which in four cases diffusely replaced the marrow space. One case showed features of Rosai-Dorfman disease, containing scattered S-100+ cells with emperipolesis and double-negative T cells. No clonal B or T cells were detected by polymerase chain reaction in any evaluated cases. Classical Hodgkin lymphoma was identified in three cases. Our results demonstrate that infiltrates of T cells, or rarely B cells, can be extensive in patients with autoimmune lymphoproliferative syndrome, mimicking lymphoma. A multi-modality approach, integrating clinical, histological, immunohistochemical as well as other ancillary tests, can help avoid this diagnostic pitfall. We investigated expression of the B-cell maturation antigen (BCMA) in cases of multiple myeloma in collaboration with Dr. Kochenderfer, NCI. Therapies with novel mechanisms of action are needed for patients with multiple myeloma. Dr. Kochenderfe conducted the first-in-humans clinical trial of chimeric antigen receptor (CAR) T cells targeting BCMA. T-cells expressing the CAR used in this work (CAR-BCMA) specifically recognized BCMA-expressing cells. Twelve patients received CAR-BCMA T cells in this dose-escalation trial. Among the 6 patients treated on the lowest 2 dose levels, limited anti-myeloma activity and mild toxicity occurred. On the third dose level, 1 patient obtained a very good partial remission. Two patients were treated on the fourth dose level of 9 10(6) CAR(+) T cells/kg body weight. Before treatment, the first patient on the fourth dose level had chemotherapy-resistant multiple myeloma, making up 90% of bone marrow cells. After treatment, bone marrow plasma cells became undetectable by flow cytometry, and the patient's myeloma entered a stringent complete remission that lasted for 17 weeks before relapse. The second patient on the fourth dose level had chemotherapy-resistant myeloma making up 80% of bone marrow cells before treatment. Twenty-eight weeks after this patient received CAR-BCMA T cells, bone marrow plasma cells were undetectable by flow cytometry, and the serum monoclonal protein had decreased by >95%. This patient is in an ongoing very good partial remission. Both patients treated on the fourth dose level had toxicity consistent with cytokine-release syndrome including fever, hypotension, and dyspnea. Both patients had prolonged cytopenias. These findings demonstrated for the first time anti-myeloma activity of CAR-BCMA T cells. Host-related immunodeficiency is known to play a role in the development of multiple myeloma (MM) from its precursor conditions (monoclonal gammopathy of undetermined significance, MGUS, smoldering multiple myeloma, SMM). In order to understand the underlying immune changes in this process, we characterized immune patterns from MGUS to SMM to MM. We further sought to identify potential novel immune biomarkers that may predict progression of SMM to MM. We characterized patterns of circulating lymphocytes in 181 patients using multiparametric flow cytometry. We found decreased B- (p=.0003), increased T- (p=.037) and unaltered NK cell proportions from MGUS to SMM to MM. To gain insights into functional variability, we further characterized immunophenotypic lymphocyte subsets, which uncovered differences in CD57 subsets. Specifically, we found that SMM patients who eventually progressed to MM showed decreased proportions of CD57-CD56+(p=.0061) and CD57-CD16+(p=.035) lymphocyte subsets. We thus report novel data characterizing the nature of host-related immunodeficiency in the development of MM. We show sequential changes in lymphocyte subsets from MGUS to SMM to MM. We further suggest that CD57 subsets may serve as potential markers of progression from SMM to MM. Our findings support the study of lymphocyte subsets in the search for immune biomarkers. Such markers could provide clinical guidance in managing myeloma precursor disease. Disease progression in patients with chronic lymphocytic leukemia (CLL) treated with ibrutinib has been attributed to histologic transformation or acquired mutations in BTK and PLCG2. The rate of resistance and clonal composition of progressed disease are incompletely characterized. In collaboration with Dr. Wiestner, NHLBI, we have reviewed histopathological findings in CLL patients treated with single-agent ibrutinib on an investigator-initiated phase 2 trial. With median follow-up of 34 months, 15 of 84 evaluable patients (17.9%) progressed. Relapsed/refractory disease at study entry, TP53 aberration, advanced Rai stage, and high -2 microglobulin were independently associated with inferior progression-free survival (P < .05 for all tests). Histologic transformation occurred in 5 patients (6.0%) and was limited to the first 15 months on ibrutinib. In contrast, progression due to CLL in 10 patients (11.9%) occurred later, diagnosed at a median 38 months on study. At progression, mutations in BTK (Cys481) and/or PLCG2 (within the autoinhibitory domain) were found in 9 patients (10.7%), in 8 of 10 patients with progressive CLL, and in 1 patient with prolymphocytic transformation. Applying high-sensitivity testing (detection limit 1 in 1000 cells) to stored samples, mutations were detected up to 15 months before manifestation of clinical progression (range, 2.9-15.4 months). In 5 patients (6.0%), multiple subclones carrying different mutations arose independently, leading to subclonal heterogeneity of resistant disease. For a seamless transition to alternative targeted agents, patients progressing with CLL were continued on ibrutinib for up to 3 months, with 19.8 months median survival from the time of progression.