脾肿大可归因于红髓索和髓窦的弥漫性浸润伴髓索萎缩,这可能会导致脾脏内部健康血细胞的隔离、边缘化和破坏。 HCL的骨髓衰竭和脾脏肿大导致全血细胞减少。 骨髓中毛细胞的聚集和网状纤维化以及细胞因子产生失调的不良作用引起骨髓衰竭。[9]Cawley JC. The pathophysiology of the hairy cell. Hematol Oncol Clin North Am. 2006 Oct;20(5):1011-21.http://www.ncbi.nlm.nih.gov/pubmed/16990104?tool=bestpractice.com[10]Burthem J, Cawley JC. The bone marrow fibrosis of hairy-cell leukemia is caused by the synthesis and assembly of a fibronectin matrix by the hairy cells. Blood. 1994 Jan 15;83(2):497-504.http://bloodjournal.hematologylibrary.org/cgi/reprint/83/2/497http://www.ncbi.nlm.nih.gov/pubmed/8286747?tool=bestpractice.com
毛细胞是克隆性晚期B细胞,表达一系列B细胞标志。[11]Basso K, Liso A, Tiacci E, et al. Gene expression profiling of hairy cell leukemia reveals a phenotype related to memory B cells with altered expression of chemokine and adhesion receptors. J Exp Med. 2004 Jan 5;199(1):59-68.http://jem.rupress.org/cgi/content/full/199/1/59http://www.ncbi.nlm.nih.gov/pubmed/14707115?tool=bestpractice.com HCL 是非霍奇金淋巴瘤的一种类型。除了浆细胞抗原 (PCA1) 和几种其他抗原(例如 FMC7、CD19、CD20、CD22、CD25、CD72、CD40L、CD11c 和 CD103),毛细胞还表达抗酒石酸酸性磷酸酶 (tartrate-resistant acid phosphatase, TRAP)。[9]Cawley JC. The pathophysiology of the hairy cell. Hematol Oncol Clin North Am. 2006 Oct;20(5):1011-21.http://www.ncbi.nlm.nih.gov/pubmed/16990104?tool=bestpractice.com[12]Yam LT, Li CY, Lam KW. Tartrate-resistant acid phosphatase isoenzyme in the reticulum cells of leukemic reticuloendotheliosis. N Engl J Med. 1971 Feb 18;284(7):357-60.http://www.ncbi.nlm.nih.gov/pubmed/5275977?tool=bestpractice.com
HCL的典型免疫表型包括:[1]Foucar K, Falini B, Catovsky D, et al. Hairy cell leukemia. In: WHO classification of tumours of haematopoietic and lymphoid tissues, vol 2, 4th ed. Geneva, Switzerland: World Health Organization Press; 2008:188-90.
膜联蛋白 A1 是鉴别诊断的最特异性的标志物,因为没有其他的 B 细胞淋巴瘤能够进行表达。[1]Foucar K, Falini B, Catovsky D, et al. Hairy cell leukemia. In: WHO classification of tumours of haematopoietic and lymphoid tissues, vol 2, 4th ed. Geneva, Switzerland: World Health Organization Press; 2008:188-90. 但是,膜联蛋白 A1 对检测微小残留疾病没有帮助[13]Jones G, Parry-Jones N, Wilkins B, et al. Revised guidelines for the diagnosis and management of hairy cell leukaemia and hairy cell leukaemia variant*. Br J Haematol. 2012 Jan;156(2):186-95.http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2141.2011.08931.x/fullhttp://www.ncbi.nlm.nih.gov/pubmed/22111844?tool=bestpractice.com
HCL不表达CD21,一种不成熟B细胞的标志。
有研究表明,大量孤立性细胞遗传学异常与 HCL 有关,但没有特定的细胞遗传异常是该疾病的特异性病征。 几项研究报道HCL的染色体和基因异常可能包括+5、+12、5q13-或p53突变。[14]Forconi F, Sahota SS, Raspadori D, et al. Hairy cell leukemia: at the crossroad of somatic mutation and isotype switch. Blood. 2004 Nov 15;104(10):3312-7.http://bloodjournal.hematologylibrary.org/cgi/content/full/104/10/3312http://www.ncbi.nlm.nih.gov/pubmed/15284115?tool=bestpractice.com[15]Konig EA, Kusser WC, Day C, et al. p53 mutations in hairy cell leukemia. Leukemia. 2000 Apr;14(4):706-11.http://www.ncbi.nlm.nih.gov/pubmed/10764158?tool=bestpractice.com[16]Zuzel M, Cawley JC. The biology of hairy cells. Best Pract Res Clin Haematol. 2003 Mar;16(1):1-13.http://www.ncbi.nlm.nih.gov/pubmed/12670461?tool=bestpractice.com 一项研究结果显示,几乎所有典型 HCL 患者都存在 BRAF V600E 突变。[4]Tiacci E, Trifonov V, Schiavoni G, et al. BRAF mutations in hairy-cell leukemia. N Engl J Med. 2011 Jun 16;364(24):2305-15.http://www.nejm.org/doi/full/10.1056/NEJMoa1014209#t=articlehttp://www.ncbi.nlm.nih.gov/pubmed/21663470?tool=bestpractice.com