虽然尝试给予口服叶酸和口服维生素 B6 是合理的,但对于无症状以及无高尿酸血症或需治疗性贫血的低危患者,无需进行治疗。在有症状的患者中,造血干细胞移植是唯一可能治愈的治疗选择。卢佐替尼、沙利度胺加泼尼松龙、低剂量干扰素、低剂量美法仑、羟基尿素(又名羟基脲)、脾切除或脾照射是其他治疗选择。
风险分层
目前有两套评分系统用于原发性骨髓纤维化患者的风险和预后分层:
国际预后评分系统 (IPSS),[17]Cervantes F, Dupriez B, Pereira A, et al. New prognostic scoring system for primary myelofibrosis based on a study of the International Working Group for Myelofibrosis Research and Treatment. Blood. 2009;113:2895-2901.http://bloodjournal.hematologylibrary.org/content/113/13/2895.full.pdf+htmlhttp://www.ncbi.nlm.nih.gov/pubmed/18988864?tool=bestpractice.com和
动态国际预后评分系统 (DIPSS)。[4]Passamonti F, Cervantes F, Vannucchi AM, et al. A dynamic prognostic model to predict survival in primary myelofibrosis: a study by the IWG-MRT (International Working Group for Myeloproliferative Neoplasms Research and Treatment). Blood. 2010;115:1703-1708.http://bloodjournal.hematologylibrary.org/cgi/content/full/115/9/1703http://www.ncbi.nlm.nih.gov/pubmed/20008785?tool=bestpractice.com
IPSS 和 DIPPS 的危险因素相同(年龄 65 岁以上、贫血、白细胞计数异常、循环中原始血细胞 > 1% 以及全身性症状)。然而,前者用于患者确诊时的预后评估,而 DIPSS 用于在确诊后的任何时间点进行的生存期评估。应当指出,这些分类系统并未反映钙网蛋白 (CALR) 或其他突变的影响,并且存在两种或更多突变会导致生存期缩短。[18]Tefferi A, Lasho TL, Finke CM, et al. CALR vs JAK2 vs MPL-mutated or triple-negative myelofibrosis: clinical, cytogenetic and molecular comparisons. Leukemia. 2014;28:1472-1477.http://www.ncbi.nlm.nih.gov/pubmed/24402162?tool=bestpractice.com[19]Tefferi A, Guglielmelli P, Larson DR, et al. Long-term survival and blast transformation in molecularly annotated essential thrombocythemia, polycythemia vera, and myelofibrosis. Blood. 2014;124:2507-2513.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4199952/http://www.ncbi.nlm.nih.gov/pubmed/25037629?tool=bestpractice.com[20]Rotunno G, Pacilli A, Artusi V, et al. Epidemiology and clinical relevance of mutations in post-polycythemia vera and post-essential thrombocythemia myelofibrosis. A study on 359 patients of the AGIMM group. Am J Hematol. 2016 Apr 2 [Epub ahead of print].http://www.ncbi.nlm.nih.gov/pubmed/27037840?tool=bestpractice.com[21]Rampal R, Ahn J, Abdel-Wahab O, et al. Genomic and functional analysis of leukemic transformation of myeloproliferative neoplasms. Proc Natl Acad Sci U S A. 2014;111:E5401-E5410.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4273376/http://www.ncbi.nlm.nih.gov/pubmed/25516983?tool=bestpractice.com[22]Guglielmelli P, Lasho TL, Rotunno G, et al. The number of prognostically detrimental mutations and prognosis in primary myelofibrosis: an international study of 797 patients. Leukemia. 2014;28:1804-1810.http://www.ncbi.nlm.nih.gov/pubmed/24549259?tool=bestpractice.com
无症状
虽然尝试给予口服叶酸和口服维生素 B6 是合理的,但对于无症状以及无高尿酸血症或需治疗性贫血的低危患者,无需进行治疗。对于高尿酸血症患者,可给予别嘌呤醇。对于无症状且血清尿酸水平正常的白细胞增多症患者或无症状的血小板增多症患者,无需进行治疗。在其中一些患者中,聚乙二醇干扰素已经成功用于减少骨髓纤维化和脾肿大,改善血液计数。
有症状的患者:≤65 岁并适合骨髓移植
对于原发性骨髓纤维化 (PMF),同种异体造血干细胞移植是唯一可能治愈的疗法。[23]Kroger N, Mesa RA. Choosing between stem cell therapy and drugs in myelofibrosis. Leukemia. 2008;22:474-486.http://www.ncbi.nlm.nih.gov/pubmed/18185525?tool=bestpractice.com[24]Stewart WA, Pearce R, Kirkland KE, et al; British Society for Blood and Marrow Transplantation. The role of allogeneic SCT in primary myelofibrosis: a British Society for Blood and Marrow Transplantation study. Bone Marrow Transplant. 2010;45:1587-1593.http://www.ncbi.nlm.nih.gov/pubmed/20154739?tool=bestpractice.com<50 岁并具有≥2 项不良特征(包括贫血 (Hb<100 g/L [<10 g/dL])、细胞遗传学异常或原始细胞 (>1%))的患者,在确诊后应尽快考虑清髓性骨髓移植。50 至 65 岁并具有≥2 项不良特征(包括贫血 (Hb<100 g/L [<10 g/dL])、细胞遗传学异常、原始细胞 (>1%) 或≥2 种基因突变)的患者,在确诊后应尽快考虑非清髓性(低强度)骨髓移植。[25]Kroger NM, Deeg JH, Olavarria E, et al. Indication and management of allogeneic stem cell transplantation in primary myelofibrosis: a consensus process by an EBMT/ELN international working group. Leukemia. 2015;29:2126-2133.http://www.ncbi.nlm.nih.gov/pubmed/26293647?tool=bestpractice.com
在有良好预后的患者中已取得了最好的结果。[26]Ballen KK, Shrestha S, Sobocinski KA, et al. Outcome of transplantation for myelofibrosis. Biol Blood Marrow Transplant. 2010;16:358-367.http://www.ncbi.nlm.nih.gov/pubmed/19879949?tool=bestpractice.com[27]Kroger N, Holler E, Kobbe G, et al. Allogeneic stem cell transplantation after reduced-intensity conditioning in patients with myelofibrosis: a prospective, multicenter study of the Chronic Leukemia Working Party of the European Group for Blood and Marrow Transplantation. Blood. 2009;114:5264-5270.http://bloodjournal.hematologylibrary.org/cgi/content/full/114/26/5264http://www.ncbi.nlm.nih.gov/pubmed/19812383?tool=bestpractice.com与移植相关的死亡率高达 32%,5 年生存率为 60%。现已发现低强度的预处理方案可以减少移植相关的死亡率并获得 > 70% 的缓解率,但这种方法是否能进一步降低移植相关的死亡率仍有待研究。需进行前瞻性研究,以确定最有效的预处理方案、移植的最佳时机以及哪些患者会从这种手术中受益最大。
有症状的患者:> 65 岁或者不适合骨髓移植
脾肿大是原发性骨髓纤维化最令人苦恼的并发症,会导致机械性不适、营养不足(重度虚弱和消瘦)、脾梗死、门静脉和肺动脉高压以及血细胞扣留。
在 PMF 患者中脾肿大非常常见,有很高的发病率。对 PMF 患者进行脾切除术是非常重大的手术,需谨慎考虑,特别是能够使用可有效降低脾脏体积的新药时。[28]Verstovsek S, Kantarjian H, Mesa RA, et al. Safety and efficacy of INCB018424, a JAK1 and JAK2 inhibitor, in myelofibrosis. N Engl J Med. 2010;363:1117-1127.http://www.nejm.org/doi/full/10.1056/NEJMoa1002028#t=articlehttp://www.ncbi.nlm.nih.gov/pubmed/20843246?tool=bestpractice.com[29]Tefferi A, Pardanani A. Serious adverse events during ruxolitinib treatment
discontinuation in patients with myelofibrosis. Mayo Clin Proc. 2011.86:1188-1191.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3228619/http://www.ncbi.nlm.nih.gov/pubmed/22034658?tool=bestpractice.com增大的脾脏及其血管、不可避免地存在黏连、PMF 患者的出血倾向以及通常欠佳的营养状况,使手术治疗脾肿大非常具有挑战性,而且经常是不可行的。[30]Mesa RA. How I treat symptomatic splenomegaly in patients with myelofibrosis. Blood. 2009;113:5394-5400.http://www.ncbi.nlm.nih.gov/pubmed/19332765?tool=bestpractice.com现在有一种美国食品药物管理局 (FDA) 批准的 JAK2 抑制剂 - 卢佐替尼 (ruxolitinib),用于具有中高风险的骨髓纤维化患者,可以有效缩小脾脏,并减轻全身症状。[31]Verstovsek S, Mesa RA, Gotlib J, et al. A double-blind, placebo-controlled trial of ruxolitinib for myelofibrosis. N Engl J Med. 2012;366:799-807.http://www.nejm.org/doi/full/10.1056/NEJMoa1110557#t=articlehttp://www.ncbi.nlm.nih.gov/pubmed/22375971?tool=bestpractice.com[32]Harrison C, Kiladjian JJ, Al-Ali HK, et al. JAK inhibition with ruxolitinib versus best available therapy for myelofibrosis. N Engl J Med. 2012;366:787-798.http://www.nejm.org/doi/full/10.1056/NEJMoa1110556#t=articlehttp://www.ncbi.nlm.nih.gov/pubmed/22375970?tool=bestpractice.com[33]Deisseroth A, Kaminskas E, Grillo J, et al. US Food and Drug Administration approval: ruxolitinib for the treatment of patients with intermediate and high-risk myelofibrosis. Clin Cancer Res. 2012;18:3212-3217.http://www.ncbi.nlm.nih.gov/pubmed/22544377?tool=bestpractice.com[34]Cervantes F, Vannucchi AM, Kiladjian JJ, et al.; COMFORT-II investigators. Three-year efficacy, safety, and survival findings from COMFORT-II, a phase 3 study comparing ruxolitinib with best available therapy for myelofibrosis. Blood. 2013;122:4047-4053.http://bloodjournal.hematologylibrary.org/content/122/25/4047.longhttp://www.ncbi.nlm.nih.gov/pubmed/24174625?tool=bestpractice.com[35]Harrison CN, Mesa RA, Kiladjian JJ, et al. Health-related quality of life and symptoms in patients with myelofibrosis treated with ruxolitinib versus best available therapy. Br J Haematol. 2013;162:229-239.http://www.ncbi.nlm.nih.gov/pubmed/23672349?tool=bestpractice.com[36]Verstovsek S, Mesa RA, Gotlib J, et al. Efficacy, safety and survival with ruxolitinib in
patients with myelofibrosis: results of a median 2-year follow-up of COMFORT-I.
Haematologica. 2013;98:1865-1871.http://www.haematologica.org/content/98/12/1865.longhttp://www.ncbi.nlm.nih.gov/pubmed/24038026?tool=bestpractice.com应始终考虑是否可以使用这种药物治疗来代替脾切除术。只要坚持用药,卢佐替尼的效果是持久的,但不宜突然停药。药物可用于血小板减少性 PMF 患者,但应从低剂量开始,并逐渐增加剂量。[37]Talpaz M, Paquette R, Afrin L, et al. Interim analysis of safety and efficacy of ruxolitinib in patients with myelofibrosis and low platelet counts. J Hematol Oncol. 2013;6:81.http://www.jhoonline.org/content/6/1/81http://www.ncbi.nlm.nih.gov/pubmed/24283202?tool=bestpractice.com如果将手术作为一项选择,应在术前评估门静脉高压的情况,如果必要,应给予肠外高营养支持,以避免术后并发症。氨基己酸可用于血小板减少性出血。虽然大多数患者对脾切除耐受良好,但随后的血小板增多症和肝髓外造血可能难以控制。
已经在特定患者中使用外束放射治疗以改善 PMF 脾肿大的症状,但中性粒细胞减少症和感染的发生率较高,因而不是一种持久的治疗。[38]Elliott MA, Chen MG, Silverstein MN, et al. Splenic irradiation for symptomatic splenomegaly associated with myelofibrosis with myeloid metaplasia. Br J Haematol. 1998;103:505-511.http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2141.1998.00998.x/fullhttp://www.ncbi.nlm.nih.gov/pubmed/9827926?tool=bestpractice.com[39]Bouabdallah R, Coso D, Gonzague-Casabianca L, et al. Safety and efficacy of splenic irradiation in the treatment of patients with idiopathic myelofibrosis: a report on 15 patients. Leuk Res. 2000;24:491-495.http://www.ncbi.nlm.nih.gov/pubmed/10781683?tool=bestpractice.com
低剂量沙利度胺和泼尼松龙已可成功减轻脾肿大,但血小板增多症是一个副作用。
采用降低强度预处理方法,可以使骨髓移植在≥65 岁的患者中安全开展。[25]Kroger NM, Deeg JH, Olavarria E, et al. Indication and management of allogeneic stem cell transplantation in primary myelofibrosis: a consensus process by an EBMT/ELN international working group. Leukemia. 2015;29:2126-2133.http://www.ncbi.nlm.nih.gov/pubmed/26293647?tool=bestpractice.com
血小板增多的非妊娠患者
目前,卢佐替尼是控制 PMF 患者器官肿大和血细胞计数的首选药物。[31]Verstovsek S, Mesa RA, Gotlib J, et al. A double-blind, placebo-controlled trial of ruxolitinib for myelofibrosis. N Engl J Med. 2012;366:799-807.http://www.nejm.org/doi/full/10.1056/NEJMoa1110557#t=articlehttp://www.ncbi.nlm.nih.gov/pubmed/22375971?tool=bestpractice.com[32]Harrison C, Kiladjian JJ, Al-Ali HK, et al. JAK inhibition with ruxolitinib versus best available therapy for myelofibrosis. N Engl J Med. 2012;366:787-798.http://www.nejm.org/doi/full/10.1056/NEJMoa1110556#t=articlehttp://www.ncbi.nlm.nih.gov/pubmed/22375970?tool=bestpractice.com[33]Deisseroth A, Kaminskas E, Grillo J, et al. US Food and Drug Administration approval: ruxolitinib for the treatment of patients with intermediate and high-risk myelofibrosis. Clin Cancer Res. 2012;18:3212-3217.http://www.ncbi.nlm.nih.gov/pubmed/22544377?tool=bestpractice.com已证实羟基脲有致畸性并可能导致白血病,除非证明卢佐替尼无效,否则不应再使用羟基脲。
无血小板增多的非妊娠患者
可以使用卢佐替尼、沙利度胺、干扰素、脾切除术或脾照射来缩小脾脏体积。[30]Mesa RA. How I treat symptomatic splenomegaly in patients with myelofibrosis. Blood. 2009;113:5394-5400.http://www.ncbi.nlm.nih.gov/pubmed/19332765?tool=bestpractice.com[40]Thomas DA, Giles FJ, Albitar M, et al. Thalidomide therapy for myelofibrosis with myeloid metaplasia. Cancer. 2006;106:1974-1984.http://onlinelibrary.wiley.com/doi/10.1002/cncr.21827/fullhttp://www.ncbi.nlm.nih.gov/pubmed/16583431?tool=bestpractice.com
卢佐替尼是初始治疗的首选方法。[31]Verstovsek S, Mesa RA, Gotlib J, et al. A double-blind, placebo-controlled trial of ruxolitinib for myelofibrosis. N Engl J Med. 2012;366:799-807.http://www.nejm.org/doi/full/10.1056/NEJMoa1110557#t=articlehttp://www.ncbi.nlm.nih.gov/pubmed/22375971?tool=bestpractice.com[32]Harrison C, Kiladjian JJ, Al-Ali HK, et al. JAK inhibition with ruxolitinib versus best available therapy for myelofibrosis. N Engl J Med. 2012;366:787-798.http://www.nejm.org/doi/full/10.1056/NEJMoa1110556#t=articlehttp://www.ncbi.nlm.nih.gov/pubmed/22375970?tool=bestpractice.com[33]Deisseroth A, Kaminskas E, Grillo J, et al. US Food and Drug Administration approval: ruxolitinib for the treatment of patients with intermediate and high-risk myelofibrosis. Clin Cancer Res. 2012;18:3212-3217.http://www.ncbi.nlm.nih.gov/pubmed/22544377?tool=bestpractice.com如果卢佐替尼无效,其他选择包括干扰素(如果血细胞计数合适),或沙利度胺加泼尼松龙。如果这些药物无效,可尝试非药物措施。脾切除术优于脾照射。脾照射可有效减轻脾脏疼痛,并暂时缩小脾脏体积。但其使用应严格限于不能手术的患者,因为如果在脾切除术前进行照射,会有无法预知的严重血细胞减少的风险,以及增加大出血的风险。
由于很可能导致白血病,故不建议将马法兰和白消安用于 PMF 的基础疗法,但它们可改善白细胞增多症,对脾肿大也有一定的改善作用。它们仅用于其他措施失败的病例,且应低剂量给药。
脾肿大的妊娠患者
干扰素治疗是首选疗法。由于具有诱导白细胞减少或血小板减少的作用,该药的使用可能受限,但它可缩小脾肿大。这在妊娠期尤其有用,因为此时禁止进行化疗和使用沙利度胺。建议给予低剂量干扰素。[41]Silver RT, Vandris K, Goldman JJ. Recombinant interferon-alpha may retard progression of early primary myelofibrosis: a preliminary report. Blood. 2011;117:6669-6672.http://bloodjournal.hematologylibrary.org/content/117/24/6669.longhttp://www.ncbi.nlm.nih.gov/pubmed/21518929?tool=bestpractice.com
辅助治疗
贫血患者
达那唑已被用于辅助治疗 PMF 贫血。目前还不清楚它的效果是血浆容量减少的结果,还是确实可以增加红细胞的数量。肝功能不全、液体潴留和前列腺增生等副作用限制了它的目标人群。达那唑禁止在妊娠期使用。
使用重组红细胞生成素(妊娠和非妊娠患者)进行辅助治疗可能对由内源性红细胞生成素水平过低 (< 125 mU/mL) 所导致的贫血有效。[42]Tsiara SN, Chaidos A, Bourantas LK, et al. Recombinant human erythropoietin for the treatment of anaemia in patients with chronic idiopathic myelofibrosis. Acta Haematol. 2007;117:156-161.http://www.ncbi.nlm.nih.gov/pubmed/17159338?tool=bestpractice.com激素会导致可逆性的脾肿大或肝肿大。对于具有低输血需求的患者可能最有效。
高尿酸血症患者
髓外造血患者