非霍奇金淋巴瘤NHL综述

　　Seminar

　　Non-Hodgkin lymphoma

　　James O Armitage, Randy D Gascoyne, Matthew A Lunning, Franco Cavalli

　　Lymphomas can a? ect any organ in the body, present with a wide range of symptoms, and be seen by primary care physicians and physicians from most specialties. They are traditionally divided into Hodgkin’s lymphoma (which accounts for about 10% of all lymphomas) and non-Hodgkin lymphoma, which is the topic of this Seminar. Non-Hodgkin lymphoma represents a wide spectrum of illnesses that vary from the most indolent to the most aggressive malignancies. They arise from lymphocytes that are at various stages of development, and the characteristics of the speci? c lymphoma subtype re? ect those of the cell from which they originated. Since this topic was last reviewed in The Lancet in 2012, advances in understanding the biology and genetics of non-Hodgkin lymphoma and the availability of new diagnostic methods and therapies have improved our ability to manage patients with this disorder.

　　Published OnlineJanuary 30, 2017

　　http://www.wendangwang.com/10.1016/S0140-6736(16)32407-2

　　Epidemiology and risk factors

　　Since the last review of non-Hodgkin lymphoma in The Lancet in 2012,1 advances in understanding the biology and genetics and the availability of new diagnostic methods and therapies have improved. An estimated 72 580 new cases of non-Hodgkin lymphoma are expected in the USA in 2016, and 13 413 new cases were reported in the UK in 2013.2,3 The relative frequency of speci? c subtypes of non-Hodgkin lymphoma varies geographically. The International Non-Hodgkin Lymphoma Classi? cation

　　4

　　Project studied 4539 cases from seven geographical regions (North America, western Europe, southeastern Europe, Central and South America, north Africa and Middle East, southern Africa, and the east Asia). Non-Hodgkin lymphomas were more likely to be B-cell lymphomas, and there was a higher incidence of low-grade B-cell lymphomas in high-income regions than in low-income and middle-income regions. By contrast, low-income and middle-income regions had a higher incidence of high-grade B-cell lymphomas and T-cell and natural killer (NK)-cell lymphomas than did high-income regions. Nasal-type extranodal NK–T-cell lymphoma was much more common in the east Asia—and, to a lesser degree, in Central and South America—than in other regions. Extranodal NK–T-cell lymphoma is strongly associated with Epstein-Barr virus infection, but the striking geographical variability in the incidence of this subtype of lymphoma indicates a contribution of host susceptibility. However, one study5 found that the distribution of lymphoma subtypes in Japan was changing and becoming more like the distribution found in the USA (ie, it was becoming westernised), suggesting that changes in lifestyle can alter these patterns.

　　Trends in the incidence of non-Hodgkin lymphoma have not been consistent. The incidence of non-Hodgkin lymphoma in Europe and North America increased in the 1990s and then stablised.6,7 However, looking at overall trends of incidence might not re? ect changes in the incidence of speci? c subtypes. For example, a study8 from the Netherlands that focused on the period from 1989 to 2007 showed that the incidence of indolent B-cell lymphomas, and T-cell and NK-cell non-Hodgkin lymphomas, rose considerably whereas the incidence of aggressive B-cell lymphomas remained stable.

　　occupational factors.9–11 Obesity has been found to be a Correspondence to: risk factor for di? use large B-cell lymphoma (DLBCL).12 Prof James O Armitage,

　　Genome-wide association studies have found loci that University of Nebraska Medical are associated with excessive risk for follicular lymphoma, Center, Nebraska Medical Center,

　　Omaha, NE 68198-7680, USA

　　marginal zone lymphoma, and DLBCL.13,14 joarmita@unmc.eduThe e? ects of some key risk factors such as hair dyes seem to be decreasing owing to changes in the ingredients used in these products.15 The risk of non-Hodgkin lymphoma in patients with autoimmune diseases—including rheumatoid arthritis, Sjgren syndrome, and systemic lupus erythematosus—has continued to increase.16 Whether this increased risk is related only to the autoimmune disease or to the immunosuppressive therapies used in its management is not clear. Patients who are immunosuppressed for other reasons, such as patients undergoing organ transplantation or those with HIV infection, are known to be at an increased risk of developing non-Hodgkin lymphoma.17

　　Both viral and bacterial infections have been closely associated with the development of non-Hodgkin lymphomas. Helicobacter pylori causes most gastric mucosa-associated lymphoid tissue (MALT) lymphomas.18 The Epstein-Barr virus is closely associated with both Burkitt lymphoma and nasal NK–T-cell lymphoma.19,20 Hepatitis C virus has been associated with splenic marginal zone lymphoma and DLBCL.21 Borrelia burgdorferi and Chlamydia psittacosis are thought to be

　　Search strategy and selection criteria

　　We searched PubMed and MEDLINE for articles published in English between Jan 1, 2012, and April 1, 2016, using the terms “non-Hodgkin lymphoma”, “di? use large B-cell

　　lymphoma”, “follicular lymphoma”, “mantle cell lymphoma”, “marginal zone lymphoma”, “Burkitt lymphoma”, “T-cell lymphoma” and “peripheral T-cell lymphoma”. In some cases, these manuscripts provided further references that were not included in the original search results but were included in this manuscript.

　　University of Nebraska Medical Center, Omaha, NE, USA (Prof J O Armitage MD, M A Lunning DO); British Columbia Cancer Agency and British Columbia Cancer Research Centre, Vancouver,

　　Factors a? ecting an individual’s risk of developing non-BC, Canada

　　Hodgkin lymphoma have been extensively studied. (Prof R D Gascoyne MD); and These factors include immune disorders, medicines, Oncology Institute of Southern

　　Switzerland, Bellinzona,

　　infections, lifestyle, genetics, race, family history, and Switzerland (Prof F Cavalli MD)

　　http://www.wendangwang.com Published online January 30, 2017 http://www.wendangwang.com/10.1016/S0140-6736(16)32407-2 1