Yang Shenmiao, Gale Robert Peter, Shi Hongxia, Liu Yanrong, Lai Yueyun, Lu Jin, Huang Xiaojun
Peking University Peoples Hospital, Peking University Institute of Hematology, China.
Haematology Research Centre, Division of Experimental Medicine, Department of Medicine, Imperial College London, London, SW7 2AZ, UK.
Leuk Res. 2018 Oct;73:16-20. doi: 10.1016/j.leukres.2018.08.011. Epub 2018 Aug 22.
Chronic lymphocytic leukaemia (CLL) is 10- to 20-fold less common in Asians (including Han Chinese) compared with persons of predominately European descent. Why is unknown but seems predominately genetic. We observed an increasing frequency of new cases of CLL at our Haematology Centre beginning 2011 and wondered why.
Determine the cause(s) for this increased frequency.
We interrogated the context of CLL diagnosis in 483 consecutive subjects seen at the Institute of Haematology of a large referral hospital in Beijing. 3 cohorts were considered based on why a CBC was done to establish the CLL diagnosis: (1) a CBC-testing situation unrelated to a health condition such as a routine annual health exam or application for employment or medical insurance (termed routine CBC); (2) an unrelated medical condition such as a cold, influenza, heart disease etc. (termed CBC for other disorders); and (3) signs and/or symptoms consistent with CLL such as lymph-adenopathy, hepato- or splenomegaly, fatigue, B-symptoms etc. (termed CBC for possible CLL).
Data regarding context of CLL diagnosis were available for 389 subjects (81%). Proportions of subjects in the 3 cohorts were 44% (95% confidence interval [CI]; 39, 49%), 24% (20, 28%) and 32% (28, 37%). The proportion of subjects whose evaluation of CLL was prompted by an abnormal CBC not for possible CLL (cohorts 1 and 2) increased over the surveillance interval (r = 0.164; P = 0.001) as did median age at diagnosis (r = 0.207; P < 0.001). Age at diagnosis was correlated with probability of CLL being suspected because of an abnormal routine CBC (r = 0.249; P < 0.001); 42% (32, 53%) amongst subjects ≤50 years versus 86% (75, 92%; P < 0.001) among those >70 years. Consistent with this, older subjects were diagnosed at Rai stage-0 with asymptomatic disease compared with younger subjects (P < 0.001).
Our data suggest much of the increased frequency of CLL at our centre and likely elsewhere in China predominately reflects ascertainment bias. Other variables may also operate.
与主要为欧洲血统的人相比，慢性淋巴细胞白血病（CLL）在亚洲人（包括汉族）中的发病率低10至20倍。原因尚不清楚，但似乎主要是遗传因素。我们注意到自2011年起，我院血液科新诊断的CLL病例数不断增加，对此感到疑惑。
确定病例数增加的原因。
我们调查了北京一家大型转诊医院血液研究所连续收治的483例CLL患者的诊断背景。根据进行血常规检查以确诊CLL的原因，将患者分为3组：（1）与健康状况无关的血常规检查情况，如常规年度体检、求职或医疗保险申请（称为常规血常规）；（2）其他疾病，如感冒、流感、心脏病等（称为因其他疾病进行的血常规检查）；（3）有与CLL相符的体征和/或症状，如淋巴结肿大、肝脾肿大、疲劳、B症状等（称为因可能患有CLL进行的血常规检查）。
389例患者（81%）有CLL诊断背景的数据。3组患者的比例分别为44%（95%置信区间[CI]：39，49%）、24%（20，28%）和32%（28，37%）。在监测期内，因血常规异常（而非可能患有CLL）而促使进行CLL评估的患者比例（第1组和第2组）有所增加（r = 0.164；P = 0.001），诊断时的中位年龄也有所增加（r = 0.207；P < 0.001）。诊断时的年龄与因常规血常规异常而怀疑患有CLL的概率相关（r = 0.249；P < 0.001）；≤50岁的患者中这一比例为42%（32，53%），而>70岁的患者中这一比例为86%（75，92%；P < 0.001）。与此一致的是，与年轻患者相比，老年患者多在Rai 0期被诊断为无症状疾病（P < 0.001）。
我们的数据表明，我院CLL病例数增加，在中国其他地方可能也是如此，这主要反映了确诊偏倚。其他因素可能也有作用。
