Tamura K, Sawada H, Izumi Y, Fukuda T, Utsunomiya A, Ikeda S, Uike N, Tsukada J, Kawano F, Shibuya T, Gondo H, Okamura S, Suzumiya J
Department of Internal Medicine, Fukuoka University Hospital, Japan.
Eur J Haematol. 2001 Sep;67(3):152-7. doi: 10.1034/j.1600-0609.2001.5790514.x.
Chronic lymphocytic leukemia (CLL) is a rare disease in Japan. Recent advances in molecular biology, diagnostic criteria and classification of CLL have reinforced the concept of each category of CLL as a distinct entity. Since there have been no recent studies on the incidence and prevalence of CLL in Japan, the Kyushu Hematology Organization for Treatment (K-HOT) Study Group conducted two studies of CLL. One study is a prospective registration of newly diagnosed hematological disorders, which gave us some idea of the incidence of CLL in our region (Kyushu island) where adult T-cell leukemia is endemic. A total of 677 patients with hematological disorders were registered over a 6-month period and 11 patients were diagnosed as having CLL among 182 leukemia patients. This amounts to 6% of all leukemias, which is twice as frequent as previously reported in Japan. The other study is a retrospective analysis of CLL. Eleven institutions of the K-HOT Group analysed their diagnostic records of chronic lymphoid leukemia, and 145 patients with CLL were found over a period of 3-12 yr. After the data were reviewed 11 patients were excluded through having a different type of leukemia. The proportion of chronic B-cell lymphoid leukemia was 73% (98/134), while that of T-cell leukemia was 18% (24/134). The proportion of T-cell chronic leukemia was 5-6 times higher than that in Western countries. Two institutions had a complete database on hematological disorders. From this database, the annual incidence of CLL was estimated to be 0.48 per 100 000. Thus, the incidence of CLL in Japan is at least 4-5 times lower than that in Western countries, suggesting that chronic B-cell leukemia is really rare, but chronic leukemia of T-cell lineage develops in Japan as frequently as in Western societies. Further investigation is required to delineate why the incidence of B-CLL is so low in Japan.
慢性淋巴细胞白血病（CLL）在日本是一种罕见疾病。分子生物学、CLL诊断标准及分类方面的最新进展强化了将CLL各类型视为不同实体的概念。由于近期日本尚无关于CLL发病率和患病率的研究，九州血液治疗组织（K-HOT）研究小组开展了两项CLL研究。一项研究是对新诊断血液系统疾病的前瞻性登记，这让我们对本地区（九州岛，成人T细胞白血病为地方病）CLL的发病率有了一定了解。在6个月期间共登记了677例血液系统疾病患者，182例白血病患者中有11例被诊断为CLL。这占所有白血病的6%，是日本此前报道频率的两倍。另一项研究是对CLL的回顾性分析。K-HOT小组的11个机构分析了其慢性淋巴细胞白血病的诊断记录，在3至12年期间发现了145例CLL患者。数据审核后，11例因患有其他类型白血病而被排除。慢性B细胞淋巴细胞白血病的比例为73%（98/134），而T细胞白血病的比例为18%（24/134）。T细胞慢性白血病的比例比西方国家高5至6倍。两个机构有完整的血液系统疾病数据库。根据该数据库，CLL的年发病率估计为每10万人0.48例。因此，日本CLL的发病率至少比西方国家低4至5倍，这表明慢性B细胞白血病在日本确实罕见，但T细胞系慢性白血病在日本的发病频率与西方社会相同。需要进一步研究以阐明日本B-CLL发病率如此之低的原因。
