title: Distribution of lymphoid neoplasms in the Republic of Korea: analysis of 5318 cases according to the World Health Organization classification.
abstract: Compared with the West, the overall incidence of lymphoid neoplasms is lower, and the subtype distribution is distinct in Asia. To comprehensively investigate the subtype distribution with the age and sex factors, and temporal changes of subtype proportions, we re-assessed all patients with lymphoid neoplasms diagnosed at a large oncology service in the Republic of Korea from 1989 to 2008 using the World Health Organization classifications. Of the total 5,318 patients, 66.9% had mature B-cell neoplasms, 12.5% had mature T/natural killer (NK)-cell neoplasms, 16.4% had precursor lymphoblastic leukemia/lymphoma (ALL/LBL), and 4.1% had Hodgkin's lymphoma. The most common subtypes were diffuse large B-cell lymphoma (30.5%), plasma cell myeloma (14.0%), extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue type (MALT lymphoma; 12.4%), B-cell ALL/LBL (11.3%), Hodgkin's lymphoma (4.1%), peripheral T-cell lymphoma unspecified (4.0%), T-cell ALL/LBL (3.9%), and extranodal NK/T-cell lymphoma of nasal type (3.9%). Most subtypes showed male predominance, with an average M/F ratio of 1.3. Most mature lymphoid neoplasms were diseases of adults (mean age, 53.5 yr), whereas ALL/LBLs were of young individuals (mean age, 20.3 yr). When the relative proportion of subtypes were compared between two decades (1989-1998 vs. 1999-2008), especially MALT lymphoma has increased in proportion, whereas T/NK-cell neoplasms and ALL/LBL have slightly decreased. In summary, the lymphoid neoplasms of Koreans shared some epidemiologic features similar to those of other countries, whereas some subtypes showed distinct features. Although the increase in incidence of lymphoid neoplasms is relatively modest in Korea, recent increase of MALT lymphoma and decrease of T/NK-cell neoplasms and ALL/LBL are interesting findings.
authors.affiliation: Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, 388-1 Poongnap-Dong, Seoul, South Korea.
authors.forename: Sun Och
authors.initials: SO
authors.lastname: Yoon
authors.forename: Cheolwon
authors.initials: C
authors.lastname: Suh
authors.forename: Dae Ho
authors.initials: DH
authors.lastname: Lee
authors.forename: Hyun-Sook
authors.initials: HS
authors.lastname: Chi
authors.forename: Chan Jeoung
authors.initials: CJ
authors.lastname: Park
authors.forename: Seong-Soo
authors.initials: SS
authors.lastname: Jang
authors.forename: Hai-Rim
authors.initials: HR
authors.lastname: Shin
authors.forename: Bong-Hee
authors.initials: BH
authors.lastname: Park
authors.forename: Jooryung
authors.initials: J
authors.lastname: Huh
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006689:Hodgkin Disease / Q000453:epidemiology / Q000473:pathology; D006801:Humans; D016130:Immunophenotyping; D015994:Incidence; D008223:Lymphoma / Q000145:classification / Q000453:epidemiology* / Q000473:pathology; D016393:Lymphoma, B-Cell / Q000453:epidemiology / Q000473:pathology; D018442:Lymphoma, B-Cell, Marginal Zone / Q000453:epidemiology / Q000473:pathology; D016399:Lymphoma, T-Cell / Q000453:epidemiology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000453:epidemiology / Q000473:pathology; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D014944:World Health Organization; D055815:Young Adult