title: Trends in HTLV-1 prevalence and incidence of adult T-cell leukemia/lymphoma in Nagasaki, Japan.
abstract: Most previous studies aimed at estimating the number of human T-cell leukemia virus type-1 (HTLV-1) carriers in endemic areas have been based on seroprevalence rates in blood donors; however, this may result in underestimation because of the healthy donor effect. People who have health problem do not donate blood. In the present study, the number of HTLV-1 carriers in Nagasaki City was estimated based on the seroprevalence rates in a hospital-based population from Nagasaki University Hospital. In accordance with previous reports, seroprevalence of HTLV-1 was higher in females, and year of birth-specific seroprevalence showed a significant annual decline in both genders (P for trend: <0.0001). The estimated number of HTLV-1 carriers in Nagasaki City was 36,983. The incidence of adult T-cell leukemia/lymphoma (ATLL) among HTLV-1 carriers was estimated using data from the Nagasaki Prefectural Cancer Registry. The estimated annual incidence of ATLL was 61 per 100,000 HTLV-1 carriers, and the crude lifetime risk of the development was 7.29% for males and 3.78% for females. There is a large pool of HTLV-1 carriers aged over 70 years, and a continuing development of cases of ATLL among the elderly is therefore expected.
authors.affiliation: Department of Laboratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Koga
authors.forename: Masako
authors.initials: M
authors.lastname: Iwanaga
authors.forename: Midori
authors.initials: M
authors.lastname: Soda
authors.forename: Naoko
authors.initials: N
authors.lastname: Inokuchi
authors.forename: Daisuke
authors.initials: D
authors.lastname: Sasaki
authors.forename: Hiroo
authors.initials: H
authors.lastname: Hasegawa
authors.forename: Katsunori
authors.initials: K
authors.lastname: Yanagihara
authors.forename: Kazunari
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Shimeru
authors.initials: S
authors.lastname: Kamihira
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Yamada
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002353:Carrier State / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D015490:HTLV-I Infections / Q000150:complications* / Q000453:epidemiology*; D006761:Hospitals; D015368:Human T-lymphotropic virus 1 / Q000302:isolation & purification*; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007564:Japan; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000453:epidemiology* / Q000821:virology*; D008297:Male; D008875:Middle Aged; D016036:Seroepidemiologic Studies; D055815:Young Adult