Human T-cell leukemia virus type I (HTLV-1) proviral load and disease progression in asymptomatic HTLV-1 carriers: a nationwide prospective study in Japan.
Definitive risk factors for the development of adult T-cell leukemia (ATL) among asymptomatic human T-cell leukemia virus type I (HTLV-1) carriers remain unclear. Recently, HTLV-1 proviral loads have been evaluated as important predictors of ATL, but a few small prospective studies have been conducted. We prospectively evaluated 1218 asymptomatic HTLV-1 carriers (426 males and 792 females) who were enrolled during 2002 to 2008. The proviral load at enrollment was significantly higher in males than females (median, 2.10 vs 1.39 copies/100 peripheral blood mononuclear cells [PBMCs]; P < .001), in those 40 to 49 and 50 to 59 years of age than that of those 40 years of age and younger (P = .02 and .007, respectively), and in those with a family history of ATL than those without the history (median, 2.32 vs 1.33 copies/100 PBMCs; P = .005). During follow-up, 14 participants progressed to overt ATL. Their baseline proviral load was high (range, 4.17-28.58 copies/100 PBMCs). None developed ATL among those with a baseline proviral load lower than approximately 4 copies. Multivariate Cox analyses indicated that not only a higher proviral load, advanced age, family history of ATL, and first opportunity for HTLV-1 testing during treatment for other diseases were independent risk factors for progression of ATL.
Iwanaga
Masako
M
Department of Hematology and Molecular Medicine, Atomic Bomb Disease Institute, Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan. masakoiwng@gmail.com
Watanabe
Toshiki
T
Utsunomiya
Atae
A
Okayama
Akihiko
A
Uchimaru
Kaoru
K
Koh
Ki-Ryang
KR
Ogata
Masao
M
Kikuchi
Hiroshi
H
Sagara
Yasuko
Y
Uozumi
Kimiharu
K
Mochizuki
Manabu
M
Tsukasaki
Kunihiro
K
Saburi
Yoshio
Y
Yamamura
Masaomi
M
Tanaka
Junji
J
Moriuchi
Yukiyoshi
Y
Hino
Shigeo
S
Kamihira
Shimeru
S
Yamaguchi
Kazunari
K
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D015139:Blotting, Southern; D002353:Carrier State; D002648:Child; D004279:DNA, Viral / Q000235:genetics; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D015490:HTLV-I Infections / Q000097:blood / Q000453:epidemiology / Q000821:virology*; D015368:Human T-lymphotropic virus 1 / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D007564:Japan / Q000453:epidemiology; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000453:epidemiology* / Q000821:virology*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D011533:Proviruses / Q000235:genetics*; D019562:Viral Load / Q000235:genetics*; D055815:Young Adult
D015415:Biomarkers; D004279:DNA, Viral