Human T-cell leukemia virus type I Tax genotype analysis in Okinawa, the southernmost and remotest islands of Japan: Different distributions compared with mainland Japan and the potential value for the prognosis of aggressive adult T-cell leukemia/lymphoma

• Published in: Leukemia research 2017-10, Vol.61, p.18-24
• Main Authors: Sakihama, Shugo, Saito, Mineki, Kuba-Miyara, Megumi, Tomoyose, Takeaki, Taira, Naoya, Miyagi, Takashi, Hayashi, Masaki, Kinjo, Shigeko, Nakachi, Sawako, Tedokon, Iori, Nishi, Yukiko, Tamaki, Keita, Morichika, Kazuho, Uchihara, Jun-nosuke, Morishima, Satoko, Karube, Ken-nosuke, Tanaka, Yuetsu, Masuzaki, Hiroaki, Fukushima, Takuya
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Aggressive ATL; Antineoplastic Combined Chemotherapy Protocols - therapeutic use; Female; Gene Products, tax - genetics; Genotype; HTLV-1; HTLV-I Infections - drug therapy; HTLV-I Infections - mortality; HTLV-I Infections - pathology; Human T-lymphotropic virus 1 - genetics; Humans; Japan; Kaplan-Meier Estimate; Leukemia-Lymphoma, Adult T-Cell - mortality; Leukemia-Lymphoma, Adult T-Cell - pathology; Leukemia-Lymphoma, Adult T-Cell - virology; Male; Middle Aged; Okinawa; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Prognosis; Prognostic factor; tax Genotype
• ISSN: 0145-2126; 1873-5835
• DOI: 10.1016/j.leukres.2017.08.006

•The HTLV-1 genotype distributions in Okinawa differs from that in mainland Japan.•The prognosis of aggressive ATL patients with taxA is poorer than those with taxB.•HTLV-1 Tax genotype has potential value as a prognostic factor for aggressive ATL. Okinawa, comprising remote islands off the mainland of Japan, is an endemic area of human T-cell leukemia virus type I (HTLV-1), the causative virus of adult T-cell leukemia-lymphoma (ATL) and HTLV-1-associated myelopathy (HAM). We investigated the tax genotype of HTLV-1 among 29 HTLV-1 carriers, 74 ATL patients, and 33 HAM patients in Okinawa. The genotype distribution—60 (44%) taxA cases and 76 (56%) taxB cases—differed from that of a previous report from Kagoshima Prefecture in mainland Japan (taxA, 10%; taxB, 90%). A comparison of the clinical outcomes of 45 patients (taxA, 14; taxB, 31) with aggressive ATL revealed that the overall response and 1-year overall survival rates for taxA (50% and 35%, respectively) were lower than those for taxB (71% and 49%, respectively). In a multivariate analysis of two prognostic indices for aggressive ATL, Japan Clinical Oncology Group-Prognostic Index and Prognostic Index for acute and lymphoma ATL, with respect to age, performance status, corrected calcium, soluble interleukin-2 receptor, and tax genotype, the estimated hazard ratio of taxA compared with taxB was 2.68 (95% confidence interval, 0.87–8.25; P=0.086). Our results suggest that the tax genotype has clinical value as a prognostic factor for aggressive ATL.