Okinawa Prefecture, located in the subtropics, is an area of endemic adult T-cell leukemia-lymphoma (ATL) in Japan. We retrospectively analyzed 659 patients with aggressive ATL in seven institutions in Okinawa between 2002 and 2011. The median patient age was 68 years. More patients were aged ≥90 years (2.6 %), in this study, than in a nationwide survey (<1 %). The median survival time (MST) of the entire cohort was 6.5 months. Of the 217 patients who had a clinical status similar to that stated in the eligibility criteria of JCOG9801 (a randomized phase III study comparing VCAP-AMP-VECP with CHOP-14), 147 who received the CHOP regimen had a poorer MST than those in the CHOP-14 arm of JCOG9801 (8 vs 11 months). The prevalence of strongyloidiasis in the ATL patients was much higher (12.4 %) than in the historical cohort who visited the University of the Ryukyus Hospital (3.4 %). Furthermore, strongyloidiasis may be associated with ATL-related deaths. These findings suggest that, compared with other areas in Japan, in Okinawa, the proportion of patients aged ≥90 years with clinical features of aggressive ATL is higher, outcomes are poorer, and the disease is associated with a higher prevalence of strongyloidiasis.
Keywords: Adult T-cell leukemia–lymphoma; Okinawa; Retrospective analysis; Strongyloidiasis; Subtropics.