Inferior outcomes of stage III T lymphoblastic lymphoma relative to stage IV lymphoma and T-acute lymphoblastic leukemia: Long-term comparison of outcomes in the JACLS NHL T-98 and ALL T-97 protocols

T cell lymphoblastic lymphoma (T-LBL) accounts for 30% of all childhood non-Hodgkin's lymphomas (NHL) in Japan. Twenty-nine patients with T-LBL in stages III and IV were eligible for and enrolled in the JACLS NHL-T98 trial (1998-2002), and 72 patients with T-ALL were enrolled in the JACLS ALL-T97 trial (1997-2001). The 10-year overall survival (OS) (61.1 ± 11.5%) and the 10-year event-free survival (EFS) (44.4 ± 11.7%) of stage III LBL were lower than those of other diseases, and the OS and EFS were nearly the same when comparing stage IV LBL and ALL (OS: stage IV LBL, 80.0 ± 12.7% vs. ALL, 80.2 ± 4.9%; EFS: stage IV, LBL 70.0 ± 14.5% vs. ALL, 70.7 ± 5.5%). Outcomes were worse for stage III LBL than for stage IV LBL or T-ALL. Given that the treatment results of T-ALL and LBL stage IV did not differ when compared with previous reports, LBL stage III in Japanese children may differ from LBL stage III in children in other countries.