Durability of remission after ABMT for NHL: the importance of the 2-year evaluation point.

Few series describing the results of autologous bone marrow transplantation (ABMT) for the treatment of non-Hodgkin's lymphoma report mature follow-up. We retrospectively reviewed 110 adults with NHL treated with ABMT from 1988 to 1993. Overall survival and relapse-free survival were 50% and 35%, respectively. Estimated median relapse-free survival was 16 months. There was no statistically significant difference in relapse-free or overall survival by low, intermediate, and high-grade histologies, as defined by the International Working Formulation. The most powerful negative prognostic variable was an elevated LDH at the time of transplant (relapse-free survival 17% vs 42% for those with a normal LDH). Forty-seven patients were in complete remission 2 years after transplant. Extended follow-up revealed that 100% of patients with high-grade histologies remained in complete remission, whereas patients with intermediate-grade and low-grade histologies remained at risk of relapse with longer follow-up. Of 22 patients with diffuse large cell lymphoma (LCL) or immunoblastic (IBL) histologies, eight of eight with IBL remain in continued remission, while four of 14 with LCL relapsed 24-48 months after ABMT. We conclude that patients with high-grade histologic subtypes of NHL who are in complete remission 2 years after ABMT are likely to be cured. However, patients with intermediate and low-grade histologic subtypes are at continued risk of relapse and require appropriate clinical surveillance for at least 48 months after ABMT.