Rituximab is highly effective in eradicating detectable lymphoma cells from the peripheral blood and bone marrow of patients with follicular NHL and can render most patientsPCR-negative. Several studies at ASH evaluated the ability of this antibody to provide effective in vivo purging, permitting the harvesting of large numbers of PCR-negative stem cells for autologous BMT (Gianni et al, abstract #481; Buckstein et al, abstract #2672). Engraftment has been successful in the few patients transplanted to date (Flinn et al, abstract #2673). Obviously, longer follow-up of larger numbers of patients is needed to better evaluate the long-term impact of this approach.
Tsai et al (abstract #1713) made the interesting and somewhat surprising observation of a high response rate with rituximab in patients with intermediate-grade NHL who progressed after high-dose chemotherapy with autologous stem-cell transplantation. The fact that a patient attained a complete remission, together with the five partial remissions observed in seven patients, has stimulated interest in larger studies to confirm the efficacy of this antibody in such a poor-risk patient group.