Long-term survival after autologous bone marrow transplantation for follicular lymphoma in first remission

The role of autologous stem cell transplantation (ASCT) in the treatment of follicular lymphoma is still being defined in the era of antibody therapy. Here we report the long-term 12-year clinical outcomes of patients treated with autologous bone marrow transplantation (ABMT) for follicular non-Hodgkin's lymphoma (NHL) in first remission. Between 1988 and 1993, advanced-stage follicular NHL patients in need of initial therapy were enrolled in 2 consecutive prospective treatment trials of either standard-dose CHOP induction (83 patients) or high-dose CHOP plus granulocyte-colony stimulating factor (G-CSF) (20 patients). Patients who achieved an adequate remission with induction therapy underwent conditioning with cyclophosphamide and total body irradiation (TBI) followed by ABMT in first remission using bone marrow (BM) purged in vitro with anti-B cell monoclonal antibodies and rabbit complement (96 patients). At 12-year follow-up, 61% of the patients are alive and 43% remain in continuing complete remission. The only predictors of decreased progression-free survival proved to be histologic BM involvement at time of harvest (hazard ratio [HR] 2.27, 95% confidence interval [CI] 1.3-3.9, P<.004) and PCR detectable disease in the BM product after purging (HR 4.18, 95% CI 1.99-8.8, P=.0002). No significant predictors of overall survival were identified. These results at 12-year follow-up suggest that a subset of follicular lymphoma patients can experience prolonged survival with ABMT in first remission.

Follicular Lymphoma International Prognostic Index

Although numerous treatment approaches are proposed for patients with follicular lymphoma, criteria to help in choosing a treatment for a given patient and for comparing trial results are lacking. Several retrospective studies have analyzed prognostic factors, but their conclusions rely on limited numbers of patients treated during long periods, and their results are discordant. The Follicular Lymphoma International Prognostic Index was designed from the data recorded over 8 years of nearly 5000 patients registered worldwide. Five factors are used (age, Ann Arbor stage, number of nodal sites, serum lactate dehydrogenase level, and hemoglobin level) to build a three-category index. This index, together with new biologic markers such as gene profiling and proteomics, could help provide an optimal treatment option for patients with follicular lymphoma.

Current controversies in follicular lymphoma

Follicular lymphoma (FL) is characterized by its responsiveness to initial therapy, a pattern of repeated relapses, and a tendency for histologic progression to a process resembling diffuse, large B-cell lymphoma. Treatment decisions are complicated by the many effective options now available including combinations of conventional chemotherapy and monoclonal antibody, radioimmunotherapy, new targeted agents, and autologous and allogeneic stem cell transplantation. For selected patients, "watch and wait" or involved field irradiation may still be the most appropriate strategy. When therapy is required, a combination of rituximab and conventional chemotherapy results in improved outcomes compared to chemotherapy alone. Radioimmunotherapy alone or in combination with chemotherapy is an attractive strategy for patients with relapsed disease and may prove to be appropriate first line therapy. The role of stem cell transplant in FL requires further investigation. Novel agents with varied mechanisms of action continue to be developed. Enrollment of patients into clinical trials designed to address the many unanswered questions in FL is essential to improving clinical outcomes.