A new schedule of CHOP/rituximab plus granulocyte-macrophage colony-stimulating factor is an effective rescue for patients with aggressive lymphoma failing autologous stem cell transplantation.

From 1999 to 2002, 20 patients with aggressive non-Hodgkin lymphoma, among 28 who failed autologous peripheral blood progenitor cell transplantation, were rescued with cyclophosphamide, hydroxydaunomycin, Oncovin (vincristine), and prednisone (CHOP)/rituximab (RTX) and granulocyte-macrophage colony-stimulating factor (GM-CSF). RTX was administered twice during each course of chemotherapy, before CHOP and after GM-CSF. This cytokine was given to increase the antibody-dependent cell-mediated cytotoxicity and to reduce the leukopenia on the basis of our preliminary data, which suggested that this cytokine can upregulate CD20 expression. The relevant (World Health Organization grade 3-4) toxicity mainly consisted of myelosuppression (neutropenia in 60% of patients). Fifteen patients achieved complete remission (CR) or had a partial response, with an overall response rate of 75% (60% CR and 15% partial response). Six of the 12 patients who achieved CR relapsed: 2 died of progressive disease, 1 died of infectious complications after allogeneic transplantation, and 3 are alive in second CR. Eight patients showed progressive disease: 5 died of progressive disease, 1 of secondary acute leukemia, and 1 of infectious complications after allogeneic transplantation, whereas 1 is alive in second CR. At last follow-up, 10 patients are alive, 6 of whom are in complete continuous remission, with a median follow-up of 31 months (range, 3-51 months). The projected 4-year progression-free survival is 31.4%, and the 4-year overall survival is 50%. This new association (RTX, CHOP, and GM-CSF) was feasible in approximately 70% of patients; the overall toxicity was manageable. The good response rate and the promising outcome observed in this subset of patients could be explained by the possible increased synergy between chemotherapy, RTX, and GM-CSF, which should be explored in further studies.