Background: The objective of this study was to compare the response rates, ability to mobilize autologous hematopoietic (peripheral blood) stem cells (PBSCs), and progression-free survival (PFS) after second-line chemotherapy with either gemcitabine, dexamethasone, and cisplatin (GDP) or carmustine, etoposide, cytarabine, and melphalan (mini-BEAM) followed by high-dose therapy and hematopoietic stem cell transplantation (ASCT) for patients with recurrent or refractory Hodgkin lymphoma.
Methods: The outcomes of 68 consecutive patients who were referred for salvage therapy (34 patients received mini-BEAM, and 34 patients received GDP) were compared retrospectively. Patients received mini-BEAM as inpatient treatment every 3-4 weeks, whereas GDP was administered on an outpatient basis every 3 weeks. Responding patients proceeded to stem cell mobilization, followed by high dose etoposide and melphalan, and ASCT. Patients who had disease bulk at recurrence that measured > 5 cm received involved-field radiation post-ASCT.
Results: The response rate to GDP prior to ASCT (complete responses, unconfirmed complete responses, and partial responses) was 62% (95% confidence interval [95% CI], 45-78%) compared with 68% (95% CI, 52-83%) for mini-BEAM (P = 0.61). After mobilizing chemotherapy, the proportion of patients for whom the target PBSC number of > or = 5 x 10(6) CD34-positive cells/kg was obtained was 97% after GDP and 57% after MB (P = 0.0003). More patients completed collection with a single apheresis procedure after GDP than after mini-BEAM (73% vs. 36%; P = 0.004), and fewer patients in the GDP group required bone marrow harvesting to proceed to ASCT. After a median follow-up of 1.8 years after ASCT, PFS was significantly better for patients who received GDP compared with patients who received mini-BEAM (74% vs. 35% at 1.5 yrs, respectively; P = 0.005). Overall survival at 1.5 years was 91% after GDP and 82% after mini-BEAM (P = 0.23).
Conclusions: Although this was a retrospective analysis, response to GDP and early PFS after ASCT compared favorably with mini-BEAM salvage chemotherapy. Based on these data, the authors believe that a Phase III trial comparing GDP with mini-BEAM or other platinum-containing regimens is warranted.