Introduction: The purpose of this analysis was to investigate if early sequential high-dose therapy with autologous stem cell transplantation (ASCT) can improve the poor prognosis of patients with disseminated mantle cell lymphoma (MCL).
Patients and methods: A joint analysis of two parallel single center studies was performed. Both were characterized by a sequential high-dose therapy consisting of an intensive chemotherapy ('HAM' or 'Dexa-BEAM') for mobilization of peripheral blood stem cells and induction of minimal disease followed by a total body irradiation-containing myeloablative regimen and ASCT. Forty-six patients with reference panel-confirmed stage III/IV MCL were included. Thirty-four patients were accrued to the protocol immediately after diagnosis ('upfront ASCT' group). These 34 patients received a standard first-line regimen prior to mobilization. The remaining 12 patients were put on the protocol later during the course of their disease ('delayed ASCT' group).
Results: All patients were in remission after mobilization chemotherapy and proceeded to ASCT; there were no exclusions due to poor response, poor mobilization, or patient refusal. With a follow-up of 24 (2-73) months post transplant, the event-free and overall survival probabilities at 2 years were 77 and 100% for the upfront ASCT group compared to 30% (P=0.0007) and 54% (P=0.0016) for the delayed ASCT group. Event-free and overall survival tended to be longer in the upfront ASCT group than in the delayed ASCT group also if calculated from initial diagnosis (76 and 93% vs 42 and 63%, respectively, at 4 years after diagnosis; median follow-up 35 months), although this was not statistically significant. Besides timing of ASCT, only spleen size was identified as an independent predictor of survival by univariate and multivariate analysis.
Conclusion: ASCT is not curative but may improve the prognosis of patients with MCL if performed as part of an intensive first-line treatment strategy. In contrast, the benefits of this approach for salvaging individuals with relapsed disease appear to be limited.