Nordic MCL2 trial update: six-year follow-up after intensive immunochemotherapy for untreated mantle cell lymphoma followed by BEAM or BEAC plus autologous stem-cell support: still very long survival but late relapses do occur

Mantle cell lymphoma (MCL) is a heterogenic non-Hodgkin lymphoma entity, with a median survival of about 5 years. In 2008 we reported the early based on the median observation time of 4 years results of the Nordic Lymphoma Group MCL2 study of frontline intensive induction immunochemotherapy and autologous stem cell transplantation (ASCT), with more than 60% event-free survival at 5 years, and no subsequent relapses reported. Here we present an update after a median observation time of 6.5 years. The overall results are still excellent, with median overall survival and response duration longer than 10 years, and a median event-free survival of 7.4 years. However, six patients have now progressed later than 5 years after end of treatment. The international MCL Prognostic Index (MIPI) and Ki-67-expression were the only independent prognostic factors. Subdivided by the MIPI-Biological Index (MIPI + Ki-67, MIPI-B), more than 70% of patients with low-intermediate MIPI-B were alive at 10 years, but only 23% of the patients with high MIPI-B. These results, although highly encouraging regarding the majority of the patients, underline the need of a risk-adapted treatment strategy for MCL. The study was registered at as ISRCTN 87866680